WO2014120526A2

WO2014120526A2 - Enhanced rocket engine fueling systems and methods

Info

Publication number: WO2014120526A2
Application number: PCT/US2014/012488
Authority: WO
Inventors: Andrew Stephen HOWELLS
Original assignee: Howells Andrew Stephen
Priority date: 2013-01-29
Filing date: 2014-01-22
Publication date: 2014-08-07
Also published as: WO2014120526A3

Abstract

Enhanced rocket engine fueling systems (S) and methods (M) involving a pressure-fed rocket engine (180) with at least one or high pressure tank (120) and at least one low pressure tank (110), the at least one low pressure tank (110) accommodating a main propellant (111) and comprising a fuel transfer feature, wherein the at least one low pressure tank (110) and the at least one high pressure tank (120) are in fluid communication by way of the fuel transfer feature, and wherein the high pressure tank (120) is configured for automatic replenishment by the at least one low pressure tank (110) by way of the fuel transfer feature.

Description

ENHANCED ROCKET ENGINE FUELING SYSTEMS AND METHODS

CROSS-REFERENCE TO RELATED APPLICATION! S)

[0001] This document is a PCT Application which claims priority to, and the benefit of, U.S. Provisional Patent Application Serial No. 61/758,259, filed on January 29, 2013, entitled "Low Pressure Low Mass Main Tanks," which is herein incorporated by reference in its entirety for ail purposes.

TECHNICAL FIELD

[0002] The subject matter of the present disclosure technically relates to rocket engine sy stems having combustion engine powered rockets. More specifically, the subject matter of the present disclosure technically relates to fueling systems for forcing propel! ant into combustion chambers.

BACKGROUND

[0003] Combustion powered rocket engines require tremendous power to force (to transfer) propellant into their combustion chambers. Combustion powered rockets are able to produce large amounts of thrust relative to their size, mass, and cost of their engines relative to other types of rockets. In many applications, rockets must accelerate at high rates, often over 1 rn/s², in order to achieve practical efficiency. Lower acceleration rates would drastically increase energy loss due to aerodynamic drag or gravity. For many applications, such as space launch from certain bodies with strong gravity, combustion powered rockets may be used to produce sufficient thrust relative to mass.

[0004] Producing this large amount of thrust also requires tremendous power to force (transfer) propellant into a combustion chamber, because chemical propellants may be limited in the amount of their provided chemical energy relative to their volume, thus, necessitating a certain high minimum volumetric flow rate of the propellant into a combustion chamber. This high flow rate of the propellant into a combustion chamber may experience opposing high pressure of the combustion gas within the combustion chamber. This high opposing pressure may greatly increase the requisite amount of feree and energy to drive the propellant into the combustion chamber,

[0005] In the related art, solid-fueled, pressure-fed liquid-fueled, and pump-fed liquid fueled rockets may experience problems in attempting to provide propellant to a combustion chamber. For example, solid-fueled rockets may not require systems for pumping or forcing propellant into a combustion chamber during operation. Instead, the propellant is loaded into a large fuel chamber, using a majority of the rocket itself, even before operation of the rocket begins. This large fuel chamber may serve as both a combustion chamber and a container for most of the propellant. The combustion reaction may propagate throughout the chamber and avoid the need to feed propellant toward the combustion chamber during operation.

[0006] However, in the related art, the presence of the unburned propellant in the combustion chamber may pose a safety hazard, e.g., if the combustion reaction unpredictably regresses to a rapid self-sustaining uncontrollable increase in the rate of combustion. This condition may cause the rocket casing to rupture and lead to potentially devastating consequences. Also, in a solid-fuel rocket, the entire inner surface of the rocket casing may be exposed to the high pressure of the combustion chamber. This condition may require a strong casing which may be heavy and expensive. In the related art, solid-fueled rockets are unduly heavy relative to their thrust energy output, thereby introducing problems that discourage their use as upper stages for heavy-lift space-launch vehicles. Furthermore, related art solid fueled rockets are limited in what types of propellant they can burn, e.g., to propellants with generally lower energy density than that of liquid fueled rockets. Also, related art solid-fueled rockets experience several problems in flight, such as the inability to engage in dynamically throttling, stopping, and restarting.

[0007] Related art pressure-fed rockets use pressurized gas that is applied to a liquid main propellant in a propellant tank in order to force the liquid propellant into a combustion chamber of a rocket. However, these related art pressure-fed rockets have serious disadvantages. These related art heat-powered rockets require high chamber pressure to achieve high efficiency. Pressure-fed liquid-fueled rockets require their propellant tanks to withstand the same high pressure to which the combustion chamber is exposed, whereby very heavy and expensive tanks are required. As a result, related art pressure-fed rockets are not successfully used for a first stage of a rocket or a first stage booster rocket, but they are limited to use for small upper stages, maneuvering thrusters, and retro rockets, thereby requiring undue dependence on high reliability or a fast throttle response. Related art pressure fed rockets suffer from another serious disadvantage. They require a large mass of pressurization gas, a condition which greatly reduces the payload capacity of such related art rockets. Additionally, the high mass and costs of the related art tanks and high mass of pressurization gas of the related art pump-fed rockets are roughly the same, regardless of attempts at optimizing the related art rockets for high thrust or longer burn time.

[0008] Related art pump-fed rockets have also been used in rocket technology; however, these related art pump-fed rockets present other serious problems, e.g., due to their turbo-pumps which comprise many components, such as turbines, pumps, and dedicated burners for powering. Related art turbo-pumps are exorbitant, e.g., in a range of nearly 40% to 65% of the manufacturing cost of a rocket engine, in addition, the related art turbo -pumps increase the number of components in a rocket engine by nearly a factor of 10 to 100 over that of related art pressure-fed rocket engines. The related art turbo-pumps enormously increase the cost and time required for designing, manufacturing, maintaining, and testing of related art pump- ed rocket engines. Further, the related art turbo-pumps may increase the risk of malfunction and the insurance cost. Although the related art turbo-pumps also increase throttle response time over that of basic related art pump-fed engines, this condition also results in poor efficiency for applications, such as maneuvering thrusters, which require many stops and restarts.

SUMMARY

[0009] The subject matter of the present disclosure is directed to enhanced rocket engine fueling systems and methods for at least one pressure-fed rocket engine, the systems and methods involving at least one high pressure tank comprising a size smaller than that of a related art tank, and at least one low pressure tank comprising a size larger than that of the at least one high pressure tank, the at least one low pressure tank accommodating a fuel, e.g., a main propellant, and comprising a fuel transfer feature. The systems anil methods also involve at least one pressurization tank in fluid communication with the at least one low pressure tank and the at least one high pressure tank. The at least one low pressure tank and the at least one high pressure tank are in fluid communication by way of the fuel transfer feature, and wherein the high pressure tank is configured for automatic replenishment by the at least one low pressure main tank by way of the fuel transfer feature. The fuel transfer feature comprises at least one fuel line and a control system, the control system comprising a controller and at least one valve, wherein the at least one valve is controllable by the controller. The controller effects actuation of the at least one valve; and the controller uses a set of executable instructions, such as would be included in software, stored in a storage medium, such as a non-transitory storage medium. The controller is further adapted to multiplex the functions of the at least one low pressure tank, the at least one high pressure tank, and the at least one pressurization tank by selective actuation of the at least one valve. The controller comprises feature, such as a microprocessor and/or an elec tromechanical control ier.

[0010] Various options are possible for pressurizing the at least one high pressure tank by way of the at least one low pressure tank, and for replenishing the at least one high pressure tank with propellant, in accordance with the present disclosure. A first option is providing the rocket engine fueling system with a plurality of high pressure tanks, e.g., a pair of high pressure tanks configured in a parallel orientation, to fuel a rocket engine, each high pressure tank accommodating at least one type of fuel, such as a propellant liquid (same type or different types, depending on the application), in accordance with an embodiment of the present disclosure. For example, in the multiplexing feature of the present disclosure, one high pressure tank in each pair of high pressure tanks is capable of being replenished while the other high pressure tank in each pair of high pressure tanks is supplying fuel to the rocket engine, wherein each high pressure tank: of the pair of high pressure tanks is adapted for switching function with the other high pressure tank: of the pair of high pressure tanks, whereby the rocket engine is capable of continuous operation. Likewise, each high pressure tank of the plurality of high pressure tanks is adapted for switching function with any other high pressure tank of the plurality of high pressure tanks, e.g., the plurality of high pressure tanks is capable of multiplexing its function, such as fueling the rocket engine, filling, and refilling.

[0011] Further, a second option is employing intermittent operation of at least one high pressure tank arranged in the parallel configuration of an enhanced rocket engine fueling system, in accordance with another embodiment of the present disclosure. Each at least one high pressure tank is adapted to intermittently pressurize a combustion chamber of a rocket engine; and each at least one high pressure tank is adapted for intermittent automatic replenishment, whereby the rocket engine is also capable of continuous operation. This second option allows the enhanced rocket engine fueling system to be useful for upper stages or for maneuvering thrusters. Optionally, two high pressure tanks may be used to respectively accommodate two types of propellant. In addition, a single high pressure tank may be employed to accommodate and intermittently feed a first type of propellant while a second type of propellant is fed via a conventional feed system. By selectively controlling the at least one valve by the controller, fueling the rocket engine is optimized for at least one parameter of fuel economy, lower emissions, performance, and stability.

[0012] Furthermore, a third option for an enhanced rocket engine fueling system is employing a plurality of high pressure tanks in a series configuration, wherein an upstream high pressure tank of the plurality of high pressure tanks is adapted for periodic replenishment by a corresponding low pressure tank, and whereby the upstream high pressure tank is capable of supplying a downstream high pressure tank of the plurality of high pressure tanks, in accordance with an embodiment of the present disclosure. In this embodiment, the downstream high pressure tank is adapted to continuously pressurize a combustion chamber of a rocket engine, whereby the rocket engine is capable of continuous operation.

[0013] Benefits of the systems and methods of the present disclosure include, but are not limited to, providing storage for the majority of the propellant in at least one low pressure tank, wherein exposure of the stored propellant a high pressure in a range of that approximate that of the combustion chamber pressure is prevented. The maximum pressure experienced by the at least one high pressure tank of the present disclosure is much lower than that experienced by related art tanks, the at least one high pressure tank of the present disclosure is considerably lighter in mass and considerably less expensive to manufacture than the related art tanks of typical pressure fed rockets. Another mass reduction is effected by eliminating the mass of the pressurization gas itself from the high pressure tank. Furthermore, the rocket engine fueling systems, in accordance with the present disclosure, eliminate the related art need to compromise pressure in a combustion chamber in order to compensate for the increased mass and increased cost of the related art fuel tanks, in the present systems and methods, the combustion chamber pressure is not compromised, whereby higher efficiency is provided.

[0014] Yet, another benefit of the systems and methods of the present disclosure, over related art pump -fed rockets, includes, but is not limited to, the elimination of the related art turbo-pumps. Eliminating the related art turbo- pumps reduces the cost of designing, manufacturing, testing, and maintaining rocket engines, such as those used in the systems and methods of the present disclosure. A reduction in the number of components of the rocket engines used in the systems and methods of the present disclosure also improves safety and reliability of the present rocket engine fueling systems. Another benefit is that the systems and methods of the present disclosure allow the rocket engines to demonstrate a throttle response that is faster than that of related art rocket engines. The enhanced rocket engine fueling systems of the present disclosure are, thus, also reusable and better handle more challenging propellants, such as highly corrosive propeilatits or suspensions of solid parlicles in liquids, than those of related arl; rocket engine systems.

[0015] An additional benefit of the systems and methods of the present disclosure over related art solid fuel rockets include, but are not limited to, eliminating exposure of the stored propellent to the high pressure of a combustion chamber via storage in the low pressure tank, thereby greatly reducing the mass and cost of the at least one high pressure tank, and being capable of dynamically throttling, stopping, and restarting the engine in flight. Another problem with related art solid-fueled rockets which has also been experienced by as related art pressure-fed liquid- fueled rockets, is that they require major portion of their propellant to be stored in large tanks that are exposed to pressure in a range comparable to that of the combustion chamber. The present systems and methods offer a safety benefit, among other benefits, over related art solid-fueled rockets by storing the major portion of the fuel away from the combustion chamber. Furthermore, the present systems and methods, involving at least one liquid-fueled rocket engine, are adapted to bum propellants that, offer a higher energy density, that are more conveniently available in remote locations, such as alien planets, moons, dwarf planets, comets, or asteroids, and that are safer or otherwise useful over restricted propellants used by related art solid fueled rockets for a variety of applications.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above, and other, aspects, features, and advantages of several embodiments of the present disclosure will be more apparent from the following Detailed Description as presented in conjunction with the following several figures of the Drawing.

[0017] FIG. 1 is a diagram illustrating a cutaway view of an enhanced rocket engine fueling system, in accordance with an embodiment of the present invention

[0018] FIG. 2 is a diagram illustrating a cutaway view of an enhanced rocket engine fueling system, in accordance with an embodiment of the present invention.

[0019] FIG. 3 is a diagram illustrating a cutaway view of an enhanced rocket engine fueling system, in accordance with an embodiment of the present invention.

[0020] FIG. 4 is a diagram illustrating a cutaway view of an enhanced rocket engine fueling system, in accordance with an embodiment of the present invention.

[0021] FIG. 5 is a diagram illustrating a cutaway view of an enhanced rocket engine fueling system, in accordance with an embodiment of the present invention.

[0022] FIG. 6 is a diagram illustrating a cutaway view of an enhanced rocket engine fueling system, in accordance with an embodiment of the present invention. [0023] FIG. 7 is a diagram illustrating a cutaway view of an enhanced rocket engine fueling system, in accordance with an embodiment of the present invention.

