Single-air-source cold air multi-starting system of liquid rocket engine

Abstract

The embodiment of the utility model provides a single-air-source cold air multi-starting system for a liquid rocket engine, which relates to the field of rocket engine starting systems and comprises a high-pressure air source, a plurality of starting air supply pipeline assemblies connected in parallel and an engine turbine assembly. The high-pressure gas source is connected with the gas inlet ends of the multiple starting gas supply pipeline assemblies connected in parallel. The gas outlet end of the parallel multi-path starting gas supply pipeline assembly is connected with the engine turbine assembly; a corresponding starting gas control valve is arranged in each starting gas supply pipeline assembly in series to control on-off. Through combination of a single high-pressure gas source and a plurality of starting gas supply pipeline assemblies with independent on-off control parallel connection, multiple times of same-flow starting gas supply are achieved, the weight of gas cylinders and other assemblies matched with a rocket is reduced, the gas utilization rate is increased, meanwhile, the passivation difficulty is reduced, it is guaranteed that starting states are basically consistent each time, and the service life of the rocket is prolonged. Starting and climbing of the engine within the optimal working range are achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of rocket engine starting system, especially a liquid rocket engine single gas source cold gas multiple starting system. BACKGROUND

[0002] In the traditional technology, the commonly used starting modes of pump pressure type rocket engine include self starting and forced starting, the engine of self starting is strict to time sequence control precision, the system design is complex, and the working condition of starting process climbs slowly, forced starting includes cold gas (high pressure gas) starting, powder starter and starting box scheme, powder starting has the advantages of simple control, high reliability, high starting acceleration, but is not suitable for multiple starting engine, starting box can realize multiple starting, but compared with other schemes, the starting structure of starting box is more complex, compared with the other two forced starting modes, cold gas starting has the common advantages of powder starting and starting box starting, and the system structure is simple, suitable for the reuse of rocket after recovery, and the whole starting system does not need to be replaced.

[0003] The commonly used cold gas starting scheme in the traditional technology includes multiple gas source multiple starting and single gas source multiple starting, multiple gas source multiple starting is matched with multiple sets of completely same and independent starting gas systems, each set of starting gas system has independent gas source, pipeline, valve, throttling element etc., each time starting uses a set, and they are not affected each other, the scheme of single gas source multiple starting uses a set of gas cylinder, control valve and throttling element.

[0004] In the implementation of the utility model, the applicant finds that there are at least the following problems in the prior art:

[0005] The traditional multiple gas source multiple starting system adopts multiple sets of completely same and independent systems, so that the structure weight is large, and the passivation process after flight is complex, the traditional single gas source multiple starting scheme is only matched with one gas supply pipeline, control and throttling unit, with the change of gas source pressure, the pressure and flow before entering the turbine are inconsistent every time starting, so that the starting state of engine is inconsistent every time. INVENTION CONTENTS

[0006] The utility model embodiment provides a kind of liquid rocket engine single gas source cold gas multiple starting system to solve the problems that the traditional multiple gas source multiple starting system is complex, the passivation process after flight is complex, the pressure and flow before entering the turbine are inconsistent every time starting in the traditional single gas source multiple starting scheme, so that the starting state is inconsistent every time.

[0007] To achieve the above purpose, the utility model embodiment provides a kind of liquid rocket engine single gas source cold gas multiple starting system, comprising: comprising: high pressure gas source, multiple starting gas supply pipeline assembly and engine turbine assembly in parallel;

[0008] The high-pressure gas source is connected to the air inlet end of the parallel multi-path starting gas supply pipeline assembly;

[0009] The air outlet end of the parallel multi-path starting gas supply pipeline assembly is connected to the engine turbine assembly;

[0010] Each starting gas supply pipeline assembly is provided with a corresponding starting gas control valve in series to control the on-off.

[0011] Further, the effective cross-sectional areas of the flow passages of different starting gas supply pipeline assemblies are different.

[0012] Further, a starting gas throttle ring is provided in series on each starting gas supply pipeline assembly, and the throttle hole diameters of the starting gas throttle rings provided on different starting gas supply pipeline assemblies are different.

