Methane pre-cooled gas generator cycle turbo augmented combined power system

Abstract

The present invention discloses a methane pre-cooling gas generator cycle turbine enhanced combined power system, comprising: a fuel turbine, a heat exchanger for providing heat for the fuel from a fuel pump and delivering the high-temperature fuel gas to the fuel turbine so as to drive the fuel turbine to rotate; an oxidizer turbine for driving the oxidizer turbine to rotate with 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 oxidizer turbine drives the oxidizer pump to work; the high-temperature fuel gas obtained after the heat exchanger heats the fuel from the fuel pump is also used to converge with the high-temperature fuel gas that passes through the fuel turbine and the oxidizer turbine in sequence and then enter the gas generator; 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 operating Mach number of the turbine core engine to above Ma3.5. The matching ramjet mode only needs to take into account the operating speed range above Ma3.5, and its working performance can be better released.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of aerospace propulsion, and particularly relates to a methane pre-cooling gas generator cycle turbo-augmented combined power system. BACKGROUND

[0002] An air turbo rocket (ATR) engine is an air-breathing propulsion system with partial oxidizer, which combines a turbine engine and a rocket engine. Main components of the ATR engine include a compressor, a gas generator, a turbine, a combustion chamber and a nozzle. During operation, high-temperature rich fuel gas generated by the gas generator drives the turbine, which in turn drives the compressor to pressurize the incoming air. The pressurized air and the rich fuel gas passing through the turbine are mixed and burned in the combustion chamber to produce high-temperature gas, which is accelerated and ejected through the nozzle to generate thrust. The specific impulse of the ATR engine is higher than that of the rocket engine, and the thrust-to-weight ratio is higher than that of the turbine engine. Moreover, the ATR engine has a large thrust regulation range and moderate technical difficulty.

[0003] However, as the flight Mach number increases, the total temperature of the incoming air rises, which reduces the cycle heating and the engine thrust output. On the other hand, due to the temperature limitation of the compressor, the actual pressure ratio provided by the compressor decreases, and the core engine composed of the compressor and the rocket turbine contributes little to the thrust at high Mach numbers, becoming dead weight of the engine.

[0004] To address this issue, pre-cooling technology can be used to cool the incoming air, reduce the total temperature of the incoming air, and increase the pressure ratio at high Mach numbers, thereby improving the performance of the engine and expanding its operating speed range. In the prior art, the indirect pre-cooling engine represented by the Synergic Air-breathing-Rocket Engine (SABRE) of Reaction Engines Limited has made great progress and breakthroughs in cycle schemes, key technologies and principle prototype development. Most of the research uses liquid hydrogen as fuel and pre-cooling agent, which has the advantages of good cooling performance, no carbon deposition and coking, but the use temperature is low, it is difficult to store for a long time, the price is expensive, and the high-temperature and high-pressure hydrogen fuel in the pipeline may cause hydrogen embrittlement of the heat exchanger material. Hydrogen leakage from the pre-cooler poses a safety risk. SUMMARY

[0005] The purpose of the present application is to provide a methane pre-cooling gas generator cycle turbo-augmented combined power system to solve the problem of using liquid hydrogen as fuel and pre-cooling agent, which has a low use temperature, is difficult to store for a long time, is expensive, and the high-temperature and high-pressure hydrogen fuel in the pipeline may cause hydrogen embrittlement of the heat exchanger material. Hydrogen leakage from the pre-cooler poses a safety risk.

[0006] The present application adopts the following technical solution: a methane pre-cooling gas generator cycle turbo-augmented combined power system, comprising:

[0007] a fuel turbine for driving the fuel pump to work;

[0008] a heat exchanger for heating the fuel from the fuel pump, and forming high-temperature fuel gas after heating the fuel, and delivering the high-temperature fuel gas to the fuel turbine, so as to drive the fuel turbine to rotate;

[0009] an oxidant turbine for driving the oxidant pump to work by the high-temperature fuel gas output by the heat exchanger and the high-temperature fuel gas flowing out from the fuel turbine.