[0024] FIG. 8 is a diagram illustrating a cutaway view of an enhanced rocket engine fueling system, in accordance with an embodiment of the present invention.

[0025] FIG. 9 is a diagram illustrating a cutaway view of an enhanced rocket engine fueling system, in accordance with an embodiment of the present invention.

[0026] FIG. 10 is a flowchart illustrating a method of using an enhanced rocket fueling engine system, in accordance with an embodiment of the present disclosure.

[0027] FIG. 11 is a flowchart illustrating the ullage clearing step of the method of using an enhanced rocket fueling engine system, as shown in FIG. 10, in accordance with an embodiment of the present disclosure.

[0028] FIG, 12 is a flowchart the terminating step of the method of using an enhanced rocket fueling engine system, as shown in FIG. 10, in accordance with an embodiment of the present disclosure.

[0029] FIG. 13 is a flowchart illustrating the high pressure tank pressurizing step of the method of using an enhanced rocket fueling engine system, as shown in FIG. 10, in accordance with an embodiment of the present disclosure.

[0030] Corresponding reference characters indicate corresponding components throughout the several figures of the Drawing. Elements in the several figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some elements in the figures may be emphasized relative to other elements for facilitating understanding of the various presently disclosed embodiments. Also, common, but well- understood, elements that are useful or necessary in commercially feasible embodiments are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present disclosure.

DETAILED DESCRIPTION

[0031] The following description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of exemplary embodiments. The scope of the disclosure should be determined with reference to the Claims. Reference throughout this specification to "one embodiment," "an embodiment," or similar language means that a particular feature, structure, or characteristic that is described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of the phrases "in one embodiment," "in an embodiment," and similar language throughout this specification may, but do not necessarily; all refer to the same embodiment.

[0032] Further, the described features, structures, or characteristics of the present disclosure may be combined in any suitable manner in one or more embodiments. In the Detailed Description, numerous specific details are provided for a thorough understanding of embodiments of the disclosure. 'Trial the embodiments of the present disclosure can be practiced, without one or more of the specific details, or with other methods, components, materials, and so forth is contemplated as being encompassed by the present disclosure.

[0033] The subject matter of the present disclosure is generally directed to enhanced rocket engine fueling systems and methods for at least one pressure-fed rocket engine, the systems and methods involving at least one high pressure tank comprising a size smaller than that of a related art tank, and at least one low pressure tank comprising a size larger than that of the at least one high pressure tank, the at least one low pressure tank accommodating a fuel, e.g., a main propellant, and comprising a fuel transfer feature, wherein the at least one low pressure tank and the at least one high pressure tank are in fluid communication by way of the fuel transfer feature, and wherein the high pressure tank is configured for automatic replenishment by the at least one low pressure main tank by way of the fuel transfer feature. The fuel transfer feature comprises at least one fuel line, a controller, and at least one valve, wherein the at least one valve is controllable by the controller, and wherein the controller comprises a set of executable instructions, such as would be included in software, stored in a storage medium, such as a non-transitory storage medium.

[0034] Further, the average mass of the pressurization gas is drastically reduced, since the pressurizatioo gas is discarded, e.g., vented through vent valves as well as exhausted through the engine nozzle with the engine's other exhaust) as the propellent is consumed. In the related art, in a conventional pressure-fed rocket, all of the pressurization gas is needed until all of the propellent is consumed. The mass of the pressurization gas is heated to higher temperature; and the high pressure tanks, even with their smaller size and lower mass, can well withstand the combination of high pressure and high temperature. For intermittent, operation, e.g., as used for maneuvering thrusters, an insulation is disposable around the high pressure tanks to maintain the high temperature; and less insulat ion would be required due to the smaller surface area of the tanks.

[0035] Furthermore, enhanced systems of the present disclosure, comprising the at least one high pressure tank, saves cost in its design, manufacture, and maintenance over the expensive related art turbo-pumps of related art pump-fed rockets. The enhanced systems of the present disclosure also have an improved efficiency over related art pump-fed rockets, for at least the reason that the present systems eliminate any need to limit the rocket engine chamber pressure in order to minimize the cost of the related art turbo-pumps (eliminated in the present systems). Also, the high pressure tanks of the present systems are capable of better handling some types of propellents, otherwise more challenging for related art turbo-pumps, such as cryogenic propellants, highly corrosive propellents, and suspensions of solid particles in liquids.

[0036] By example only, the present system comprises two high pressure tanks for each type of propellant. This embodiment would allow one of the high pressure tanks to be replenished from the corresponding low pressure tank while the other high pressure tank is supplying propellant to the rocket engine. In this embodiment, the rocket engine is capable of providing consistent thrust and eliminates any need to stop the engine in order to replenish a high pressure tank until all of the propellant in the large low pressure tanks is depleted.

[0037] While using only one high pressure tank for each type of propellant is possible, using two high pressure tanks for each type of propellant is preferable for applications requiring continuous thrust for longer intervals. However, an embodiment having a single high pressure tank per type of propellant is also preferred for applications, such as maneuvering thrusters, wherein thrust is required only for brief intervals.

[0038] For rocket engines, two types of propellants may be used, one type of which comprises a reducer component, such as hydrogen, hydrocarbon, and hydrazine, and the other type of which comprises an oxidizer component, such as oxygen, mixed oxides of nitrogen, nitric acid, and/or hydrogen peroxide. However, the subject matter of the present disclosure is not limited to any particular choice of propellant, but encompasses all possible rocket fuels. Although the examples given herein focus on possible and preferred hi -propellant rockets, understood is that the subject matter of the present disclosure also encompasses an improvements to the fuel storage and delivery features for rocket engines; therefore, the subject matter of the present disclosure also applies to rocket engines that employ any number of different types of propellants, such as monopropellents and tri-propellents. Furthermore, the embodiments described herein are capable of fueling the rocket engine by using a default parameter for just one type of propellant at a time; and these embodiments are combinable such that different types of propellants are usable in a rocket engine, wherein different fuel feeding strategies, corresponding to the different propeiiant types, are combinable and may involve using a conventional fuel feeding strategy, an enhanced fuel feeding strategy as disclosed herein, a combination of a conventional fuel feeding strategy and an enhanced fuel feeding strategy, and a combination of enhanced fuel feeding strategies. However, since the benefits of each fueling (fuel feeding) strategy is a function of a particular application, using the same topology of propellants in the present enhanced rocket engine fueling systems for all types of propellants is suggested in the present disclosure, unless the types of propellants used in a rocket engine have drastically different flow rates.

[0039] Contemplated and encompassed by the present disclosure are many combinations and configurations of tanks, engines, and cooling systems, etc., as well as any reconfiguration thereof. For example, a propellent may also be used to cool a different engine than the one which it fuels, or to cool both the same engine and a different engine than the one which it fuels. Another example contemplates two high pressure tanks that draw the same type of fuel from different low pressure tanks, etc.

[0040] While the fueling systems disclosed herei may experience small amounts of pressurization gas being released each time a high pressure tank is vented to allow transfer of propeiiant from the low pressure tank to the high pressure tank, the present systems also provide the benefit dissociating the engine chamber pressure from dictating the mass and cost of fabricating the main propeiiant tank, e.g., the low pressure tank. For at least the foregoing reasons, the present systems are capable of effecting a high combustion chamber pressure in a rocket engine to achieve a high efficiency As such, the present systems may require a higher concentration (slightly more moles) of pressurization gas than a related art pressure-fed rocket. The present high pressure tanks are also better suited to withstand high temperatures than the related art large tanks. As such, the present system also contemplates using a combustion-powered pressurization system. This embodiment is preferred if the present systems are used for replacing the related art pump- fed fueling systems of large rockets, e.g., such as those that are larger than conventional pressure-fed conventional rockets, wherein a benefit includes mass reduction (since the complexity of a combustion-powered pressurization system would be offset) and minimal heat loss effects.

[0041] Referring to FIG. 1 , this diagram illustrates a cutaway view of an enhanced rocket engine fueling system 100, in accordance with an embodiment of the present invention. The system 100 is usable with a pressure-fed rocket engine; and the system 100 comprises at least one high pressure tank, e.g., two small high pressure tanks 120, 130 for accommodating one type of propeiiant, and at least one low pressure tank 110 for accommodating a main propeiiant, wherein the at least one low pressure tank comprises a volume larger than that of the at least one high pressure tank, by example only. An additional tank 114 is included to provide pressurization gas through a valve 115 for one of the large propeiiant tanks, e.g., the low pressure tank 110, for accommodating one type of propeiiant, wherein the propeiiant stored in the low pressure tank comprises the same type as the propeiiant stored in the at least one high pressure tank. Optionally, a secondary storage tank 112 may be employed for accommodating a secondary propeiiant 113, such as liquid oxygen, if the primary propeiiant, e.g., the propeiiant 1 , comprises kerosene.

[0042] Still referring to FIG. i , the system 100 comprises high pressure tanks 120, 130 per type of propeiiant; and the low pressure tank 110 is configured to supply the high pressure tank 130 via a fuel line 116 with an input valve 131, was well as the high pressure tank 120 via a fuel line 116 with an input valve 121. Both tanks 120, 130 accommodate a propeiiant that is a reducer, such as kerosene. The system 100 further comprises a buffer tank 117 disposed at a location along the fuel line 116. The buffer tank 117 facilitates filling of the at least one high pressure tank 120, whereby the mass and size of the at least one high pressure tank 120 are minimized. The buffer tank 117 comprises an accordion or bellow shape for facilitating expansion and contraction thereof; and the buffer tank: 117 further comprises an elastomer material for facilitating expansion and contraction thereof. Alternatively, the buffer tank 117 comprises an ullage space with pressurization gas to prevent a vacuum or pressure drop when the high pressure tank is rapidly drawing from the buffer tank 117. This buffer tank 117 would allow an upstream portion of the fuel line 116 to be manufactured as a narrower, lighter, and less expensive element, while still providing adequate flow rates. For example, operation may begin with the high pressure tanks 120, 130 being empty, a typical operation sequence, according to an embodiment of the present disclosure, follows. Preferably, all of the high pressure tanks, e.g., high pressure tanks 120, 130, would be filled before launch of the rocket. Operation commences by opening a vent valve 123 to ensure that the high pressure tank 120 is relieved (vented) of any residual pressurization gas from any previous operation, testing, or maintenance, if this tank has not been previously pressurized, than this venting step may be skipped. The vent valve 123 may remain open; however, if the system 100 is not in a near-vacuum condition and residua! gas from ambient air remains in the high pressure tank: 120, otherwise excessively opposing the Row of the propeliant into the tank 120, then providing a slightly higher pressure to the low pressure tank 110 by way of the tank 114 via the valve 115 is encompassed by the present disclosure. The input valve 121 is then opened to allow the propeliant 111 to Row from the low pressure tank 110 into the high pressure tank 120. Once high pressure tank 120 is filled, its associated input valve 121 is closed.

[0043] Still referring to FIG. 1 , the vent valve 123 may be closed slightly earlier during operation to prevent fuel from escaping or the vent valve 123 may be closed at approximately the same time that the input valve 121 is closed. A pressurization valve 124 is then opened to allow pressurization gas or fuel to flow from a pressurization fluid tank 140 into the high pressure tank 120. If combustion of the pressurization fluids is needed, this combustion is facilitated by an igniter 151. The propeliant ill is then pressurized and ready to be released through an output valve 122 into a combustion chamber 181 of a rocket engine 180, However, before the output valve 122 is opened, ensuring that an output valve 132 of the other high pressure tank, e.g., the high pressure tank 130, is either closed or ensuring that a nearly matching pressure exists in the high pressure tank 130 is recommended, or else a one-way valve may be included in the system 100 to prevent the propeliant 110 from Rowing into the competing tank, e.g., the high pressure tank 130, instead of flowing into the rocket engine 180. As in a conventional rocket, the propeliant may flow through a nozzle 183, and subsequently tlirough a heat exchanger 184, to cool the rocket engine 180 before entering the combustion chamber 181. The pressurization valve 124 may remain open continuously or may open periodically while the high pressure tank 120 is supplying fuel to the rocket engine 180. The igniter 151 may be activated to ignite pressurization fuel for the high pressure tank 120 multiple times before high pressure tank 120 is depleted. The rocket engine 180 further comprises an output side buffer 190. All valves may be of the solenoid type for the systems and methods of the present disclosure. Optionally, any of the valves of the system 100 comprises at least one of an actuator, a solenoid valve, and a pressure regulator. The actuators for the valves each comprises at least one of a hydraulic actuator, a pneumatic actuator, and an electromechanical actuator. Further, the controller is capable of communicating by way of a remote on-board system via at least one of a fiber optic cable and an electronic wire. However, the rocket vehicle, when on the ground or in a different, space vehicle, preferably communicates, for remote stations, by way of electromagnetic radiation, such as via laser and radio signal sources.

[0044] Still referring to FIG. 1, no later than immediately after the high pressure tank 120 begins supplying the propeliant 111 to combustion chamber 181, the other high pressure tank, e.g., the high pressure tank 130, begins filling. For first usage of the high pressure tank 130, the high pressure tank 130 may be filled while the other tank, e.g., the high pressure tank 120, is also being filled. However, on subsequent cycles, the high pressure tank 130 will not have its pressurization vented or will not stop supplying the engine 180 until after the other tank:, e.g., the high pressure tank 120, is supplying the engine ISO at nearly full pressure. Likewise, the high pressure tank 130 filling should be completed before the high pressure tank 120 completes supplying the engine 180, unless there is a suitable buffer. In either case, the liming of filling completion should generally be sufficient to ensure continuous thrust from the engine 180. When the high pressure tank 120 is done supplying the engine 180, its associated output valve 122 should be closed. If the high pressure tank 120 needs refilling, then opening the vent valve 123 is recommended, even if so opening is optional on the first cycle. The system 100 is usable with a conventional pump-fed rocket engine, a pressure-fed rocket engine, or any rocket engine 180 of the present disclosure, e.g., for any other propellant, if any. Preferably, system 100 is usable for all of the types of propellants in a plurality of rocket types.