[0013] Further, the parallel multi-path starting gas supply pipeline assembly is specifically a parallel three-path starting gas supply pipeline assembly.

[0014] Further, the air outlet end of the parallel multi-path starting gas supply pipeline assembly is connected to the engine turbine assembly through a starting gas path one-way valve.

[0015] Further, the high-pressure gas source is also connected to a charging pipeline, and the charging pipeline is provided with a gas cylinder charging one-way valve.

[0016] Further, the charging pipeline, the high-pressure gas source, and the air inlet end of the parallel multi-path starting gas supply pipeline assembly are connected through a tee joint.

[0017] Further, the high-pressure gas source is composed of a single gas cylinder or multiple connected gas cylinders.

[0018] Further, the system further comprises a control unit;

[0019] The control unit is connected to the starting gas control valve on each starting gas supply pipeline assembly.

[0020] Further, the starting gas control valve is provided upstream of the starting gas throttle ring.

[0021] The above technical solution has the following beneficial effects: by combining a single high-pressure gas source and a parallel multi-path starting gas supply pipeline assembly with independent on-off control, a multiple starting system is realized, the weight of the gas cylinders and other components matched with the rocket is reduced, the gas utilization rate is improved, the passivation difficulty is reduced, the starting state is basically consistent each time, the engine is started and climbs in the optimal working range. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0023] Figure 1 is a structure schematic diagram of a liquid rocket engine single gas source cold gas multiple starting system according to an embodiment of the present application;

[0024] Figure 2 is a pressure change schematic diagram of a three-time starting high-pressure gas source according to an embodiment of the present application;

[0025] Figure 3 is a starting gas throttle ring post-pressure schematic diagram of a three-time starting process according to an embodiment of the present application;

[0026] Figure 4 is a gas flow comparison schematic diagram of a three-time starting entering an engine turbine assembly according to an embodiment of the present application.

[0027] The reference signs are as follows: 1, high-pressure gas source; 2, starting gas supply pipeline assembly; 3, engine turbine assembly; 4, starting gas control valve; 5, starting gas throttle ring; 6, starting gas one-way valve; 7, charging pipeline; 8, gas cylinder charging one-way valve. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0029] The applicant finds that the gas cylinder multiple starting scheme in the prior art has the following disadvantages: the rocket dry weight significantly affects the carrying capacity of the rocket, multiple independent starting gas systems are provided, multiple pipeline assemblies and gas cylinders and high-pressure gas are carried, although the design scheme is simple, but the dry weight of the rocket is also increased, and the carrying capacity of the rocket is reduced; meanwhile, multiple starting systems are provided, the number of components is increased, and the system reliability is reduced; after the flight is completed, the remaining propellant in the rocket needs to be passivated, multiple independent starting gas systems are provided, and each gas cylinder has more residual gas, and the passivation control complexity and passivation time are increased.

[0030] The applicant finds that the traditional single-gas-bottle multiple starting scheme has the following disadvantages: in the traditional single-gas-source multiple starting system, after completing a starting, the pressure of the gas bottle for the second starting has been reduced, but the same throttle ring is still used for throttling, so that the pressure and flow rate before entering the turbine in the second starting are greatly reduced compared with the first starting, leading to inconsistent states of the two startings, and this starting mode requires a wider range of adaptation of the inlet conditions for engine starting ignition, and generally cannot perform three or more startings; the applicant believes that in order to realize smooth, fast and consistent starting process state of the engine during multiple startings, the pressure of the starting gas before entering the engine needs to be basically similar.

[0031] As shown in Figure 1 The utility model embodiment provides a liquid rocket engine single gas source cold gas multiple starting system, which comprises: a high-pressure gas source 1, a plurality of parallel starting gas supply pipeline assemblies 2 and an engine turbine assembly 3.

[0032] The high-pressure gas source 1 is connected to the gas inlet end of the plurality of parallel starting gas supply pipeline assemblies 2.

