Circulating turbine enhanced combined power system of methane pre-cooling gas generator

Abstract

The invention discloses a methane pre-cooling fuel gas generator circulation turbine enhanced combined power system which comprises a fuel turbine, a heat exchanger, a gas generator, a gas generator, a gas generator, a gas generator, a gas generator, a gas generator and a gas generator, and is characterized in that the heat exchanger is used for providing heat for fuel from a fuel pump and conveying high-temperature fuel gas to the fuel turbine so as to drive the fuel turbine to rotate; the oxidant turbine is used for driving the oxidant turbine to rotate by taking the high-temperature fuel gas output by the heat exchanger and the high-temperature fuel gas flowing out of the fuel turbine as power, so that the oxidant turbine drives the oxidant pump to work; high-temperature fuel gas obtained after the fuel from the fuel pump is heated by the heat exchanger is also used for being converged with high-temperature fuel gas sequentially passing through the fuel turbine and the oxidant turbine and then entering the fuel gas generator; liquid methane is adopted for precooling incoming flow, the total temperature of incoming flow behind an air inlet channel is effectively reduced, the upper limit of the working Mach number of the turbine core machine can be expanded to be larger than Ma3.5, a stamping mode matched with the turbine core machine only needs to consider the working speed range larger than Ma3.5, and the working performance of the turbine core machine can be well released.

Description

Technical Field

[0001] The invention belongs to the field of aerospace propulsion, and in particular relates to a methane precooling gas generator cycle turbine enhancement combined power system. Background Art

[0002] The Air Turbo Rocket (ATR) engine is an air-breathing propulsion system that combines a turbine engine with a rocket engine. The main components of the ATR engine include a compressor, a gas generator, a turbine, a combustion chamber, and a tail nozzle. When working, the high-temperature, fuel-rich gas generated by the gas generator drives the turbine, and the turbine drives the compressor to pressurize the incoming air. The pressurized air is mixed with the fuel-rich gas that passes through the turbine and burns in the combustion chamber, generating high-temperature gas that is accelerated and ejected through the nozzle to generate thrust. The ATR engine has a higher specific impulse than a rocket engine, a higher thrust-to-weight ratio than a turbine engine, and a large thrust adjustment range, with moderate technical difficulty.

[0003] However, with the increase of flight Mach number, the total temperature of the incoming flow continues to rise. On the one hand, the circulation heating amount is gradually reduced, reducing the thrust output of the engine. On the other hand, due to the temperature limitation of the compressor, the actual pressure ratio provided by the compressor continues to decrease. The core engine composed of compressor and rocket turbine contributes very little to the thrust at high Mach number and becomes the dead weight of the engine.

[0004] In this regard, it is possible to consider using precooling technology to cool the incoming flow, reduce the total temperature of the incoming flow, increase the air flow rate at high Mach numbers and increase the pressure ratio, thereby improving the engine's performance and broadening its operating speed range. In the prior art, the indirect precooling engine represented by the Synergistic Air-Breathing Rocket Engine (SABRE) of Reaction Dynamics of the United Kingdom has made great progress and breakthroughs in cycle schemes, key technologies and principle prototype development. Most studies use liquid hydrogen as fuel and precoolant, which has the advantages of good cooling performance and no carbon and coking, but has low operating temperature, is difficult to store for a long time, and is expensive. At the same time, the high temperature and high pressure hydrogen fuel in the pipeline may cause hydrogen embrittlement of the heat exchanger material, and hydrogen leakage in the precooler will bring safety risks. Summary of the invention

[0005] The purpose of the present invention is to provide a methane precooling gas generator cycle turbine enhanced combined power system to solve the problems of low operating temperature, difficulty in long-term storage and high price when liquid hydrogen is used as fuel and precoolant, and the high temperature and high pressure hydrogen fuel in the pipeline may cause hydrogen embrittlement of the heat exchanger material, and hydrogen leakage in the precooler will bring safety risks.

[0006] The present invention adopts the following technical solution: a methane precooling gas generator cycle turbine enhanced combined power system, comprising:

[0007] A fuel turbine is used to drive a fuel pump;

[0008] A heat exchanger is used to provide heat to the fuel from the fuel pump, heat the fuel to form high-temperature fuel gas, and transmit the high-temperature fuel gas to the fuel turbine to drive the fuel turbine to rotate;

[0009] The oxidant turbine is used to drive the oxidant turbine to rotate by using the high-temperature fuel gas output from the heat exchanger and the high-temperature fuel gas flowing out from the fuel turbine as power, so that the oxidant turbine drives the oxidant pump to work;

[0010] The high-temperature fuel gas obtained by the heat exchanger heating the fuel from the fuel pump is also used to merge with the high-temperature fuel gas that passes through the fuel turbine and the oxidant turbine in sequence and then enter the gas generator.