[0045] Still referring to PIG. 1, the system IOCS further comprises a control system 170 for controlling actuation of each valve of the system 100 via an associated actuator, wherein the control system 170 and the associateil actuators are powered by a power source (not shown). The control system 170 controls actuation of the valves by way of executable instructions usable from a storage medium, such as a non-transitory storage medium. In FIG. 1, the symbols depicting the valves also incl de their associated actuators. The control system 170 may also control the igniters 150, 15 if igniters are included in the system 100. The control system 170 may also include sensors for verifying the movement of the various fluids. Alternatively, the system 100 further comprises timers (not shown) and optional passive flow regulators (not shown), upon which the control system 170 may rely and with which the control system 170 may be electronically coupled. The system 100 further comprises a fluid damper 190 adapted to buffer the output of the high pressure tanks 120, 130 and to ensure consistent output from the engine 180 by damping the propellant input thereto. The fluid damper 190 is included for at least the reason that fluid damping ensures that an operation cycle of the system IOCS does not interfere with stable operation of the engine 180, in accordance with the present di closure.

[0046] Referring to FIG. 2, this diagram illustrates a cutaway view of an enhanced rocket engine fueling system 200, in accordance with an embodiment of the present invention. The system 200 comprises many of the components corresponding to the system 100, as shown in FIG. 1, and further comprises an optional pressurization gas buffering tank 295 and associated valves 296, 297. The pressurization gas buffering tank 295 is adapted to conserve at least one portion of the pressurization gas from a high pressure tank 220 after the high pressure tank 220 is depleted of the propellant 211 and before the high pressure tank 220 is refilled, thereby eliminating any need to dump excess pressurization gas overboard. The pressurization gas buffering tank 295 is also adapted to at least partially re-pressurize the high pressure tank: 220 with the conserved at least one portion of the pressurization gas after the high pressure tank: 220 has been refilled with the propellant 211. This embodiment is useful for low-thrust applications that have either a long burn time or a plurality of shorter bum segments. For example, this embodiment is useful for a maneuvering thruster, for orbital maintenance, or for a re-boosting thruster. For applications that require a high thrus -to-mass ratio, the mass of the pressurization gas buffering tank 295 may exceed the mass of pressurization gas which it saves, wherein one of the other embodiments of the present disclosure may be more useful.

[0047] Referring to FIG. 3, this diagram illustrates a cutaway view of an enhanced rocket engine fueling system 300, in accordance with an embodiment of the present invention. The system 300 fuels a pressure fed rocket 380 and comprises one high pressure tank 320 and one low pressure tank 310 for one of the two types of propellant. In addition, the system 300 comprises another tank 340 for pressurizing the high pressure tank 320. The system 300 further comprises an additional tank 314 and its associated valve 315 for providing pressurization for the low pressure tank 310. This embodiment differs i that the system 300 has only one high pressure tank 320 per type of propel lant 311. While this embodiment provides greater simplicity and is suitable for maneuvering tbrusters or other intermittent mode applications, this embodiment may not provide the output necessary for the rocket engine 380 to ran continuously; and one of the other embodiments of the present disclosure may be more useful for such application.

[0048] Referring to FIG. 4, this diagram illustrates a cutaway view of an enhanced rocket engine fueling system 400, in accordance with an embodiment of the present invention. The system 400 comprises many of the components corresponding to the system 300, as shown in FIG. 3, and further comprises an optional pressurization gas buffering tank 495, analogous to the corresponding component shown in FIG. 2, and an associated valve 497. Trie pressurization gas buffering tank: 495 is adapted to conserve at least one portion of the pressurization gas from a high pressure tank 420 after the high pressure tank 420 is depleted of the propeliant 411 and before the high pressure tank 420 is refilled, thereby eliminating any need to dump excess pressurization gas overboard. The pressurization gas buffering tank 495 is also adapted to at least partially re-pressurize the high pressure tank 420 with the conserved at least one portion of the pressurization gas after the high pressure tank 420 has been refilled with the propeliant 411. This embodiment is also useful for low-thrust applications that have either a long burn time or a plurality of shorter burn segments. For example, this embodiment is useful for a maneuvering thruster, for orbital maintenance, or for a re -boosting thruster. For applications that require a high thrust-to-mass ratio, the mass of the pressurization gas buffering tank 495 may exceed the mass of pressurization gas which it saves, wherein one of the other embodiments of the present disclosure may be more useful.

[0049] Referring to FIG. 5, this diagram illustrates a cutaway view of an enhanced rocket engine fueling system 500, in accordance with an embodiment of the present invention. The system 500 comprises many of the components corresponding to the system 00, as shown in FIG. 1, and comprises two high pressure tanks 520, 530 configured in a series orientation for one type of propeliant 511 and a low pressure tank 510. The two high pressure tanks 520, 530 are connected by a one-way valve 521. The high pressure tank 520 on the output side of the one way valve 521 is connected to the engine 580 via a valve 522, while the other high pressure tanks 530 is connected, through a one-way valve 531, to the large low pressure tank 510.

[0050] Still referring to FIG. 5, only the upstream high pressure tank 530 has a vent valve 533 and high pressure pressurization tank 540 with its corresponding valve 534. The downstream high pressure tank 520 has a pressurization gas, wherein the pressurization gas does not require regular replenishment as it does not require venting. Therefore, the pressurization gas can be applied one time to the high pressure tank: 520, e.g., at the beginning of operation through the same valve 521 through which the propeliant 511 enters tank 520.

[0051] Still referring to FIG. 5, a benefit of the system 500 is t at a separate output side buffer is not required if the minimum gas volume of the downstream high pressure tank 520 is sufficient, whereby the engine 580 remains capable of providing thrust continuously. This embodiment does not require as many valves as does the system 100, as shown in FIG. 1. The system 500 comprises high pressure tanks 520, 530, each having a volume higher than those of the system 100, since the downstream high pressure tank 520 must include capacity sufficient for both the propeliant 511 and enough pressurization gas to properly regulate the output pressure. Alternatively, the downstream high pressure tank 520 requires its own dynamic pressurization system (not shown), optionally including an associated vent valve (not shown). The upstream high pressure tank 530 must include capacity sufficient to compensate for the absence of a second tank being filled while the upstream high pressure tank 530 is filling the downstream high pressure tank 520. Furthermore, the upstream high pressure tank 530 must withstand much higher pressure than the downstream high pressure tank 520 to ensure an adequate flow rate between the high pressure tanks 520, 530.

[0052] Referring to FIG. 6, this diagram illustrates a cutaway view of an enhanced rocket engine fueling system 600 in accordance with an embodiment of the present invention. The system 600 comprises many of the components corresponding to the system 500, as shown in FIG. 5, and further comprises an optional pressurization gas buffering tank 695 and a high pressure pressurization tank 640 with its corresponding valve 634. The optional pressurization gas buffering tank 695 is adapted to conserve at least one portion of the pressurization gas from a high pressure tank 630 after the high pressure tank 630 is depleted of the propel!ant 611 and before the high pressure tank 630 is refilled, thereby eliminating any need to dump excess pressurization gas overboard. The pressurization gas buffering tank 695 is also adapted to at least partially re-pressurize the high pressure tank 630 with the conserved at least one portion of the pressurization gas after the high pressure tank 630 has been refilled with the propellant 611. This embodiment is also useful for low-thrust applications that have either a long burn time or a plurality of shorter burn segments. For example, this embodiment is useful for a maneuvering ihruster, for orbital maintenance, or for a re-boosting thruster. For applications that require a high thrust-to-mass ratio, the mass of the pressurization gas buffering tank 695 may exceed the mass of pressurization gas which it saves, wherein one of the other embodiments of the present disclosure may be more useful.

[0053] Referring to FIG. 7, this diagram illustrates a cutaway view of an enhanced rocket engine fueling system 700, in accordance with an embodiment of the present invention. The system 700 comprises many of the components corresponding to the system 100, as shown in FIG. I, and further comprises a tank ejection system for ejecting the low pressure main tank 710 when the low pressure main tank 710 is depleted of the propellant 711, hut while the high pressure tanks 720, 730 are still nearly full of the propellant 711 in order to increase the target velocity of the rocket that may be achieved by burning the propellant 711 in the high pressure tanks 720, 730 by decreasing the mass of the system 700 prior to burning this last portion of the propellant 711.

[0054] Still referring to FIG. 7, by decreasing the mass of the rocket system 700, increasing a change in velocity is effected by burning the last propellant. In order to fully exploit this feature of system 700, the rocket engine 780 may be stopped in a manner such that both high pressure tanks 720, 730 are simultaneously nearly fully filled before ejecting the low pressure tank 710 and a final bum occurs (in contrast to normal operating cycles, wherein only one of the high pressure tanks in each pair is tilled at a time). A similar strategy of tilling the high pressure tanks as much as possible and then ejecting the low pressure tank as in the system 700 could aiso be employed with the system 300 or the system 500, respectively comprising a single high pressure tank and a pair of high pressure tanks in series for each type of propellant.

[0055] Still referring to FIG. 7, tank ejection system comprises as ejector 704, wherein the ejector 704 comprises at least one of a gas generator powered ejector, explosive bolts, and explosive springs, etc. Pressurization systems, comprising a pressurization tank 714 and an associated valve 7 5 corresponding to the low pressure tank 710 may be ejected therewith as well. A smaller motor (not shown) may be included in the system 700 for use during the final burn after the low pressure tank 710 has been ejected. Alternatively, if multiple motors (not shown) are disposed in parallel, using fewer motors at this stage earlier in the flight is appropriate to avoid excess acceleration while maintaining the high efficiency associated with high combustion chamber pressure of the engine 780. The fuel line 716 may comprise frangible portions 707, 708, e.g., designated weak points, or mechanisms for severing the fuel line 716 if necessary. Examples are indicated by the frangi ble portion 707, disposed upstream of the fork F in the fuel line 716, and the frangible portion 708, disposed downstream of the fork F.

[0056] Referring to FIG. 8, this diagram illustrates a cutaway view of an enhanced rocket engine fueling system 800, in accordance with an embodiment of the present invention. In the system 800, disposing the fuel and the oxidizer is possible in the same high pressure vessel, such as the high pressure tank 820 with a partition, such as partition 891, between the fuel and the oxidizer, reducing the total surface area of the high pressure tank 720 or 820, and whereby the mass and the cost of the sy stems 700 and 800 are reduced. The partition 891 comprises a thin and a light material, since both propellents (fuel and oxidizer) must be pressurized to approximately the same pressure at the same time. The partition 891 comprises a membrane, the membrane comprising an elastomeric material, such as a synthetic polymer. The high pressure tank 820 could use either the same pressiu'ization system, such as a pressurization tank 840 for both types of propeilatrts. Alternatively, separate pressurization systems could be used for the two types of propel lant. Noted is that, if this embodiment is applied to a configuration with more than two high pressure tanks, these high pressure tanks should be paired such that the pressure between each tank of the paired tanks is approximately balanced.

[0057] Still referring to FIG. 8, the system 800 comprises a topology having a bi-propellant fuel configuration, e.g., comprising a single high pressure tank 820 for each type of propellent 811, 813. The single high pressure tank 820 comprises a partition 891 disposed therein and separating the two types of pro ellants 811, 813. The partition 891 comprises a flexible membrane in this example. For a rocket with at least three types of propellants, the system 800 comprises a high pressure tank 820 having at least one partition 891 therein for separating a plurality of types of propellants, such as the at least three types of propellants. This embodiment is usable for some or all of the types of propellants. Another example of the system 800 using multiple partitioned high pressure tanks 820 would be an adaptation of the system 190, shown in FIG, 1, comprising two high pressure tanks 120 per type ofpropeilant. For example, the high pressure tank 20, containing the reducer component, is eotnbmabie with a first additional tank, containing a first oxidizer component: and a high pressure tank 130, containing the reducer component, could be combined with a second additional tank, containing a second oxidizer component. The partitions 891 disposed in the high pressure tanks 120, 130 facilitate reducing the need for ullage clearing motors (not shown). Similar strategies to those described in the preceding paragraph may be implemented for the low pressure vessels, such as the lo pressure tank 810, as well.

[0058] Still referring to FIG. 8 and referring back to FIGS 1-7, applications that require stopping and restarting engines in flight should be considered. All of the topologies disclosed herein may be operated in ways that involve favoring shutdown of the engines when at least one of the high pressure tanks for each type of propellant required for restart is nearly filled, so as to eliminate or reduce the need for the use of ullage motors. The ability to do this is one of many benefits of the systems and methods of the present disclosure. If some of the pressurization gas exists at the "wrong" end of a tank, such pressurization gas passes through the engine, e.g., the rocket engine 880, more readily, since the high pressure tanks comprises a relatively small size, e.g., approximately 1/5 that of the low pressure tank, and, preferably, approximately 1/50 that of the low pressure tank; and their ullage space is even smaller if they are nearly full, e.g., considerably smaller than the ullage space 818 of the low pressure tank 810. As such, only a harmless small quantity of gas would exit before fuel starvation ends and fuel begins to flow. An alternative strategy, encompassed by the present disclosure, eliminates ullage motors (not shown) by including a mechanism (not shown) which pulls the small high pressure tanks toward the main low pressure tanks to clear the ullage. The pulling mechanism further comprises a damper for decreasing acceleration of the high pressure tanks such that the ullage space remains cleared for a sufficient period of time to start; the main engine. Reducing overall ullage may also minimize the diffusion losses if helium is selected as the pressurization gas.