[0033] The gas outlet end of the plurality of parallel starting gas supply pipeline assemblies 2 is connected to the engine turbine assembly 3.

[0034] Each starting gas supply pipeline assembly 2 is provided with a corresponding starting gas control valve (4) in series for controlling the on-off state.

[0035] In some embodiments, during actual use, each time the high-pressure gas in the gas source is consumed, the pressure of the gas source is gradually reduced. In order to achieve the consistent starting state of the engine during multiple starts, and to enable the engine to start in a stable, small-vibration, and smooth cold-heat relay process, the flow rate and pressure of the starting gas entering the engine turbine need to be controlled within an optimal working range that is verified through a test run. In order to achieve this goal, the on-off of the multiple starting gas supply pipeline assemblies 2 needs to be controlled in parallel, and the on-off of each starting gas supply pipeline assembly 2 can be independently controlled through the starting gas control valve 4 on the different starting gas supply pipelines. The combination of different starting gas supply pipeline assemblies 2 can be used to construct an overall pipeline with different effective cross-sectional areas of flow, which is composed of one, two, three, or more starting gas supply pipeline assemblies 2, thereby achieving stable control of the flow rate and pressure of the starting gas entering the engine turbine assembly 3, achieving consistent starting state of the engine, and enabling the engine to start in a stable, small-vibration, and smooth cold-heat relay process. The high-pressure gas source 1 is a single gas source, and after multiple starts, the remaining amount of starting gas in the high-pressure gas source 1 is less than that in the multiple-gas-source multiple-start or single-gas-source single-start of the conventional technology, which improves the utilization rate of gas and reduces the difficulty of passivation. The single-gas-source high-pressure gas source 1 cooperates with the parallel multiple starting gas supply pipeline assemblies 2, which has a simpler system structure than the multiple-gas-source multiple-start system of the conventional technology, and reduces the weight of the gas cylinder and other components of the rocket.

[0036] The embodiment of the utility model has the following technical effects: through the combination of single gas source, parallel multi-path starting gas supply pipeline assembly with independent on-off control, realize multiple starting system, reduce the weight of gas cylinder and other components matched with rocket, improve gas utilization rate, reduce passivation difficulty, ensure that the starting state is basically consistent each time, realize the starting and climbing of engine in the optimal working range. The embodiment of the utility model can select and set different number of starting gas supply pipeline assemblies 2 according to the actual engine starting times, for example, starting 2 times, can be matched with two starting gas supply pipeline assemblies 2; the volume and pressure of high-pressure gas source 1 can be determined according to task requirements and specific model engine starting state; starting gas can select multiple inert gases, such as nitrogen and helium. Specifically, in terms of reducing weight, for example, in some embodiments of the utility model, one 100L high-pressure gas cylinder (high-pressure gas source) is matched, the weight of the gas cylinder is 60kg, the weight of high-pressure gas is 29kg (35MPa weight is 33kg), compared with the traditional three independent gas sources (each 100L / 30MPa), the weight of the gas source is reduced by 174kg, in addition, there is the weight of the pipeline assembly; in terms of improving gas utilization rate and reducing passivation difficulty, for example, in some embodiments of the utility model, the pressure of single gas source (100L / 35MPa) is 21MPa after three times starting; in the traditional technology, multiple independent starting gas systems, each gas source (100L / 30MPa), the remaining pressure is 25MPa after starting, the traditional technology needs to passivate more remaining medium, and three roads need to be opened to exhaust all the gas of the gas source. In terms of flow rate and pressure stability before entering the engine turbine, in some embodiments of the utility model, the starting gas flow rate and pressure before entering the engine turbine are guaranteed within 5% deviation range in three times starting.

[0037] Further, the effective cross-sectional area of the flow of different starting gas supply pipeline assemblies 2 is different.