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

[0011] Further, it further comprises:

[0012] a pre-cooler, having an air flow path inlet, an air flow path outlet, a fuel flow path inlet, and a fuel flow path outlet;

[0013] The air flow path inlet of the pre-cooler is in communication with the outlet of the air inlet duct.

[0014] The air flow path outlet of the pre-cooler is in communication with the inlet of the compressor.

[0015] The fuel flow path inlet of the pre-cooler is in communication with the outlet of the fuel pump.

[0016] The fuel flow path outlet of the pre-cooler is in communication with the cold source inlet of the heat exchanger.

[0017] The pre-cooler is used to cool the high-temperature incoming air by using the low-temperature fuel from the fuel pump, so that the temperature of the incoming air is reduced and then delivered to the compressor, and the low-temperature fuel is heated and then delivered to the heat exchanger for re-heating.

[0018] Further, it further comprises:

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

[0020] The fuel inlet of the pre-chamber is in communication with the gas outlet of the main turbine.

[0021] The fuel outlet of the pre-chamber is in communication with the heat source inlet of the heat exchanger.

[0022] The air inlet of the pre-chamber is in communication with the outlet of the compressor.

[0023] The pre-chamber is used to pre-burn the high-temperature gas from the main turbine and the air, and then deliver them to the heat exchanger, and heat the fuel from the fuel pump in the heat exchanger.

[0024] Further, it further comprises:

[0025] The combustion chamber is provided with a gas inlet and an air inlet;

[0026] The gas inlet of the combustion chamber is communicated with the gas outlet of the main turbine of the ATR;

[0027] The air inlet of the combustion chamber is communicated with the heat source outlet of the heat exchanger;

[0028] The combustion chamber is used for full combustion of the rich combustion gas from the main turbine and the air from the air compressor after the heat exchanger.

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

[0030] The present application keeps the temperature of the air flow at the inlet of the air compressor unchanged or only changes in an allowable range through the pre-cooler, thereby improving the working performance of the engine and widening the working speed range of the engine;

[0031] The engine of the present application uses methane as fuel and pre-cooling agent, and uses liquid oxygen as oxidant, and the liquid oxygen / methane propellant combination has the characteristics of abundant resources, non-toxic and non-polluting, good cooling performance, and strong repeatability;

[0032] The present application uses liquid methane to pre-cool the incoming flow, effectively reduces the total temperature of the incoming flow after the inlet duct, and can expand the upper limit of the working Mach number of the turbine core engine to Ma3.5 or above, and the ram mode only needs to consider the working speed range above Ma3.5, and the working performance can be better released; therefore, the combined engine of the present application can obtain better working performance and wider working range, and can also perform mode conversion at a higher Mach number, at which the ram engine has better performance, and can effectively solve the "thrust gap" problem during mode conversion;

[0033] The liquid methane used to pre-cool the incoming flow in the present application can be used as fuel or pre-cooling agent, and does not need to carry other inert cooling media; during engine operation, the liquid methane with high vaporization latent heat is heated through the pre-cooler and the heat exchanger, and is first used as a working medium to drive the fuel turbine and the oxidant turbine, and then enters the gas generator for subsequent combustion; in the ram mode, the methane after driving the fuel pump directly enters the pre-chamber and the combustion chamber for combustion, so that the liquid methane carried on the combined engine of the present application is fully utilized, which is conducive to reducing the mass of the engine and improving the thrust-to-weight ratio of the engine;

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

[0035] The application has excellent wide-range acceleration capability, and through pre-cooling of the incoming flow, greater compressor pressure ratio can be realized at high Mach number, thereby improving engine performance to obtain greater thrust and specific thrust, and in terms of cruising capability, through faster acceleration process, cruising speed can be reached as soon as possible, and greater cruising distance can also be realized. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 A schematic diagram of a turbine mode of the application;

[0037] Figure 2 A schematic diagram of a ram mode of the application.

[0038] Wherein: 10, fuel turbine; 11, heat exchanger; 12, oxidant turbine; 13, fuel pump; 14, oxidant pump; 15, pre-cooler; 16, pre-chamber; 17, combustion chamber; 18, main turbine; 19, compressor. DETAILED DESCRIPTION

[0039] The application will be described in detail below in conjunction with the drawings and specific embodiments.