[0059] Referring to FIG. 9, this diagram illustrates a cutaway view of an enhanced rocket engine fueling system 900, in accordance with an embodiment of the present invention. The system 900 comprises many of the components of the system 100, as shown in FIG. 1, and comprises an optional a high pressurization tank 930 for pressurizing a low pressure tank 910, wherein a fueling strategy, as above described, is implemented. In this embodiment, a high pressure tank 930, having an associated vent valve 933, is also a source of pressurization gas for the low pressure tank 910. The vent valve 933 comprises a three-position valve for both transferring gas from the high pressure tank 930 to the low pressure tank 910 by way of a gas duct 960 and transferring gas from the high pressure tank 930 to the ambient environment through an associated vent 935. Because the gas duct 960 is very long and slender, fluid drag in the gas duct 960 may excessively resist flow from the vent valve 933, thereby slowing the critically fast switching cycle. In recompense, the system 900 further comprises a small buffer space 961 disposed along the gas duct 960, wherei the buffer space 960 facilitates closing the vent valve 933, according to the present disclosure. The low pressure tank 910 has an optional pressurization system comprising a pressurization tank 914 and an associated valve 915. Recycling pressurization gas from the high pressure tank 930 to the low pressure tank 910 results in reducing the size, the mass; and the cost of the system 900 and may also result in eliminating the pressurization system for the low pressure tank 9 0, comprising the pressurization tank 914 and the associated valve 915, entirely.

[0060] Referring back to FIGS. 1-9, noted is that the several figures may not be to scale and may not be proportional. The valves and other components are indicated by symbols which are not intended to indicate a particular recommended type of valve or other respective component to an implementer. Noted is that an intermediate pressure tank: may be introduced between the low pressure and high pressure tanks. A tank 112 is a low pressure tank for accommodating an oxidizer. If the intermediate pressure tank is at higher pressure, it might facilitate faster filling of the high pressure tanks. Such a system could be topologically similar to the systems described above and shown in the various figures, except that the output through valve may be directed to another set of high pressure tanks which are operated and configured in a manner similar to the high pressure tanks in the designs disclosed herein.

[0061] Still referring back to FIGS. 1-9, these embodiments involve venting pressurization gas from the high pressure tanks to the ambient environment when it is no longer needed. However, all of the topologies mentioned above are compatible with being modified to recycle some of the pressurization gas from the small high pressure tanks to pressurize the large low pressure tanks. Since the small high pressure tanks are pressurized to a much higher pressure than the large low pressure tank s, the amount of pressurization gas that they vent is far more tha what the low pressure tanks require. Therefore, only a small portion of the vented gas would need to be reused. Several options exist for routing this gas to the low pressure tanks, without supplying more than the low pressure tanks can handle. One option is to use only one of the high pressure tanks to supply a particular low pressure tank if the embodiment switches between multiple high pressure tanks per low pressure tank, e.g., the system 100, as shown in FIG. i . This configuration eliminates undue routing of plumbing to all of the high pressure tanks. Another option, which may be used in combination with the strategy of using only one high pressure tank of a set of parallel high pressure tanks, is to skip some filling cycles. This filling cycle strategy eliminates excess pressure in the low pressure tanks.

[0062] Still referring back to FIGS, i-9, minimizing the mass of the high pressure tanks is beneficial in the embodiments of the enhanced rocket engine fueling systems of the present disclosure, as these embodiments may require a filling cycle that involves switching between high pressure tanks at very high speeds. Since the pressure of the low pressure tanks is, although drastically lower than the peak pressure of the high pressure tanks, significantly higher than the ambient environment, venting to the low pressure tanks may significantly slow down this filling cycle, thereby requiring larger high pressure tanks. If not all of the tanks in a set of parallel high pressure tanks are used for pressurizing the low pressure tanks, then any which are not used for this recycling strategy may require a larger volume for at least this reason.

[0063] Still referring back to FIGS, i-9, the following techniques for achieving taster venting of the high pressure tanks is considered and encompassed by the present disclosure. One such technique comprises transferring gas from a buffer tank, if present, to the low pressure tanks in the system, instead of directly transferring gas from the high pressure tanks to the low pressure tanks. Another option is to include, in the system, a gas buffer, disposed along the fuel line thai leads from a valve that is used for venting a high pressure tank: to a low pressure tank, to avoid flow restrictions otherwise caused by the small diameter of fuel the line (flow rate being a function of cross- sectional area). Venting first from the high pressure tank to a lower pressure tank is essential; however, before venting is completed, switching the venting from the high pressure tank to ambient is also required. This strategy ensures that the pressure in the "high" pressure tank is lower than the pressure in the "low" pressure tank before the propellant flows into the "high" pressure tank. If a sufficiently small amount of gas is vented on each filling cycle, the pressure difference between the high pressure tank and the fuel line to a low pressure tank that supplies the high pressure tank should be adequate to ensure fast venting.

[0064] Still referring back to FIGS. 1-9, instead of using two or more separate valves, the present systems may use the same valve to control venting a high pressure tank to a plurality of possible destinations. For example, instead of having two separate valves to vent a high pressure tank: to a buffer tank and to the ambient environment, a single three-position valve may be used instead. Likewise, a feedback loop, as described below, e.g., in relation to the flowcharts shown in FIGS. 10- 13, ill ustrates an example of using the same valve, 933, for both venting a high pressure vessel to a low pressure vessel, and venting the high pressure vessel to the ambient environment in the present systems and methods. Valves for venting or buffering pressurization gas, or for feeding gas back to a low pressure tank may be consolidated by combining the vent valves from two different small high pressure tanks into a single valve. Similarly, the input valves, leading from the low pressure tank to the high pressure tanks, may be consolidated into a single three-position valve. Likewise, the output valves, leading from the pressure tank to the high pressure tanks, may be consolidated into a single three -position valve.

[0065] A propellant feed system for a pressure-fed rocket engine comprises: a large volume set of one or more low pressure tanks containing a propel lant; a first small high pressure tank:; a second small high pressure tank; a set of one or more thermally powered rocket engines; a control system; a high pressure pressurization system operatively connected to the first small high pressure tank and the second small high pressure tank, configured to provide high pressure pressurization gas into the first small high pressure tank when an appropriate signal is received from the control system and con figured to provide high pressure pressurization gas into the second stnail high pressure tank when an appropriate signal is received from the control system; and a set of valves and actuators operatively connected to the large volume set of one or more low pressure tanks, the first small high pressure tank, the second small high pressure tank, the set of one or more thermally powered rockets engines, the control system, and the high pressure pressurization system, in accordance with an embodiment of the present disclosure.

[0066] A signal from the control system may cause the actuators to open the valves in such a way that a first set of input paths would open, the first set of input paths comprising a set of one or more paths which, when open, collectively, allow propellant to flow from the large volume set of one or more low pressure tanks to the first high pressure tank with the propellant experiencing low fluid resistance, and when the first set of input paths is approximately closed, the first set of input paths would greatly restrict or prevent the flow of propellant from the large volume set of one or more low pressure tanks to the first high pressure tank. A signal from the control system may cause the actuators to actuate the valves in such a way that the first set of input paths would become approximately closed. A signal from the control system may cause the actuators to open the valves in such a way that a second set of input paths would open, the second set of input paths comprising a set of one or more paths which, when open, collectively allow propellant to flow from the large volume set of one or more low pressure tanks to the second high pressure tank with the propellant experiencing low fluid resistance, and when the second set of input paths is approximately closed, the second set of input paths would greatly restrict or prevent the flow of propellant from the large volume set of one or more low pressure tanks to the second high pressure tank. A signal from the control system may cause the actuators to actuate the valves in such a way that the second set of input paths would become approximately closed. A signal from the control system may cause the actuators to open the valves in such a way that a first set of output paths would open, the first set of output paths comprising a set of one or more paths which when open collectively allow propellant to flow from the first high pressure tank to the set of one or more thermally powered rocket engines with the propellant experiencing low fluid resistance, and when the first set of output paths is approximately ciosed, the first set of output paths would greatly restrict or prevent the flow of fluid into the first high pressure tank from the set of one or more thermally powered rocket engines.

[0067] A signal from the control system may cause the actuators to actuate the valves in such a way that the first set of output paths would become approximately closed. A signal from the control system may cause the actuators to open the valves in such a way that a second set of output paths would open, the second set of output paths comprising a set of one or more paths which when open collectively allow propellant to flow from the second high pressure tank to the set of one or more thermally powered rocket engines with the propellant experiencing low fluid resistance, and when the second set of output paths is approximately closed, the second set of output paths would greatly restrict or prevent the flow of fluid into the second high pressure tank from the set of one or more thermally powered rocket engines. A signal from the control system may cause the actuators to actuate the valves in such a way that the second set of output paths would become approximately closed. A signal from the control system may cause the actuators to open the valves in such a way that a first set of vent paths would open, the first set of vent paths comprising a set of one or more paths which when open collectively allow high pressure pressurization gas to flow from the first high pressure tank to the ambient environment with the high pressure pressurization gas experiencing low fluid resistance, and when the first set of vent paths is approximately ciosed, the first set of vent paths would greatly restrict or prevent the flow of gas from the first high pressure tank to the ambient environment.

[0068] A signal from the control system may cause the actuators to actuate the valves in such a way that the first set of vent paths would become approximately closed. A signal from the control system may cause the actuators to open the valves in such a way that a second set of vent paths would open, the second set of vent paths comprising a set of one or more paths which when open collectively allow high pressure pressurization gas to flow from the second high pressure tank to the ambient environment with the high pressure pressurization gas experiencing low fluid resistance, and when the second set of vent paths is approximately closed, the second set of vent paths would greatly restrict or prevent the flow of gas from the large volume set of one or more low pressure tanks to the second high pressure tank. A signal from the control system may cause the actuators to actuate the valves in such a way that the second set of vent paths would become approximately closed. [0069] The set of one or more thermally powered rocket engines includes a heating chamber, wherein a large portion of the thermal energy used to accelerate the exhaust of the set of one or more thermally powered rocket engines is applied to the working fluid of the set of one or more thermally powered rocket engines. The control system is configured to control the actuators such that in a sequence, the first small high pressure tank will be vented of any gas that may give it interior pressure well above the interior pressure of any of the tanks in the large volume set of one or more low pressure tanks, then it is filled with propellant from the large volume set of one or more low pressure tanks, then it is pressurized by high pressure pressurizaiion gas from the high pressure pressurizaiion system, then the first small high pressure tank provides propellant to a heating chamber of a rocket engine, while the second small high pressure tank is vented of any gas that may give it interior pressure well above the interior pressure of any of the tanks in the large volume set of one or more low pressure tanks, then it is filled with propellant, then it is pressurized by high pressure pressurizaiion gas from the high pressure pressurizaiion system, the second small high pressure tank provides propellant to a heating chamber of a rocket engine, this sequence repeating in a cycle.

[0070] The propellant feed system further comprises a buffer tank. A signal from the control system may cause the actuators to open the valves in such a way that a first set of buffer paths would open, the first set of buffer paths comprising a set of one or more paths which when open collectively allow high pressure pressurizaiion gas to flow between the first high pressure tank and the buffer tank with the high pressure pressurization gas experiencing low fluid resistance, and when the first set of buffer paths is approximately closed, the first set of buffer paths would greatly restrict or prevent the flow of gas between the first high pressure tank and the buffer tank. A signal from the control system may cause the actuators to actuate the valves in such a way that the first set of buffer paths would become approximately closed. A signal from the control system may cause the actuators to open the valves in such a way that a second set of buffer paths would open, the second set of buffer paths comprising a set of one or more paths which when open collectively allow high pressure pressurization gas to flow between the second high pressure tank and the buffer tank with the high pressure pressurization gas experiencing low fluid resistance, and when the second set of buffer paths is approximately closed, the second set of buffer paths would greatly restrict or prevent the flow of gas between the second high pressure tank and the buffer tank. A signal from the control system may cause the actuators to actuate the valves in such a way that the second set of buffer paths would become approximately closed. The control system is configured to open the first set of buffer paths at approximately the same time or shortly after the first set of output paths closes during a cycle, then on the same cycle, close the first set of buffer paths when pressure has nearly equalized between the buffer tank and the first small high pressure tank and before or at approximately the same time as the first set of vent paths opening, then on the same or a subsequent cycle, open the first set of buffer paths again shortly after the first set of input paths has closed or at approximately the same time, but before the first set of output paths has opened, then on the same cycle, close the first set of buffer paths when pressure has nearly equalized between the buffer tank and the first small high pressure tank, but before or at approximately the same time as the first set of output paths opening, and open the second set of buffer paths at approximately the same time or shortly after the second set of output valves closes during a cycle, then on the same cycle, close the second set of buffer paths when pressure has nearly equalized between the buffer tank and the second small high pressure tank and before or at approximately the same time as the second set of vent paths opening, then on the same or a subsequent cycle, open the second set of buffer paths again shortly after the second set of input paths has closed or at approximately the same time, but before the second set of output paths has opened, then on the same cycle, close the second set of buffer paths when pressure has nearly equalized between the buffer tank and the second small high pressure tank, but before or at approximately the same time as the second set of output, paths opening, with this sequence repeating in cycles.