[0038] In some embodiments, the effective cross-sectional area of the flow of starting gas supply pipeline assembly 2 refers to the minimum cross section of the pipeline in starting gas supply pipeline assembly 2, for example, if starting gas supply pipeline 2 has a throttle ring, the effective cross-sectional area of the flow of starting gas supply pipeline 2 usually refers to the cross-sectional area of the throttle ring. Each starting gas supply pipeline 2 provides different effective cross-sectional area of the flow, which can be more finely adjusted to achieve the flow rate and pressure of the engine after combination.

[0039] The embodiments of the present invention have the following technical effects: by combining a single gas source with parallel multi-path starting gas supply pipeline components that have independent on / off control and different effective cross-sections for flow, a multi-start system is realized, reducing the weight of the rocket's gas cylinders and other components, improving gas utilization, reducing passivation difficulty, ensuring that the starting state is basically consistent each time, and realizing the engine's starting and climbing within the optimal operating range.

[0040] Furthermore, each starting gas supply pipeline assembly 2 is equipped with a starting gas throttle ring 5 connected in series, and the throttle ring orifice diameter of the starting gas throttle ring 5 on different starting gas supply pipeline assemblies 2 is different.

[0041] In some embodiments, the starter air control valve 4 is used to isolate the upstream high-pressure air source 1 and the downstream engine, and precisely control the timing of starter air entering and shutting off the engine; the starter air throttle coil 5 is used to control the flow rate of the driving air entering the engine. Each starter air supply pipeline assembly is equipped with a starter air control valve 4 and a starter air throttle coil 5 connected in series. The starter air control valve 4 on different starter air supply pipeline assemblies can independently control the on / off state of each starter air supply pipeline assembly 2. The throttle coil 5 on different starter air supply pipeline assemblies has a different orifice diameter, thus various combinations of the on / off states of the starter air control valve 4 on each starter air supply pipeline assembly 2 can form multiple different effective cross sections, thereby keeping the flow rate and pressure of the starter air entering the engine turbine assembly 3 stable and consistent during different starts. Preferably, by calculating and testing the system using the control of the starter air control valve closing sequence and the throttle coil orifice diameter, the system can achieve three engine starts.

[0042] like Figure 1 As shown, the core of this utility model embodiment lies in the three parallel starting air supply lines (starting air supply pipeline assembly) between the engine (engine turbine assembly 3) and the gas cylinder (equivalent to high-pressure gas source 1). Each line consists of a starting air control valve 4 and a starting air throttle coil 5. The model and specifications of the starting air control valves 4 for the three lines are the same, but the orifice diameter of the throttle coil 5 for each line is different. After passing through the starting air throttle coil 5, the high-pressure gas is in a supercritical state, and the flow velocity reaches the speed of sound. According to the calculation of the gas flow rate through the throttle coil in the "Practical Fluid Resistance Handbook" regarding the outflow of compressible gases, the flow rate formula is as follows:

[0043] Qm=(D 2 *π / 4)*P i *Tm (1)

[0044]

[0045] Among them, P iP is the inlet pressure, i.e. the pressure of the gas cylinder minus the pressure drop of the upstream pipeline and the starting gas control valve 4, D is the aperture of the starting gas throttle 5, and k, R, T are the adiabatic index, the gas constant, and the gas temperature, respectively.

[0046] In actual use, the starting gas control valve 4 is selected to be opened according to the pressure of the high-pressure gas source 1 before starting; and the starting gas throttle 5 with a suitable aperture D is calculated and selected according to the gas source pressure P i and verified through ground cold-blowing tests and ground multi-engine hot tests, and is used in the later launch of the rocket. Through tests, when the initial boost pressure of the high-pressure gas source 1 is 35 MPa (mega pascal), Figure 2 For the purpose of simulating the three starting processes of the engine, the gas source pressure gradually decreases after the three starting processes are completed, and the pressure before starting is 35 MPa, 30 MPa, and 25 MPa, respectively. The actual test deviation is within ±1 MPa. From the simulation results Figure 3 It is found that, by adjusting the on-off combination of the parallel multi-path starting gas supply pipeline assembly 2, different combinations of starting gas throttles 5 are formed, the overall pipeline with different effective cross-sectional areas of flow is formed, the pressure after the three starting throttles is basically the same under different gas source pressures, Figure 4 By aligning the time of opening the starting gas control valve to zero, it is found that the flow rate of each starting path is basically the same, so the pressure and flow rate of the starting gas entering the engine turbine are basically the same, and the three starting states of the engine are also basically the same.