[0011] Furthermore, it also includes:

[0012] A precooler having an air flow path inlet, an air flow path outlet, a fuel flow path inlet, and a fuel flow path outlet;

[0013] Its air flow path inlet is connected to the air intake duct outlet;

[0014] Its air flow path outlet is connected to the compressor inlet;

[0015] Its fuel flow path inlet is connected to the fuel pump outlet;

[0016] Its fuel flow path outlet is connected to the cold source inlet of the heat exchanger;

[0017] The precooler is used to use the low-temperature fuel from the fuel pump to cool the high-temperature incoming air, so that the temperature of the incoming air is reduced and then delivered to the compressor, and then the low-temperature fuel is heated and delivered to the heat exchanger for further heat exchange.

[0018] Furthermore, it also includes:

[0019] A pre-combustion chamber having a fuel inlet, a fuel outlet, and an air inlet;

[0020] Its fuel inlet is connected to the gas outlet of the main turbine;

[0021] Its fuel outlet is connected to the heat source inlet of the heat exchanger;

[0022] Its air inlet is connected to the outlet of the compressor;

[0023] The pre-combustion chamber is used to pre-combust the high-temperature combustion gas from the main turbine with air before transmitting it to the heat exchanger; and to heat the fuel from the fuel pump in the heat exchanger.

[0024] Furthermore, it also includes:

[0025] A combustion chamber having a gas inlet and an air inlet;

[0026] Its gas inlet is connected to the gas outlet of the ATR's main turbine;

[0027] Its air inlet is connected to the heat source outlet of the heat exchanger;

[0028] The combustion chamber is used for complete combustion of the rich fuel gas from the main turbine that has been cooled by the heat exchanger and the air from the compressor.

[0029] The beneficial effects of the present invention are:

[0030] The present invention uses a precooler to keep the compressor inlet air flow temperature constant or change only within an allowed range, thereby improving the working performance of the engine and widening the working speed range of the engine;

[0031] The engine of the present invention uses methane as fuel and precoolant, and liquid oxygen as oxidant. The liquid oxygen / methane propellant combination has the characteristics of abundant resources, non-toxicity and pollution-free, good cooling performance, strong repeatability, etc.

[0032] The present invention adopts liquid methane to pre-cool the incoming flow, effectively reducing the total temperature of the incoming flow in the inlet duct, and can expand the upper limit of the working Mach number of the turbine core engine to above Ma3.5. The ramjet mode matched with it only needs to take into account the working speed range above Ma3.5, and its working performance can be better released; therefore, the combined engine of the present invention can obtain better working performance and a wider working range, and can perform mode conversion at a higher Mach number. At this time, the ramjet engine has better performance and can effectively solve the "thrust gap" problem during mode conversion relay;

[0033] The liquid methane precooled by the present invention can be used as both fuel and precoolant, without the need to carry other inert cooling media; when the engine is working, the liquid methane with high vaporization latent heat is first used as a working medium for driving the fuel turbine and the oxidant turbine after heat exchange through the precooler and the heat exchanger, and then enters the gas generator for subsequent combustion; in the ramjet mode, the methane after the fuel pump is driven directly enters the precombustion chamber and the combustion chamber for combustion, so that the liquid methane carried by the combined engine of the present invention is fully utilized, which is beneficial to reducing the weight of the engine and improving the engine thrust-to-weight ratio;

[0034] From the perspective of cycle thermal efficiency, methane as a precoolant absorbs the heat of the high-temperature incoming flow. This energy is used to drive the fuel turbine and the oxidant turbine and finally enters the gas generator. On the one hand, it eliminates the adverse effects of the incoming flow temperature increase on the engine performance, and on the other hand, it utilizes this part of the incoming flow energy, thereby improving the cycle thermal efficiency.

[0035] The present invention has excellent wide-range acceleration capability. By precooling the incoming flow, a larger compressor pressure ratio can be achieved at a high Mach number, thereby improving engine performance to obtain greater thrust and specific thrust. In terms of cruising capability, a faster acceleration process can be used to enter the cruising speed as quickly as possible, and a longer cruising distance can also be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic diagram of the turbine mode of the present invention;

[0037] Figure 2 It is a schematic diagram of the stamping mode of the present invention.

[0038] Among them: 10. Fuel turbine; 11. Heat exchanger; 12. Oxidant turbine; 13. Fuel pump; 14. Oxidant pump; 15. Precooler; 16. Precombustion chamber; 17. Combustion chamber; 18. Main turbine; 19. Compressor. DETAILED DESCRIPTION

[0039] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. The "direction" in the present invention is based on the position of the present invention in a certain direction. Figure 1 Description of the trend in the state.