[0071] The propellant feed system further comprises a tank ejection system, the tank ejection system comprising a designed weak point joint on a fuel line supplying the first small high pressure tank propeliant from the large volume set of at least one low pressure tank capable of self-weakening upon receiving a control signal from the control system; an ejector configured to remove from a rocket of which the ejector is a part, a low pressure tank which is a member of the large volume set of at least one low pressure tank; and a low pressure propellant sensor configured to send a signal to the control system when the large volume set of the at least one low pressure tank is nearly depleted, wherein the control system is configured to respond to a signal from the low pressure propellant sensor by ensuring that both the first high pressure tank: and the second high pressure tank are fi lled nearly to capacity, then, while the high pressure tanks are in this state, activate the ejector to eject the low pressure tank:,

[0072] The total volume of the first high pressure tank: anil the second high pressure tank is in a range between 0.002% and f0% of the total volume of the large volume set of one or more low pressure tanks. The first high pressure tank and the second high pressure tank are capable of withstanding an average pressure difference between interior pressure and exterior pressure of at least 15 times greater than the largest tank in the large volume set of one or more low pressure tanks. The first high pressure tank and the second high pressure tank are capable of withstanding interior pressure relative to exterior pressure at least 10 times greater than the largest tank in the large volume set of one or more low pressure tanks. The high pressure pressurization system comprises: a pressurization fuel capable of burning when in combination with the propellant; and an igniter capable of igniting the pressurization fuel and propellant in at least one of the two high pressure tanks when activated by the control system. A rocket engine is capable o being supplied with propellant from the first high pressure tank by opening the first set of output paths. I'he rocket engine is also capable of being supplied with propellant from the second set of output paths when it is open.

[0073] A signal from the control system may cause the actuators to open the valves i such a way that a set of feedback paths would open, the set of feedback paths comprising a set of one or more paths which when open collectively allow high pressure pressurization gas to flow from one or more of the first high pressure tank or the second high pressure tank to the large volume set of lo pressure tanks with the high pressure pressurization gas experiencing low fluid resistance, and when the set of feedback paths is approximately closed, the set of feedback paths would greatly restrict or prevent the flow of pressurization gas from the small high pressure tank to the large volume set of one or more low pressure tanks. A signal from the control system may cause the actuators to actuate the valves in such a way that the set of feedback paths would become approximately closed. The actuators which control the valves which can open or close the set of feedback paths controlled by the control system in such a way that when the set of feedback paths is open, the set of feedback paths is able to deliver pressurization gas from one or more of the first high pressure tank, the second high pressure tank, or a buffer tank which is operative! y connected to a buffer valve such that when the buffer valve is opened, the buffer tank can receive pressurization gas from either the first high pressure tank or the second high pressure tank, the set of feedback paths able to deliver this pressurization gas to ullage space in the large volume set of one or more low pressure tank.

[0074] A propellant feed system for a pressure-fed rocket comprises: a large volume set of one or more low pressure tanks containing a propeliant; a first small high pressure tank; a second small high pressure tank; a vent valve connected to the first small high pressure tank configured to release high pressure pressurization gas from the first small high pressure tank when opened; a vent valve actuator configured to control the vent valve; an input valve connected to the first small high pressure Sank: configured to permit propeilant to flow from the large vohsme set of one or more low pressure tanks to the first small high pressure tank when opened; art input valve actuator configured to control the input valve; a one way valve connected to the first small high pressure tank and the second small high pressure tank configured to permit propeilant to flow from the first small high pressure tank to the second small high pressure tank when opened; a high pressure pressurization system connected to the first small high pressure tank configured to provide high pressure pressurization gas into the first small high pressure tank when activated; an output valve connected to the second small high pressure tank configured to permit propeilant to flow from the second small high pressure tank to a combustion chamber of a rocket engine when opened; an output valve actuator configured to control the output valve; and a control system, configured to control the actuators. The con!rol system is configured to control the actuators such that in a sequence, the first small high pressure tank would be vented of any gas that may give it interior pressure well above the interior pressure of any of the tanks in the large volume set of one or more low pressure tanks, then it is pressurized by high pressure pressurization gas from the first high pressure pressurization system, then the first small high pressure tank provides propeilant to the second small high pressure pressurization system, then the second small high pressure tank will provide propeilant to a combustion chamber of a rocket engine, this sequence repeating in a cycle.

[0075] The propeilant feed system further comprises: a buffer tank; a buffer valve configured to permit gas to flow between the first small high pressure tank and the buffer tank when opened; and a buffer valve actuator configured to control the buffer valve and be controlled by the control system. The control system is configured to open the buffer valve at approximately the same time as the one way valve closes on each cycle, then close the buffer valve when pressure has nearly equalized between the buffer tank and the first small high pressure tank and before the vent valve has opened, then open the buffer valve again at approximately the same time or shortly after the input valve has closed, but before the output valve has opened with this sequence occurring for each cycle.

[0076] A propeilant feed system for a pressure- fed rocket engine comprises: a large volume set of one or more large low pressure tanks containing a propeilant; a small high pressure tank; a vent valve connected to the small high pressure tank configured to release high pressure pressurization gas from the small high pressure tank when opened; a vent valve actuator configured to control the vent valve; an input valve connected to the small high pressure tank configured to permit propeilant to flow from the large volume set of one or more low pressure tanks to the small high pressure tank when opened; an input valve actuator configured to control the input valve; a high pressure pressurization system connected to the small high pressure tank configured to provide high pressure pressurization gas into the small high pressure tank when activated; an output valve connected to the small high pressure tank: configured to permit propeilant to flow from the small high pressure tank to a combustion chamber of a rocket engine when opened; an output valve actuator configured to control the output valve; and a con!rol system, configured to control the actuators. The control system is configured to control the actuators such that in a sequence, when operated the smail high pressure tank would be vented through the vent valve of any gas that may give it interior pressure well above the interior pressure of any of the tanks in the large volume set of one or more low pressure tanks, then it would be filled with propeilant from the large volume set of one or more low pressure tanks through the input valve, then it would be pressurized by high pressure pressurization gas from the high pressure pressurization system, the small high pressure tank would provide propeilant through the output valve to a combustion chamber of a rocket engine, this sequence repeating in a cycle.

[0077] The propeilant feed system further comprises: a buffer tank; a buffer valve configured to permit gas to flow between the small high pressure tank anil the buffer tank when opened; and buffer valve actuator configured to control the buffer valve and be controlled by the control system. The control system is configured to open the buffer valve at approximately the same time or shortly after the output valve closes on each cycle, then closes the buffer valve when pressure has nearly equalized between the buffer tank and the small high pressure tank and before the vent valve has opened, then open the buffer valve again at approximately the same time or shortly after the vent valve has closed, but before the input valve has opened with this sequence occurring in cycles. The control system may comprise a feature for facilitating manual operation, e.g., by a human operator.

[0078] Optionally, the high pressure pressurization system comprises: a pressurization fuel capable of burning when in combination with the propellent; and an igniter capable of igniting the pressurization fuel and propellant in the high pressure tank when activated by the control system. The propellant feed system further comprises: a tank ejection system comprising: a frangible portion, e.g., a weak point or weak joint, on a fuel line supplying the input valve propellent from the large volume set of one or more low pressure tanks designed to weaken itself upon receiving a control signal from the control system; an ejector configured to remove from a rocket of which the ejector is a part, a tank which is a member of the large volume set of one or more low pressure tanks; and a low pressure propellant sensor configured to send a signal to the control system when the large volume set of one or more low pressure tanks is nearly depleted. The control system is configured to respond to a signal from the lo pressure propellant sensor and activate the designed weak point joint and the ejector to eject a low pressure tank. The total of the volume of the high pressure tank is recommended in a range of approximately 1/500 to approximately 1/10 of the total volume of the large volume set of low pressure tanks. The first high pressure tank and the second high pressure tank are capable of withstanding interior pressure relative to exterior pressure at least 15 times greater than the largest tank in the large volume set of low pressure tanks.

[0079] A propellant feed system for use in a pressure fed rocket engine comprises: a low pressure tank, a plurality of high pressure tanks, a propellant fluid disposed within the system, a pressurization fluid disposed within at least one of the plurality of high, pressure tanks, a plurality of conduits connecting the low pressure tank and the plurality of high, pressure tanks for facilitating flow of propellant fluid from the low pressure tank to the plurality of high pressure tanks, a plurality of valves associated with the plurality of conduits for regulating the flow of the propellant fluid through the conduits, wherein the plurality of valves are configured to be moved between open and closed positions, a plurality of valve actuators for selectively moving at least one of the plurality of valves between the open and closed positions, a control system for selectively activating the piui'ality of valve actuators in response to the amount of the propellant fluid disposed in the piurality of high pressure tanks.

[0080] The control system comprises a power switch for activating the plurality of valve actuators, a power source, a plurality of tank: sensors adapted to sense propellant fluid level data, a predetermined high pressure tank: propellant threshold, a plurality of actuator signals for actuating the valve actuators, a plurality of tank data signals comprising propellant fluid level data from the tanks, a processor adapted to receive the plurality of tank data signal s and compare the propellant fluid level data with the predetermined high pressure tank propellant threshold, a controller for sending the plurality of actuator signals to the plurality of valve actuator sensors, a plurality of valve actuator sensors adapted to receive the plurality of actuator signals from the controller. The controller sends the piui'ality of actuator signals to the plurality of valve actuator sensors based on the comparison between the propellant fluid level data and the predetermined high pressure tank propellant threshold such that, when the amount of propellant fluid disposed in the high pressure tank is less than the high pressure tank propellant threshold, the control system activates at least one valve of the plurality of valves and moves the at least one valve to the open position, and, when the amount of propellant fluid disposed in the high pressure tank is greater than the high pressure tank propellant threshold, the control sysieni activates at least one valve of the plurality of valves and moves the at least one valve to the closed position.

[0081] The plurality of tank data signals comprises: a low pressure lank data signal comprising the propellant fluid level data from the low pressure tank: and a high pressure tank data signal comprising the propellant fluid level data from the plurality of high pressure tanks. The plurality of tank sensors comprises: a low pressure tank sensor for acquiring propellant fluid level data from the low pressure tank; and a plurality of high pressure tank sensors for acquiring propellant fluid level data from the high pressure tanks. The plurality of valves comprises an input valve and an output valve. The system further comprises: a buffer tank for storing the pressurization fluid, a buffer conduit, a buffer valve for regulating the flow of the pressurization gas between the buffer tank and the plurality of high pressure tanks, a buffer valve actuator for moving the buffer valve between open and closed positions. The control sysieni is configured to selectively move the buffer valve into the open position when the plurality of valves are in the closed positions, and into the closed position when the pressure of the buffer tank and the high pressure tanks are equal. The output valve is disposed between the plurality of high pressure tanks and the rocket engine. The output valve is disposed between the pl urality of high pressure tanks and the buffer tank. The output valve comprises a three-position valve. The output valve is disposed within one of the plurality of conduits between the plurality of high pressure tanks and the rocket engine. The plurality of valves are disposed within the plurality of conduits. The plurality of valves comprise switch valves. The system further comprises an igniter for igniting the pressurization fluid and propellant fluid disposed in the plurality of high pressure tanks, wherein the igniter is selectively activated by the controller by sending an ignition signal from the controller to the igniter.

[0082] The system further comprises a tank ejection system, the tank ejection system comprising: a joint disposed on at least one of the plurality of conduits, an ejection actuator for selectively ejecting the low pressure tank from the system, and an ejectio controller for controlling the ejecting of the low pressure tank from the sysieni when the high pressure tanks are full of propellant. The tank sensors are disposed within the tanks. The tank sensors are disposed on the tanks. The processor is selected from the group consisting of analog, digital, electronic, mechanical, and computer processors. The engines are thermally powered.

[0083] Referring to FIG. 10, this flowchart illustrates a method M of fueling a rocket engine by way of an enhanced rocket engine fueling system, such as the systems 100, 200, 300, 400, 500, 600, 700, 800, 900, in accordance with an embodiment of the present disclosure. The method M comprises: providing an initial vector (an initial instruction for a process) to a fueling system, as indicated by block 1001; providing an accelerometer, as indicated by block 1002; determining whether the fueling system is experiencing a microgravity condition by way of the accelerometer, as indicated by block 10(0, and, if so, clearing ullage of a high pressure tank, as indicated by block 1004, and, if not, closing a buffer vafve to the high pressure tank, as indicated by block 1005; determining whether the high pressure tank is full, as indicated by block 1006, and, if not, performing at least one of closing an output valve of the high pressure tank, and indicated by block 1ΘΘ7, and opening a vent val ve of the high pressure tank, as indicated by block 1008, and, if so, simultaneously performing closing an input valve of the high pressure tank, as indicated by block 1009, and closing a vent valve of the high pressure tank, as indicated by block 1010. The method M further comprises determining whether the high pressure tank is then fully pressurized, as indicated by block 1011, and if not, pressurizing the high pressure tank by way of a gas pressurization tank, as indicated by block 1013, and, if so, determining whether a "filling" mutex is locked, as indicated by block 1012. A mutex, in accordance with the present disclosure includes, but is not limited to, a mutual exclusion object, such as a program object that allows multiple program threads to share the same resource, such as file access, but not simultaneously. When a program is started, a mutex is created with a unique name. After this stage, any thread thai needs the resource roust lock the mutex from other threads while it is using the resource. The mutex is set to unlock when the data is no longer needed or the routine is finished.