[0047] Further, the parallel multi-path starting gas supply pipeline assembly 2 is specifically a parallel three-path starting gas supply pipeline assembly.

[0048] In some embodiments, by mutual combination of the three-path starting gas supply pipeline assembly, a plurality of overall pipelines with different effective cross-sectional areas of flow can be obtained. Thus, the change of the gas source pressure in the continuous multiple starting processes of the engine can be more flexibly adapted.

[0049] Further, the gas outlet end of the parallel multi-path starting gas supply pipeline assembly 2 is connected with the engine turbine assembly 3 through a starting gas one-way valve 6.

[0050] In some embodiments, the starting gas one-way valve 6 is arranged in the starting gas path, and the purpose is to prevent the high-temperature (>1000K, Kelvin) combustion gas in the engine from flowing back to damage the upstream valve or the gas cylinder after the engine is started.

[0051] Further, the high-pressure gas source 1 is further connected with a charging pipeline 7, and a gas cylinder charging one-way valve 8 is arranged on the charging pipeline 7.

[0052] In some embodiments, one end of the inflation pipeline 7 is connected to the high-pressure gas source 1, and the other end of the inflation pipeline 7 is connected to the inflation port of the high-pressure gas source 1; the gas cylinder inflation one-way valve 8 prevents gas from leaking from the upstream inflation port after the high-pressure gas source 1 is pressurized.

[0053] Further, the inflation pipeline 7, the high-pressure gas source 1, and the intake end of the parallel multi-path starting gas supply pipeline assembly 2 are connected by a tee joint.

[0054] Further, the high-pressure gas source 1 is composed of a single gas cylinder or multiple connected gas cylinders.

[0055] In some embodiments, the use of a single gas cylinder or multiple connected gas cylinders in the high-pressure gas source 1 can be determined according to the total volume of the gas source and the internal space structure arrangement of the rocket body required by the task profile.

[0056] Further, the system further comprises a control unit; the control unit is connected to the starting gas control valve 4 on each starting gas supply pipeline assembly 2.

[0057] In some embodiments, the control timing of the starting gas control valve 4 is designed according to the starting gas pressure of the high-pressure gas source 1 and the required flow rate and pressure of the engine turbine assembly 3, and each starting gas control valve 4 is controlled by the control unit according to the control timing.

[0058] Further, the starting gas control valve 4 is arranged upstream of the starting gas throttle ring 5.

[0059] The embodiments of the present application have the following technical effects: the combination of a single gas source and a parallel multi-path starting gas supply pipeline assembly with independent on-off control realizes a multiple starting system, reduces the weight of the gas cylinders and other components of the rocket, improves the utilization rate of gas, reduces the difficulty of passivation, ensures that each starting state is basically consistent, realizes the starting and climbing of the engine in the optimal working range; further, the combination of a single gas source and a parallel multi-path starting gas supply pipeline assembly with independent on-off control and different effective cross-sections of flow realizes more accurate control of flow rate and pressure; further, the starting gas one-way valve 6 is arranged in the starting gas path to prevent the high-temperature (> 1000K, Kelvin) gas in the engine from flowing back and damaging the upstream valve or the gas cylinder after the engine is started; further, the use of a single gas cylinder or multiple interconnected gas cylinders facilitates the rational use of the rocket body space and controls the load distribution of the rocket body.

[0060] It should be understood that the particular order or hierarchy of steps in processes disclosed is an example that can be re-arranged as desired. Certain of the steps can be performed at the same time, or in a different order. The accompanying method claims set forth in the appended claims are to be interpreted in accordance with the

[0061] In the foregoing detailed description, various features are grouped together in single embodiments for the purpose of streamlining the disclosure. This disclosure is not to be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are expressly recited in each claim. Rather, as the claims below reflect, inventive subject matter lies in fewer than all features of the disclosed embodiments. Thus, the following claims are hereby expressly incorporated into this detailed description, with each claim acting as a separate embodiment of the claimed subject matter.