[0041] The present invention discloses a methane precooling gas generator cycle turbine enhancement combined power system, such as Figure 1 As shown, it includes: a fuel turbine 10, a heat exchanger 11, and an oxidant turbine 12.

[0042] The fuel turbine 10 is used to drive the fuel pump 13 to work; the heat exchanger 11 is used to provide heat for the fuel from the fuel pump 13, heat the fuel to form high-temperature fuel gas, and transport the high-temperature fuel gas to the fuel turbine 10 to drive the fuel turbine 10 to rotate.

[0043] The oxidant turbine 12 is used to drive the oxidant turbine 12 to rotate using the high-temperature fuel gas output by the heat exchanger 11 and the high-temperature fuel gas flowing out of the fuel turbine 10 as power, so that the oxidant turbine 12 drives the oxidant pump 14 to work.

[0044] The high-temperature fuel gas obtained by the heat exchanger 11 heating the fuel from the fuel pump 13 is also used to converge with the high-temperature fuel gas that passes through the fuel turbine 10 and the oxidant turbine 12 in sequence and then enter the gas generator.

[0045] The present invention also includes: a precooler 15, the precooler 15 has an air flow path inlet, an air flow path outlet, a fuel flow path inlet, and a fuel flow path outlet; the air flow path inlet of the precooler 15 is connected to the intake duct outlet; the air flow path outlet of the precooler 15 is connected to the inlet of the compressor 19; the fuel flow path inlet of the precooler 15 is connected to the outlet of the fuel pump 13; the fuel flow path outlet of the precooler 15 is connected to the cold source inlet of the heat exchanger 11.

[0046] The precooler 15 is used to cool the high-temperature incoming air using the low-temperature fuel from the fuel pump 13, so that the temperature of the incoming air is reduced and then delivered to the compressor 19, and then the low-temperature fuel is heated and then delivered to the heat exchanger 11 for further heat exchange.

[0047] The present invention also includes: a precombustion chamber 16, the precombustion chamber 16 has a fuel inlet, a fuel outlet, and an air inlet; the fuel inlet of the precombustion chamber 16 is connected to the fuel gas outlet of the main turbine 18; the fuel outlet of the precombustion chamber 16 is connected to the heat source inlet of the heat exchanger 11; the air inlet of the precombustion chamber 16 is connected to the outlet of the compressor 19; the precombustion chamber 16 is used for pre-combustion of high-temperature fuel gas from the main turbine 18 and air and then transporting them to the heat exchanger 11; and heating the fuel from the fuel pump 13 in the heat exchanger 11.

[0048] The present invention also includes: a combustion chamber 17, the combustion chamber 17 has a gas inlet and an air inlet; the gas inlet of the combustion chamber 17 is connected to the gas outlet of the ATR's main turbine 18; the air inlet of the combustion chamber 17 is connected to the heat source outlet of the heat exchanger 11; the combustion chamber 17 is used for the complete combustion of the fuel-rich gas from the main turbine 18 that has been cooled by the heat exchanger 11 and the air from the compressor 19.

[0049] The preferred fuel of the present invention is liquid methane. The present invention has two working modes:

[0050] The first working mode is the turbine mode, such as Figure 1 As shown, the specific working principle is:

[0051] The incoming air enters the air inlet duct. At this time, the airflow at the outlet of the air inlet duct is controlled by two switching valves to flow to the compressor 19. A precooler 15 is provided in front of the compressor 19 to cool the incoming air. The low-temperature liquid methane in the fuel tank is pressurized by the fuel pump 13, and the liquid methane is controlled by the conversion valve to flow to the precooler 15. The low-temperature liquid methane and the high-temperature incoming air complete heat exchange in the precooler 15. In order to make the methane obtain more heat and vaporize to drive the fuel turbine 10, the methane that completes the heat exchange in the precooler 15 continues to flow to the heat exchanger 11. The low-temperature methane and the high-temperature combustion gas after the precombustion chamber 16 complete heat exchange in the heat exchanger 11; then part of the gaseous methane flows to the fuel turbine 10, drives the turbine output shaft to drive the fuel pump 13, and the other part flows directly to the fuel turbine 10, and the control valve controls the methane flow entering the fuel turbine 10 to control its output power. The two gaseous methanes then merge and flow to the oxidant turbine 12. The gaseous methane drives the oxidant turbine 12 and drives the oxidant pump 14 to pump liquid oxygen from the oxidant tank into the gas generator. The last part flows directly to the gas generator. Methane and liquid oxygen burn and react in the gas generator to produce high-temperature fuel-rich gas that flows to the main turbine 18, driving the main turbine 18 to drive the compressor 19 to supercharge the incoming air. Part of the gas after vortexing flows to the combustion chamber 17, and the other part flows to the pre-combustion chamber 16. The control valve in front of the combustion chamber 17 controls the flow of fuel-rich gas into the combustion chamber 17, and all the pressurized air flows to the pre-combustion chamber 16. The fuel-rich gas and the supercharged air burn and react in the pre-combustion chamber 16, and then enter the heat exchanger 11 to heat the liquid methane. Finally, all the gas enters the combustion chamber 17 for mixed combustion, and the high-temperature gas is discharged through the tail nozzle.