[0084] Still referring to FIG. 10, the method M further comprises, if the "mutex is locked," pressurizing the high pressure tank by way of gas pressurization, as indicated by block 1013, and, if not, "locking the mutex," as indicated by block 1014; and opening an output valve, as indicated by block 1015; and determining whether the system is experiencing a flameout emergency by way of an infrared (IR) sensor disposed proximate a main flame of the rocket engine, as indicated by block 1016, and if so, using a main engine igniter, as indicated by block 1017, and, if not, determining whether a shutdown command is required by determining a liquid level of the high pressure tank, as indicted by block 1018. The "mutex lock" is used for supplying the engine. Controlling the filling of any given high pressure tank should be mutually exclusive of controlling the filling any other high pressure tank, but this mutual exclusivity is not required when the rocket vehicle is on the ground and would not occur in our current process. If a shutdown command is required, the system is shutdown; and if the shutdown command is not required, the method M further comprises determining whether the high pressure tank is then fully pressurized, as indicated by block 1019, and, if so, then determining whether the high pressure tank is empty, as indicated by block 1020, and, if not, then pressurizing the high pressure tank by way of the gas pressurization tank, as indicated by block 1021. If the high pressure tank is determined to be empty by determining its liquid level, then releasing the filling mutex is performed, as indicated by block 1022. However, if the high pressure tank is determined to be not empty by determining its liquid level, the method M further comprises determining whether the system is experiencing a flameout emergency by way of an infrared (IR) sensor disposed proximate a main flame of the rocket engine, as indicated by block 1023, and, if so, transmitting an error message to a range safety officer (RSO), as indicated by block 1024.

[0085] Still referring to FIG. 10, after releasing the "filling" mutex, as indicated by block 1022, the method M further comprises closing the output valve, as indicated by block 1026, opening a buffer valve, as indicated by block 1027, closing the buffer valve, as indicated by block 1028, and determining whether the low pressure tank is fully pressured, as indicated by block 1029. If the low pressure tank is fully pressurized, then the method M further comprises opening a vent valve, as indicated by block 1030, and opening an input valve of the high pressure tank, as indicated by block 1033, and determining whether the high pressure tank is full by determining its liquid level, as indicated by block 1034, and, if so, performing one of closing the input valve, as indicated by block 1036, and closing the vent valve, as indicated by block 1037, and, determining whether the high pressure tank is empty, as indicated by block 1038. if the high pressure tank is determined to be not empty by determining its liquid level, then the method M further comprises ejecting the low pressure tank, as indicated by block 1039, but if the high pressure thank is determined to be empty, then the operation of the system terminates, as indicated by block 1040. If the low pressure tank is determined to not be empty, as indicated by block, 1035, then the method M further comprises determining whether the high pressure tank is full, as indicated by block 1034, and, if so, then performing one of closing the input valve, as indicated by block 1009, and closing the vent valve, as indicated by block 1010, and then proceeding with subsequent steps shown in FIG. 10. If the low pressure tank is determined to be not fully pressurized, the method M proceeds to opening a feedback valve, as indicated by block 1031, closing the feedback valve, as indicated by block 1032, and opening the vent valve, as indicated by block 1030, and then proceeding with subsequent steps as shown in FIG. 10.

[0086] Alternatively, in accordance with the present disclosure, a method of controlling a propel!ant feed system in a pressure fed rocket engine comprises: providing a propellant feed system for use in a pressure fed rocket engine, the propellant feed system comprising: a low pressure tank; a plurality of high pressure tanks; a propellant fluid disposed within the system; a pressurization fluid disposed within at least one of the plurality of high pressure tanks; a plurality of conduits connecting the low pressure tank and the plurality of high pressure tanks for facilitating flow of propellant fluid from the low pressure tank to the plurality of high pressure tanks; a plurality of valves associated with the plurality of conduits for regulating the flow of the propellant fluid through the conduits, wherein the plurality of valves are configured to be moved between open and ciosed positions; and a plurality of valve actuators for selectively moving at least one of the plurality of valves between the open and closed positions; providing a control system for selectively activating the plurality of valve actuators in response to the amount of the propellant fluid disposed in the plurality of high pressure tanks, the control system comprising: a power switch for activating the plurality of valve actuators; a power source; a plurality of tank sensors adapted to sense propellant fluid level data; a predetermined high pressure tank propellant threshold; a plurality of actuator signals for actuating the valve actuators; a plurality of tank data signals comprising propellant fluid level data from the tanks; a processor adapted to receive the plurality of tank data signals and compare the propellant fluid level data with the predetermined high pressure tank propellant threshold; a controller for sending the plurality of actuator signals to the plurality of valve actuator sensors; and a plurality of valve actuator sensors adapted to receive the plurality of actuator signals from the controller, wherein the controller sends the plurality of actuator signals to the plurality of valve actuator sensors based on the comparison between the propellant fluid level data and the predetermined high pressure tank propellant threshold such that, when the amount of propellant fluid disposed in the high pressure tank is less than the high pressure tank propellant threshold, the control system activates at least one valve of the plurality of valves and moves the at least one valve to the open position, and when the amount of propellant fluid disposed in the high pressure tank is greater than the high pressure tank propellant threshold, the control system activates at least one valve of the plurality of valves and moves the at least one valve to the closed position; removing the pressurization fluid from the at least one of the plurality of high pressure tanks; adding propellant to the at least one of the plurality of high pressure tanks; adding pressurization fluid to the at least one of the plurality of high pressure tanks; adding propellant to a heating chamber of the pressure fed rocket engine; transmitting the plurality of actuator signals from the controller to the plurality of valve actuator sensors; and activating the at least one valve of the plurality of val ves for mo ving the at least one value to the open and closed positions. Transmitting the plurality of signals from the controller to the plurality of valve actuator sensors permits the flow of the propellant from the low pressure tank to the at least one of the plurality of high pressure tanks.

[0087J Referring to FIG. 11, this flowchart illustrates the ullage clearing step, as indicated by block 1004, of the method M, as shown in FIG. 10, in accordance with an embodiment of the present disclosure. The ullage clearing step, as indicated by block 1004, comprises providing an ullage clearing process, as indicated by block 1101; opening the ullage motor throttles, as indicated by block 1.102; operating the ullage motor igniter, as indicated by block 1103; providing a delay, as indicated by block 1104; determining whether a flameout emergency is experienced by way of using an ullage motor flame I sensor, as indicated by block 1105; and, if so, transmitting an error message to the RSO, as indicated by block 1106; and, if not, determining whether accelerating the rocket should be performed by using an accelerometer, as indicated by block 1107. The accelero meter indicates whether the ullage motor is successful in effecting a nominal acceleration sufficient to clear the ullage space for preparing to start the main engine. If acceleration is needed, as indicated by block 1108, then returning to perform closing of the buffer valve, as indicated by block: 1005, as shown in FIG. 10. [0088] Referring to FIG. 12, this flowchart illustrates the terminating step, as indicated by block 1040, of the method M, as shown in FIG. 10, in accordance with an embodiment of the present disclosure. The terminating step, as indicated by block 1040, comprises commencing termination, as indicated by block 1201; transmitting a termination message to the RSO, as indicated by block 1202; and determining whether a residual thrust is experienced by using an accelerometer, as indicated by block 1203. If residual thrust is experienced, then the terminating step returns to determining whether a residual thrust is experienced by using an accelerometer, as indicated by block 1203. If residual thrust is not experienced, then the method the terminating step comprises providing a delay, as indicated by block 1204; separating a stage by way of frangible components, such as explosive bolts, as indicated by block 1205; and halting operation of the system, as indicated by block 1206.

[0089] Referring to FIG. 13, this flowchart illustrates the high pressure tank pressurizing step, as indicated by block 1001, of the method M, as shown in FIG. 10, in accordance with an embodiment of the present disclosure. The high pressure tank pressurizing step, as indicated by block 1001, comprises: providing a high pressure tank pressurization vector, as indicated by block 1301; injecting pressurization fluid into the high pressure tank, as indicated by block 1302; providing a delay, as indicated by block 1303; igniting the pressurization fluid, as indicated by block 1304; and determining whether the high pressure tank is fully pressurized, as indicated by block 1305. If the high pressure tank is fully pressurized, then the high pressure tank pressuring step returns, as indicated by block 1307, to perform the step of determining whether a microgravity condition is experienced, as indicated by block 1003, as shown in FIG. 10. If the high pressure tank is not fully pressurized, then the high pressure tank pressuring step further comprises transmitting an error message to the RSO, as indicated by block 1306.

[0090] Information as herein shown and described in detail is fully capable of attaining the above-described object of the present disclosure, the presently preferred embodiment of the present disclosure, and is, thus, representative of ihe subject matter which is broadly contemplated by the present disclosure. Ihe scope of the present disclosure fully encompasses other embodiments which may become obvious to those skilled in the art, and is to be limited, accordingly, by nothing other than the appended claims, wherein any reference to an element being made in the singular is not intended to mean "one and only one" unless explicitly so stated, but rather "one or more." All structural and functional equivalents to the elements of the above -described preferred embodiment and additional embodiments as regarded by those of ordinary skill in the art are hereby expressly incorporated by reference and are intended to be encompassed by the present claims.

[0091] Moreover, no requirement exists for a system or method to address each and every problem sought to be resolved by the present disclosure, for such to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. However, that various changes and modifications in form, material, work-piece, and fabrication material detail may be made, without departing from the spirit and scope of the present disclosure, as set forth i the appended claims, as may be apparent to those of ordinary skill in the art, are also encompassed by the present disclosure.

INDUSTRIAL APPLICABILITY

[0092] The subject matter of the present disclosure industrially applies to propulsion systems, e.g., combustion powered rockets. More specifically, the subject matter of the present disclosure industrially to systems for fueling a rocket engine, such as by forcing propellent into a combustion chamber of the engine.

Claims

CLAIMS What is claimed:

1. A propellant feed system for a pressure fed rocket engine comprising:

a large volume set of one or more low pressure tanks containing a propellant;

a first small high pressure tank;

a second small high pressure tank;

a set of one or more thermally powered rocket engines;

a control system;

a high pressure pressurizaiion system operatively connected to the first small high pressure tank: and the second small high pressure tank:, configured to provide high pressure pressurizaiion gas into the first small high pressure tank when an appropriate signal is receiveil from the control system and configured to provide high pressure pressurizaiion gas into the second small high pressure tank when an appropriate signal is received from the control system; and

a set of valves and actuators operatively connected to the large volume set of one or more low pressure tanks, the first small high pressure tank, the second small high pressure tank, the set of one or more thermally powered rockets engines, the control system, and the high pressure pressurizaiion system,

wherein:

a signal from the control system may cause the actuators to open the valves in such a way that a first set of input paths would open, the first set of input paths comprising a set of one or more paths which when open collectively allow propellant to flow from the large volunie set of one or tnore low pressure tanks to the first high pressure tank with the propellant experiencing low fluid resistance, and when the first set of input paths is approximately closed, the first set of input paths would greatly restrict or prevent the flow of propellant from the large volume set of one or snore low pressure tanks to the first high pressure tank,

a signal from the control system may cause the actuators to actuate the valves in such a way that the first set of input paths would become approximately closed,

a signal from the control system may cause the actuators to open the valves in such a way that a second set of input paths would open, the second set of input paths comprising a set of one or more path which when open collectively allow propellant to flow from the large volume set of one or more low pressure tanks to the second high pressure tank with the propellant experiencing low fluid resistance, and when the second set of input paths is approximately closed, the second set of input paths would greatly restrict or prevent the flow of propeilant from the large volume set of one or more low pressure tanks to the second high pressure tank,

a signal from the control system may cause the actuators to actuate the valves in such a way that the second set of input paths would become approximately closed,

a signal from the control system may cause the actuators to open the valves in such a way that a first set of output paths would open, the first set of output paths comprising a set of one or more paths which when open collectively allow propellant to flow from the first high pressure tank to the set of one or more thermally powered rocket engines with the propellant experiencing low fluid resistance, and when the first set of output paths is approximately closed, the first set of output paths would greatly restrict or prevent the flow of fluid into the first high pressure tank from the set of one or more thermally powered rocket engines,

a signal from the control system may cause the actuators to actuate the valves in such way that the first set of output paths wouid become approximately closed,

a signal from the control system may cause the actuators to open the valves in such a way that a second set of output paths would open, the second set of output paths comprising a set of one or more paths which when open collectively allow propellant to Row from the second high pressure tank to the set of one or more thermally powered rocket engines with the propellant experiencing low fluid resistance, and when the second set of output paths is approximately closed, the second set of output paths would greatly restrict or prevent the flow of fluid into the second high pressure tank from the set of one or more thermally powered rocket engines,

a signal from the control system may cause the actuators to actuate the valves in such a way that the second set of output paths would become approximately closed,

a signal from the control system may cause the actuators to open the valves in such a way thai a first set of vent paths would open, the first set of vent paths comprising a set of one or more paths which when open collectively allow high pressure pressunzation gas to flow from the first high pressure tank to the ambient environment with the high pressure pressurization gas experiencing low fluid resistance, and when the first set of vent paths is approximately closed, the first set of vent paths would greatly restrict or prevent the (low of gas from the first high pressure tank to the ambient environment,

a signal from the control system may cause the actuators to actuate the valves in such a way that the first set of vent paths would become approximately closed,

a signal from the control system may cause the actuators to open the valves in such a way that a second set of vent paths would open, the second set of vent paths comprising a set of one or more paths which when open collectively allow high pressure pressurization gas to flow from the second high pressure tank to the ambient environment with the high pressure pressurization gas experiencing low fluid resistance, and when the second set of vent paths is approximately closed, the second set of vent paths would greatly restrict or prevent the flow of gas from the large volume set of one or more low pressure tanks to the second high pressure tank, and

a signal from the control system may cause the actuators to actuate the valves in such a way that the second set of vent paths would become approximately closed.