[0062] Thus, the present disclosure is not to be limited to the embodiments shown herein but is to be accorded the most broad scope consistent with the principles and novel features disclosed. For a more complete

[0063] The foregoing description includes example of one or more embodiments. Of course, not all possible combinations of components or methods described herein can be claimed as an embodiment. One of ordinary skill in the art can realize additional combinations or sub-combinations of the described embodiments are also within the scope of the disclosure. Thus, the embodiments described herein are intended to cover all such additional combinations and permutations. Additionally, protection is afforded to any incorporated text or description of the terms "comprise", "have", "contain" or "include". Furthermore, any term "or" is intended to mean "non-exclusive or".

[0064] The above detailed description merely describes exemplary embodiments of the application, and is not intended to limit the scope of the application. The description of the exemplary embodiments is intended to be illustrative, and not to limit the scope of the application. Various modifications of the exemplary embodiments as described herein will be apparent to those with ordinary skill in the art, and it is intended to use all such modifications and equivalent structures and functions according to the principles and novel features of the subject matter described or illustrated herein. Therefore, the scope of the application is not intended to be limited to the exemplary embodiments described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A liquid rocket engine single propellant source cold gas multiple start system, characterized by, The system comprises: a high-pressure gas source (1), a plurality of parallel start-up gas supply pipeline assemblies (2) and an engine turbine assembly (3); the high-pressure gas source (1) is connected to the gas inlet end of the plurality of parallel start-up gas supply pipeline assemblies (2); the gas outlet end of the plurality of parallel start-up gas supply pipeline assemblies (2) is connected to the engine turbine assembly (3); a start-up gas control valve (4) is arranged in series in each start-up gas supply pipeline assembly (2) to control the on-off state.

2. The liquid rocket engine single propellant source cold gas multiple start system of claim 1, wherein, The effective cross-sectional areas of the start-up gas supply pipeline assemblies (2) are different.

3. The liquid rocket engine single propellant source cold gas multiple start system of claim 2, wherein, A start-up gas throttle ring (5) is arranged in series in each start-up gas supply pipeline assembly (2), and the throttle ring apertures of the start-up gas throttle rings (5) arranged in different start-up gas supply pipeline assemblies (2) are different.

4. The liquid rocket engine single propellant source cold gas multiple start system of claim 1 or 2, wherein, The plurality of parallel start-up gas supply pipeline assemblies (2) are specifically three parallel start-up gas supply pipeline assemblies.

5. The liquid rocket engine single propellant source cold gas multiple start system of claim 1 wherein, The gas outlet end of the plurality of parallel start-up gas supply pipeline assemblies (2) is connected to the engine turbine assembly (3) through a start-up gas path one-way valve (6).

6. The liquid rocket engine single propellant source cold gas multiple start system of claim 1 wherein, The high-pressure gas source (1) is further connected to a charging pipeline (7), and the charging pipeline (7) is provided with a gas cylinder charging one-way valve (8).

7. The liquid rocket engine single propellant source cold gas multiple start system of claim 6, wherein, The charging pipeline (7), the high-pressure gas source (1) and the gas inlet end of the plurality of parallel start-up gas supply pipeline assemblies (2) are connected through a tee joint.

8. The liquid rocket engine single propellant source cold gas multiple start system of claim 1 wherein, The high-pressure gas source (1) is composed of a single gas cylinder or a plurality of connected gas cylinders.

9. The liquid rocket engine single propellant source cold gas multiple start system of claim 1 wherein, The system further comprises a control unit. The control unit is connected to the start-up gas control valve (4) of each start-up gas supply pipeline assembly (2).

10. The liquid rocket engine single propellant source cold gas multiple start system of claim 3, wherein, The start-up gas control valve (4) is arranged upstream of the start-up gas throttle ring (5).

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