[0052] The second working mode is the stamping mode, such as Figure 2 As shown, the specific working principle is:

[0053] The incoming air enters the intake duct, and at this time, the two switching valves control the airflow direction of the intake duct outlet to flow to the pre-combustion chamber 16. The low-temperature liquid methane in the fuel tank is pressurized by the fuel pump 13 and flows to the heat exchanger 11. The low-temperature liquid methane and the high-temperature combustion gas complete heat exchange in the heat exchanger 11, and the liquid methane is vaporized by heat. After that, a part of the gaseous methane flows to the fuel turbine 10, and drives the output shaft of the fuel turbine 10 to drive the fuel pump 13. This part of the gaseous methane merges with the remaining part of the gaseous methane and directly enters the combustion chamber 17 and the pre-combustion chamber 16; the methane fuel flowing into the pre-combustion chamber 16 and the air after the intake duct pressurization are burned and reacted in the pre-combustion chamber 16, and the high-temperature combustion gas is generated and flows to the heat exchanger 11 to heat the liquid methane. Then the high-temperature combustion gas flows to the combustion chamber 17 and further burns and reacts with the methane fuel flowing into the combustion chamber 17, and the high-temperature combustion gas is discharged through the tail nozzle.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A methane precooling gas generator cycle turbine enhanced combined power system, characterized in that: include: A fuel turbine (10) for driving a fuel pump (13); a heat exchanger (11) for providing heat to the fuel from the fuel pump (13), heating the fuel to form high-temperature fuel gas, and delivering the high-temperature fuel gas to the fuel turbine (10) so as to drive the fuel turbine (10) to rotate; an oxidant turbine (12), used to drive the oxidant turbine (12) to rotate by using the high-temperature fuel gas output from the heat exchanger (11) and the high-temperature fuel gas flowing out from the fuel turbine (10) as power, so that the oxidant turbine (12) drives the oxidant pump (14) to work; The high-temperature fuel gas obtained by the heat exchanger (11) heating the fuel from the fuel pump (13) is also used to converge with the high-temperature fuel gas that passes through the fuel turbine (10) and the oxidant turbine (12) in sequence and then enter the gas generator.

2. A methane precooling gas generator cycle turbine enhanced combined power system according to claim 1, characterized in that: Also includes: A precooler (15) having an air flow path inlet, an air flow path outlet, a fuel flow path inlet, and a fuel flow path outlet; Its air flow path inlet is connected to the air intake duct outlet; Its air flow path outlet is connected to the inlet of the compressor (19); Its fuel flow path inlet is connected to the fuel pump (13) outlet; Its fuel flow path outlet is connected to the cold source inlet of the heat exchanger (11); The precooler (15) is used to use low-temperature fuel from the fuel pump (13) to cool the high-temperature incoming air, so that the temperature of the incoming air is reduced and then it is transported to the compressor (19), and then the low-temperature fuel is heated and then transported to the heat exchanger (11) for further heat exchange.

3. A methane precooling gas generator cycle turbine enhanced combined power system according to claim 1, characterized in that: Also includes: A pre-combustion chamber (16) having a fuel inlet, a fuel outlet, and an air inlet; Its fuel inlet is connected to the gas outlet of the main turbine (18); Its fuel outlet is connected to the heat source inlet of the heat exchanger (11); Its air inlet is connected to the outlet of the compressor (19); The pre-combustion chamber (16) is used for pre-combusting the high-temperature combustion gas from the main turbine (18) and air before transmitting them to the heat exchanger (11); and for heating the fuel from the fuel pump (13) in the heat exchanger (11).

4. A methane precooling gas generator cycle turbine enhanced combined power system according to claim 1, characterized in that: Also includes: A combustion chamber (17) having a gas inlet and an air inlet; Its gas inlet is connected to the gas outlet of the main turbine (18) of the ATR; Its air inlet is connected to the heat source outlet of the heat exchanger (11); The combustion chamber (17) is used for fully burning the fuel-rich gas from the main turbine (18) cooled by the heat exchanger (11) and the air from the compressor (19).

Images