2. The propellant feed system of claim 1,

wherein the set of one or more thermally powered rocket engines includes a heating chamber, wherein a large portion of the thermal energy used to accelerate the exhaust of the set of one or more thermally powered rocket engines is applied to the working fluid of the set of one or more thermally powered rocket engines, and wherein the control system is configured to control the actuators such that in a sequence, the first small high pressure tank will be vented of any gas that may give it interior pressure well above the interior pressure of any of the tanks in the large volume set of one or more low pressure tanks, then it is filled with propellant from the large volume set of one or more low pressure tanks, then it is pressurized by high pressure pressurization gas from the high pressure pressurization system, then the first small high pressure tank provides propellant to a heating chamber of a rocket engine, while the second small high pressure tank is vented of any gas that may give it interior pressure well above the interior pressure of any of the tanks in the large volume set of one or more low pressure tanks, then it is pressurized by high pressure pressurization gas from the high pressure pressurization system, the second small high pressure tank provides propellant to a heating chamber of a rocket engine, this sequence repeating in a cycle.

3, The propellant feed system of claim 2, further comprising a buffer tank, wherein:

a signal from the control system may cause the actuators to open the valves in such a way that a first set of buffer paths would open, the first set of buffer paths comprising a set of one or more paths which when open collectively allow high pressure pressurizalion gas to flow between the first high pressure tank and the buffer tank with the high pressure pressurization gas experiencing low fluid resistance, and when the first set of buffer paths is approximately closed, the first set of buffer paths would greatly restrict or prevent the flow of gas between the first high pressure tank and the buffer tank,

a signal from the control system may cause the actuators to actuate the valves in such a way that the first set of buffer paths would become approximately closed,

a signal from the control system may cause the actuators to open the valves in such a way that a second set of buffer paths would open, the second set of buffer paths comprising a set of one or more paths which when open collectively allow high pressure pressurization gas to flow between the second high pressure tank and the buffer tank with the high pressure pressurization gas experiencing low fluid resistance, and when the second set of buffer paths is approximately closed, the second set of buffer paths would greatly restrict or prevent the flow of gas between the second high pressure tank and the buffer tank,

a signal from the control system may cause the actuators to actuate the valves in such a way that the second set of buffer paths would become approximately closed, and

wherein the control system is configured to open the first set of buffer paths at approximately the same time or shortly after the first set of output paths closes during a cycle, then on the same cycle, close the first set of buffer paths when pressure has nearly equalized between the buffer tank and the first small high pressure tank and before or at approximately the same time as the first set of vent paths opening, then on the same or a subsequent cycle, open the first set of buffer paths again shortly after the first set of input paths has closed or at approximately the same time, but before the first set of output paths has opened, then on the same cycle, close the first set of buffer paths when pressure has nearly equalized between the buffer tank and the first small high pressure tank, but before or at approximately the same time as the first set of output paths opening, and open the second set of buffer paths at approximately the same time or shortly after the second set of output valves closes during a cycle, then on the same cycle, close the second set of buffer paths when pressure has nearly equalized between the buffer tank and the second small high pressure tank and before or at approximately the same time as the second set of vent paths opening, then on the same or a subsequent cycle, open the second set of buffer paths again shortly after the second set of input paths has closed or at approximately the same time, but before the second set of output paths has opened, then on the same cycle, close the second set of buffer paths when pressure has nearly equalized between the buffer tank and the second small high pressure tank, but before or at approximately the same tinie as the second set of output paths opening, with this sequence repeating in cycles.

4. The propellant feed system of claim 2, further comprising a tank e jection system, the tank ejection system comprising:

a designed weak point joint on a fuel line supplying the first small high pressure tank propellant from the large volume set of one or more low pressure tanks designed to weaken itself upon receiving a control signal from the control system;

an ejector configured to remove from a rocket of which the ejector is a part, a low pressure tank which is a member of the large volume set of one or more low pressure tanks; and a low pressure propellant sensor configured to send a signal to the control system when the large volume set of one or more low pressure tanks is nearly depleted,

wherein the control system is configured to respond to a signal from the low pressure propellant sensor by ensuring thai both the first high pressure tank and the second high pressure tank are filled nearly to capacity, then while the high pressure propellant tanks are in this state, activate the ejector to eject the lo pressure tank.

5. The propellant feed system of claim 1, wherein the total of the volume of the first high pressure tank and the second high pressure tank is between 0.002% and 10% the total volume of the large volume set of one or more low pressure tanks.

6. The propellant feed system of claim 2, wherein the totai of the volume of the first high pressure tank and the second high pressure tank is between 0.002% and 10% the total volume of the large volume set of one or more low pressure tanks.

7. The propellant feed system of claim 2, wherein the first high pressure tank and the second high pressure tank are capable of withstanding average pressure difference between interior pressure and exterior pressure at least 15 times greater than the largest tank in the large volume set of one or more low pressure tanks.

8. The propellant feed system of claim 5, wherein the first high pressure tank and the second high pressure tank are capable of withstanding average pressure difference between interior pressure and exterior pressure at least 15 times greater than the largest tank in the large volume set o f low pressure tanks.

9. The propellant feed system of claim 2, wherein the first high pressure tank and the second high pressure tank are capable of withstanding interior pressure relative to exterior pressure at least 10 times greater than the largest tank in the large volume set of one or more low pressure tanks.

10. The propellant feed sy stem of claim 6, wherein the first high pressure tank and the second high pressure tank are capable of withstanding interior pressure relative to exterior pressure at least 10 times greater than the largest tank in the large volume set of one or more low pressure tanks.

11. The propellant feed system of claim 2, wherein the high pressure pressunzation system comprises;

a pressunzation fuel capable of burning when in combination with the propellant; and

an igniter capable of igniting the pressunzation fuel and propellant i at least one of the 2 high pressure tanks when activated by the control system.

12. The propellant feed system of claim 1, wherein a rocket engine configured to be able to be supplied propellant from the first high pressure tank by opening the first set of output paths is also configured to be able to be supplied propellant from the second set of output paths when it is open.

13. The propellant feed system of claim 2, wherein a rocket engine configured to be able to be supplied propellant from the first high pressure tank by opening the first set of output paths is also configured to be able to be supplied propellant from the second set of output paths whe it is open.

14. The propellant feed system of claim 1 , wherein:

a signal from the control system may cause the actuators to open the valves its such a way that a set of feedback paths would open, the set of feedback paths comprising a set of one or more paths which when open collectively allow high pressure press urization gas to flow from one or more of the first high pressure tank or the second high pressure tank to the large volume set of low pressure tanks with the high pressure pressurizatioii gas experiencing low fluid resistance, and when the set of feedback paths is approximately closed, the set of feedback paths would greatly restrict or prevent the flow of pressurization gas from the small high pressure tank to the large volume set of one or more low pressure tanks, and

a signal from the control system may cause the actuators to actuate the valves in such a way that the set of feedback paths would become approximately closed, and

wherein the actuators which control the val ves which can open or close the set of feedback paths controlled by the control system in such a way that when the set of feedback paths is open, the set of feedback paths is able to deliver pressurization gas from one or more of the first high pressure tank, the second high pressure tank, or a buffer tank which is operatively connected to a buffer valve such that when the buffer valve is opened, the buffer tank can receive pressurization gas from either the first high pressure tank or the second high pressure tank, the set of feedback paths able to deliver this pressurization gas to ullage space in the large volume set of one or more low pressure tank.

15. The propellant feed system of claim 2, wherein:

a signal from the control system may cause the actuators to open the valves in such a way that a set; of feedback paths would open, the set of feedback paths comprising a set of one or more paths which when open collectively allow high pressure pressurization gas to flow from one or more of the first high pressure tank or the second high pressure tank to the large volume set of low pressure tanks with the high pressure pressurization gas experiencing low fluid resistance, and when the set of feedback paths is approximately closed, the set of feedback paths would greatly restrict or prevent the flow of pressurization gas from the small high pressure tank to the large volume set of one or more low pressure tanks, and

wherein the actuators which control the valves which can open or close the set of feedback paths controlled by the control system in such a way that whe the set of feedback paths is open, the set of feedback paths is able to deliver pressurization gas from one or more of the first high pressure tank, the second high pressure tank, or a buffer tank which is operatively connected to a buffer valve such that when the buffer valve is opened, the buffer tank ca receive pressurization gas from either the first high pressure tank or the second high pressure tank, the set. of feedback paths able to deliver this pressurization gas to ullage space in the large volume set of one or more low pressure tank.

16. A propellant feed system for a pressure-fed rocket, the system comprising:

a large volume set of one or more low pressure tanks containing a propellant;

a first small high pressure tank; a second smali high pressure tank;

a vent valve connected to the first small high pressure tank configured to release high pressure pressurization gas from the first small high pressure tank whets opened;

a vent valve actuator configured to control the vent valve;

an input valve connected to the first small high pressure tank configured to permit propeilant to flow from the large volume set of one or more low pressure tanks to the first small high pressure tank when opened;

an input valve actuator configured to control the input valve;

a one way valve connected to the first small high pressure tank and the second small high pressure tank configured to permit propeilant to flow from the first small high pressure tank to the second small high pressure tank, when opened;

a high pressure pressurization system connected to the first small high pressure tank configured to provide high pressure pressurization gas into the first small high pressure tank when activated;

an output valve connected to the second small high pressure tank configured to permit propeilant to flow from the second small high pressure tank to a combustion chamber of a rocket engine when opened;

an output valve actuator configured to control the output valve; and

a control system, configured to control the actuators;

wherein the control system is configured to control the actuators such that in a sequence, the first smali high pressure tank would be vented of any gas that may give it interior pressure well above the interior pressure of any of the tanks in the large volume set of one or more low pressure tanks, then it is pressurized by high pressure pressurization gas from the first high pressure pressurization system, then the first small high pressure tank provides propeilant to the second small high pressure pressurization system, then the second small high pressure tank will provide propeilant. to a combustion chamber of a rocket engine, this sequence repeating in a cycle.

17. The propeilant feed system of claim 16, further comprising:

a buffer tank;

a buffer valve configured to permit gas to flow between the first small high pressure tank and the buffer tank when opened; and

a buffer valve actuator configured to control the buffer valve and be controlled by the control system, wherein the control system is configured to open the buffer valve at approximately the same time as the one way valve closes on each cycle, then close the buffer valve when pressure has nearly equalized between the buffer tank and the first small high pressure tank and before the vent, valve has opened, then open the buffer valve again at approximately the same time or shortly after the input valve has closed, hut before the output valve has opened with this sequence occurring for each cycle.

18. A propeilant feed system for a pressure-fed rocket engine, the system comprising:

a large volume set of one or more large low pressure tanks containing a propeilant;

a small high pressure tank;

a vent valve connected to the small high pressure tank configured to release high pressure pressurization gas from the small high pressure tank when opened;

a vent valve actuator configured to control the vent valve;

an input; valve connected to the small high pressure tank configured to permit propeilant; to flow from the large volume set of one or more low pressure tanks to the sniaii high pressure tank when opened; an input valve actuator configured to control the input valve;

a high pressure pressurization system connected to the stnall high pressure tank configured to provide high pressure pressurization gas into the small high pressure tank when activated;

an output valve connected to the small high pressure tank configured to permit propellant to flow from the small high pressure tank to a combustion chamber of a rocket engine when opened;

an output valve actuator configured to control the output valve; and

a control system, configured to control the actuators,

wherein the control system is configured to control the actuators such that in a sequence, when operated the small high pressure tank: would be vented through the vent valve of any gas that may give it interior pressure well above the interior pressure of any of the tanks in the large volume set of one or more low pressure tanks, then it would be filled with propellant from the large volume set of one or more low pressure tanks through the input valve, then it would be pressurized by high pressure pressurization gas from the high pressure pressurization system, the small high pressure tank would provide propellant through the output valve to a combustion chamber of a rocket engine, this sequence repeating in a cycle.

19. The propellant feed system of claim 18, further comprising:

a buffer tank;

a buffer valve configured to permit gas to flow between the small high pressure tank and the buffer tank when opened; and

a buffer valve actuator configured to control the buffer valve and be controlled by the control system, wherein the control system is configured to open the buffer valve at approximately the same time or shortly after the output valve closes on each cycle, then closes the buffer valve when pressure has nearly equalized between the buffer tank and the small high pressure tank and before the vent valve has opened, then open the buffer valve again at approximately the same time or shortly after the vent valve has closed, but before the input valve has opened with this sequence occurring in cycles.

20. The propellant feed system of claim 18, wherein the control system comprises a human operator.

21. The propellant feed system of claim 18, wherein the high pressure pressurization system comprises:

a pressurization fuel capable of burning when in combination with the propellant; and

an igniter capable of igniting the pressurization fuel and propellant in the high pressure tank when activated by the control system.

22. The propellant feed system of claim 18, further comprising:

a tank ejection system comprising:

a designed weak point joint on a fuel line supplying the input valve propellant from the large volume set of one or more low pressure tanks designed to weaken itself upon receiving a control signal from the control system; an ejector configured to remove from a rocket of which the ejector is a part, a tank which is a member of the large volume set of one or more low pressure tanks; and

a low pressure propellant sensor configured to send a signal to the control system when the large volume set of one or more iow pressure tank s is nearly depleted,

wherein the control system is configured to respond to a signal from the low pressure propellan sensor and activate the designed weak point joint and the ejector to eject a low pressure tank.

23. The propellant feed system of claim 18, wherein the total of the volume of the high pressure tank is between one five hundredth and one tenth the total volume of the large volume set of lo pressure tanks.

24. The propellant feed system of claim 18 wherein the first high pressure tank and the second high pressure tank are capable of withstanding interior pressure relative to exterior pressure at least 15 times greater than the largest tank in the large volume set of iow pressure tanks.

25. A propellant feed system for use in a pressure fed rocket engine, the system comprising;

a low pressure tank;

a plurality of high pressure tanks;

a propellant fluid disposed within the system;

a pressurization fluid disposed within at least one of the piui'ality of high pressure tanks;

a plurality of conduits connecting the low pressure tank and the plurality of high pressure tanks for facilitating flow of propellant fluid from the iow pressure tank to the plurality of high pressure tanks;

a plurality of valves associated with the plurality of conduits for regulating the flow of the propellant fluid through the conduits, wherein the plurality of valves are configured to be moved between open and closed positions;

a plurality of valve actuators for selectively moving at least one of the plurality of valves between the open and closed positions; and

a control system for selectively activating the plurality of valve actuators i response to the amount of the propellant fluid disposed in the plurality of high pressure tanks.

26. The system of claim 25, wherein the control sy stem comprises;

a power switch for activating the plurality of valve actuators;

a power source;

a plurality of tank sensors adapted to sense propellant fluid level data;

a predetermined high pressure tank propellant threshold;

a plurality of actuator signals for actuating the valve actuators;

a plurality of tank data signals comprising propellant fiuid level data from the tanks;

a processor adapted to receive the plurality of tank data signals and compare the propellant fluid level data with the predetermined high pressure tank propellant threshold;

a controller for sending the plurality of actuator signals to the plurality of v alve act uator sensors; and a plurality of valve actuator sensors adapted to receive the plurality of actuator signals from the controller, wherein the controller sends the plurality of actuator signals to the piui'ality of valve actuator sensors based on the comparison between the propellant fluid level data and the predetermined high pressure tank propeliant threshold such that,

when the amount of propeiiant fluid disposed in the high pressure tank "is less than the high pressure tank propellani threshold, the control sysieni activates at least one valve of the plurality of vaives and moves the at least one valve to the open position, and

when the amount of propellani fluid disposed in the high pressure tank is greater than the high pressure tank propeliant threshold, the control system activates at least one valve of the plurality of valves and moves the at least one val ve to the closed position.

27. The system of claim 26, wherein the piurality of tank data signals comprises:

a low pressure tank data signal comprising the propeliant fluid level data from the low pressure tank; and a high pressure tank data signal comprising the propeliant fluid level data from the plurality of high pressure tanks.

28. The system of claim 26. wherein the piurality of tank sensors comprises:

a low pressure tank sensor for acquiring propeliant fluid level data from the low pressure tank; and a plurality of high pressure tank sensors for acquiring propeliant fluid level data from the high pressure tanks.

29. The system of claim 25, wherein the piurality of valves comprises an input valve and an output val ve.

30. The system of claim 29, further comprising:

a buffer tank for storing the pressurization fluid;

a buffer conduit;

a buffer valve for regulating the flow of the pressurization gas between the buffer tank and the plurality of high pressure tanks; and

a buffer valve actuator for moving the buffer valve between open and closed positions,

wherein control system is configured to selectively move the buffer valve into the open position when the plurality of val ves are in the closed positions, and into the closed position when the pressure of the buffer tank and the high pressure tanks are equal.

31. The system of claim 29, wherein the output valve is disposed between the plurality of high pressure tanks and the rocket engine.

32. The system of claim 30, wherein the output valve is disposed between the plurality of high pressure tanks and the buffer tank.

33. The system of claim 30, wherein the output valve comprises a three -position val ve.

34. The system of claim 29, wherein the output valve is disposed within one of the plurality of conduits between the plurality of high pressure tanks and the rocket engine.

35. The system of claim 25, wherein the plurality of vaives are disposed within the piurality of conduits.

36. The system of claim 25, wherein the plurality of vaives comprise switch valves.

37. The system of claim 25, further comprising an igniter for igniting the press urization fluid and propellant fluid disposed in the plurality of high pressure tanks, wherein the igniter is selectively activated by the controller by sending an ignition signal from the controller to the igniter.

38. The system of claim 25, further comprising a tank ejection system comprising:

a joint disposed at least one of the plurality of conduits;

an ejection actuator for selectively ejecting the low pressure tank from the system; and

an ejection controller for controlling the ejecting of the low pressure tank from the system when the high pressure tanks are full of propellant.

39. The system of claim 26, wherein the tank sensors are disposed within the tanks.

40. The system of claim 26, wherein the tank sensors are disposed on the tanks.

41. The system of claim 26, wherein the processor is selected from the group consisting of analog, digital, electronic, mechanical, and computer processors.

42. A method of controlling a propellant feed system in a pressure fed rocket engine, the method comprising: providing a propellant feed system for use in a pressure fed rocket engine, the propellant feed system comprising:

a low pressure tank;

a plurality of high pressure tanks;

a propellant fluid disposed within the system;

a pressurization fluid disposed within at least one of the pl urality of high pressure tanks;

a plurality of conduits connecting the low pressure tank and the plurality of high pressure tanks for facilitating flow of propellant fluid from the low pressure tank to the plurality of high pressure tanks;

a plurality of valves associated with the plurality of conduits for regulating the flow of the propellant fluid through the conduits, wherein the plurality of valves are configured to be moved between open and closed positions; and

a plurality of valve actuators for selectively moving at least one of the plurality of valves between the open and closed positions;

providing a control system for selectively activating the plurality of valve actuators in response to the amount of the propellant fluid disposed in the plurality of high pressure tanks, the control system comprising: a power switch for activating the plurality of valve actuators;

a power source;

a plurality of tank sensors adapted to sense propellant fluid level data;

a predetermined high pressure tank propellant threshold;

a plurality of actuator signals for actuating the valve actuators;

a plurality of tank data signals comprising propellant fluid level data from the tanks;

a processor adapted to receive the plurality of tank data signals and compare the propellant fluid level data with the predetermined high pressure tank propeilant threshold;

a controller for sending the plurality of actuator signals to the plurality of valve actuator sensors; and a plurality of valve actuator sensors adapted to receive the plurality of actuator signals from the controller, wherein the controller sends the plurality of actuator signals to the plurality of valve actuator sensors based on the comparison between the propellant fluid level data and the predetermined high pressure tank propellant threshold such that

when the amount of propellant fluid disposed in the high pressure tank is less than the high pressure tank propellant threshold, the control system activates at least one valve of the plurality of valves and moves the at least one valve to the open position, and

when the amount of propeilant fluid disposed in the high pressure tank is greater than the high pressure tank propellant threshold, the control system activates at least one valve of the plurality of valves and moves the at least one valve to the closed position;

removing the pressurization fluid from the at least one of the plurality of high pressure tanks;

adding propellant to the at least one of the plurality of high pressure tanks;

adding pressurization fluid to the at least one of the plurality of high pressure tanks;

adding propellant to a heating chamber of the pressure fed rocket engine;

transmitting the plurality of actuator signals from the controller to the plurality of valve actuator sensors; and

activating the at least one valve of the plurality of valves for moving the at least one value to the open and closed positions.

43. The method of claim 42, wherein transmitting the plurality of signals from the controller to the plurality of valve actuator sensors permits the flow of the propellant from the low pressure tank to the at least one of the plurality of high pressure.

44. The system of claim 25, wherein the engines are thermally powered.

45. An enhanced rocket engine fueling system, the system comprising:

at least one low pressure tank adapted to accommodate a fuel;

at least one high pressure tank adapted to accommodate the fuel and to provide the fuel to a rocket engine; at least one pressurization tank adapted to accommodate a pressurization gas for pressurizing at least one of the at least one low pressure tank and the at lea st one high pressure tank; and

a control system comprising a controller and at least one valve, the controller i operational communication with the at least one valve, and the controller adapted to effect actuation of the at least one val ve, the at least one high pressure tank in fluid communication with the at least one low pressure tank and the at least one pressurization tank, and

the at least one valve associated with at least one of the at least one low pressure tank, the at least one high pressure tank, and the at least one pressurization tank.

46. The system of claim 45,

wherein the at least one high pressure tank comprises a plurality of high pressure tanks, and

wherein the plurality of high pressure tanks is configured in one of a series configuration, a parallel configuration, and a combination of series and parallel configurations.

47. The system of claim 45, wherein the at least one valve comprises at least one of a solenoid valve, a oneway valve, a two-way valve, a three-way valve, a four-way valve, a multi-way valve, an input valve, an output valve, a vent valve, a pneumatic valve, a hydraulic valve, and a rotational motor valve.

48. The system of claim 45,

wherein the fuel comprises a propeUant, and

wherein the propeUant comprises at least one type.

49. The system of claim 48, wherein the at least one type comprises at least one of an oxidizer component and a reducer component.

50. The sy stem of claim 45 ,

wherein the at least one high pressure tank comprises a plurality of high pressure tanks,

wherein the controller is adapted to multiplex the functions of at least one of the at least one low pressure tank, the at least one high pressure tank, and the at least one gas pressmization tank by selective actuation of the at least one valve, and

whereby fueling the rocket engine is improved for at least one parameter of fuel economy, performance, stability, thrust control, faster restart, engine life, manufacturing, and maintenance.

51. The system of claim 45,

wherein the controller is operable by way of a set of executable instructions stored in a non-transitory storage medium for effecting selective actuation of the at least one valve, and

wherein the selective actuation comprises at least one of continuous operation and intermittent operation of at least one selected valve of the at least one valve.

52. The system of claim 45, further comprising at least one pressurization gas buffering tank in fluid communication with the at least one high pressure tank:, the at least one pressurization gas buffering tank adapted to conserve at least one portion of a pressurization gas from the at least one high pressure tank, after depletion of the fuel and before refilling with the fuel, and adapted to at least partially re-pressurize the at least one high pressure tank with the at least one conserved portion of the pressurization gas after refilling with the fuel,

whereby emission of excess pressurization gas is eliminated, and

whereby thrust control is improvable.

53. The system of claim 48, wherein the at least one high pressure tank comprises at least one partition for accommodating the propeUant having a plurality of types.

54. The system of ciaim 45, wherein the rocket engine comprises at least one thermally powered rocket engine.

55. The system of claim 45,

wherein the operational communication between the controller and the at least one valve comprises at least one of a mechanical communication, an electromechanical communication, an optical communication, an electronic communication, a wire communication, a wireless communication, and a remote communication, and

wherein the mechanical communication comprises at least one of a pushrod, a pull rod, a rotating shaft, a direct cable, and a housed cable, and

wherein the optical communication comprises a fiber optical element, anil

wherein the wireless communication comprises an infrared element.

56. The system of claim 45, further comprising at least one fuel line for facilitating fluid communication, wherein the control system further comprises a feedback system in communication with the controller and adapted to sense at least one condition of at least one of the at least one low pressure tank, the at least one high pressure tank, the at least one gas pressurization tank, at least one buffer tank, and the at least one fuel line, the feedback system capable of initiating pressurization to the at least one low pressure tank,

wherein the at least one condition comprises at least one of a flow rate, a pressure, and a temperature, and wherein the controller is further adapted to interactively adjust operation of the at least one valve as a function of the at least one condition sensed by the feedback system.

57. The system of claim 56, wherein the controller is further adapted to interactively adjust operation of the at least one valve by controlling an opening duration and a flow rate.

58. The system of claim 57, further comprising at least one buffer tank disposable along the at least one fuel line, wherein the controller is further adapted to interactively adjust operation of the at least one valve by controlling flow of the fuel in a manner which minimizes at least one condition of drag and turbulence in the at least one fuel line, and wherein the at least one buffer tank is capable of increasing a flow rate of the propellant to the at least one high pressure tank.

59. The system of claim 57, wherein the controller is further adapted to interactively adjust operation of the at least one valve by controlling flow of the pressurization gas in a manner which minimizes at least one condition of incompressible flow from the at least one high pressure tank to the ambient environment, wherein the controller is further adapted to intermittently adjust operation of the at least, one valve by controlling a direction of a pressurization gas flow, whereby steering of a rocket is effected.

60. A method of fabricating an enhanced rocket engine fueling system, the method comprising:

providing at least one low pressure tank adapted to accommodate a fuel;

providing at least one high pressure tank adapted to accommodate the fuel and to provide the fuel to a rocket engine;

providing at least one pressurization tank adapted to accommodate a pressurization gas for pressurizing at least one of the at least one low pressure tank and the at least one high pressure tank; and

providing a control system comprising a controller and at least one valve, the controller in operational communication with the at least one valve, and the controller adapted to effect actuation of the at least one valve, the at least one high pressure tank providing comprising providing the at least one high pressure tank in fluid communication with the at least one low pressure tank and the at least one pressurization tank, and

the control system providing comprising providing the at least one valve associated with at least one of the at least one low pressure tank, the at least one high pressure tank, and the at least one pressurization tank.

61. A method of fueling a rocket engine by way of an enhanced rocket engine fueling system, the method comprising:

providing an enhanced rocket engine fueling system, the fueling system providing comprising:

providing at least one low pressure tank adapted to accommodate a fuel;

providing at least one pressurization tank adapted to accommodate a pressurization gas for pressurizing at least one of the at least one low pressure tank and the at least one high pressure tank; and providing a control system comprising providing a controller and providing at least one valve, the controller providing comprising providing the controller in operational communication with the at least one vaive, and the controller providing comprising providing the controller adapted to effect actuation of the at least one valve,

the at least one high pressure tank providing comprising providing the at least one high pressure tank in fluid communication with the at least one low pressure tank and the at least one pressurization tank, and

the control system providing comprising providing the at least one valve associated with at least one of the at least one low pressure tank, the at least one high pressure tank, and the at least one pressurization tank; and

operating the control system.

62. The method of claim 6 i ,

wherein operating comprises operating the controller by way of executing a set of instructions stored in a non-transitory storage medium for effecting selective actuation of the at least one valve, and

wherein effecting the selective actuation comprises at least one of continuously operating and intermittently operating at least one se lected valve of the at least one valve.