[0040] In the description of the application, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application. In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the application, unless otherwise specified, the meaning of "multiple" is two or more. The "trend" in the application is described according to the trend when the application is in the state. Figure 1

[0041] The application discloses a kind of methane pre-cooling gas generator cycle turbofan combined power system, as shown in figure Figure 1 Including: fuel turbine 10, heat exchanger 11, oxidant turbine 12.

[0042] Fuel turbine 10 is used to drive fuel pump 13 to work;Heat exchanger 11 is used to provide heat for fuel from fuel pump 13, high-temperature fuel gas is formed after heating fuel, and high-temperature fuel gas is delivered to fuel turbine 10, so as to drive 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 from 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 merge with the high-temperature fuel gas that passes through the fuel turbine 10 and the oxidizer 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 inlet, an air flow outlet, a fuel flow inlet, and a fuel flow outlet; the air flow inlet of the precooler 15 is connected to the air intake outlet; the air flow outlet of the precooler 15 is connected to the inlet of the compressor 19; the fuel flow inlet of the precooler 15 is connected to the outlet of the fuel pump 13; the fuel flow 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 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 to pre-combust the high-temperature gas from the main turbine 18 and air and then transport them to the heat exchanger 11; and heat 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, and the air flow at the outlet of the air inlet is controlled by two switching valves to flow to the compressor 19. A precooler 15 is arranged 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 controlled by a switching valve to flow to the precooler 15. The low-temperature liquid methane exchanges heat with the high-temperature incoming air in the precooler 15 to obtain more heat and vaporize to drive the fuel turbine 10. The methane that exchanges heat in the precooler 15 continues to flow to the heat exchanger 11, and the low-temperature methane exchanges heat with the high-temperature gas after the precombustion chamber 16 in the heat exchanger 11. Then, part of the gaseous methane flows to the fuel turbine 10 to drive the turbine output shaft to drive the fuel pump 13, and the other part directly flows to the fuel turbine 10 and is controlled by a control valve to control the flow of methane into the fuel turbine 10 to control the power output. The two streams of gaseous methane then converge 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 directly flows to the gas generator. The methane and liquid oxygen burn in the gas generator to produce high-temperature rich gas that flows to the main turbine 18 to drive the main turbine 18 to drive the compressor 19 to pressurize the incoming air. Part of the driven gas flows to the combustion chamber 17, and the other part flows to the precombustion chamber 16. The flow of rich gas into the combustion chamber 17 is controlled by a control valve before the combustion chamber 17, and the pressurized air flows to the precombustion chamber 16. The rich gas and the pressurized air burn in the precombustion chamber 16 and then enter the heat exchanger 11 to heat the liquid methane. Finally, all the gas enters the combustion chamber 17 to mix and burn, and the high-temperature gas is discharged through the tail nozzle.

[0052] The second working mode is the ram mode, as shown in FIG. 2, and the specific working principle is as follows: Figure 2

[0053] The incoming air enters the air inlet, and the air flow at the outlet of the air inlet is controlled by two switching valves to flow to the compressor 19. A precooler 15 is arranged 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 controlled by a switching valve to flow to the precooler 15. The low-temperature liquid methane exchanges heat with the high-temperature incoming air in the precooler 15 to obtain more heat and vaporize to drive the fuel turbine 10. The methane that exchanges heat in the precooler 15 continues to flow to the heat exchanger 11, and the low-temperature methane exchanges heat with the high-temperature gas after the precombustion chamber 16 in the heat exchanger 11. Then, part of the gaseous methane flows to the fuel turbine 10 to drive the turbine output shaft to drive the fuel pump 13, and the other part directly flows to the fuel turbine 10 and is controlled by a control valve to control the flow of methane into the fuel turbine 10 to control the power output. The two streams of gaseous methane then converge 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 directly flows to the gas generator. The methane and liquid oxygen burn in the gas generator to produce high-temperature rich gas that flows to the main turbine 18 to drive the main turbine 18 to drive the compressor 19 to pressurize the incoming air. Part of the driven gas flows to the combustion chamber 17, and the other part flows to the precombustion chamber 16. The flow of rich gas into the combustion chamber 17 is controlled by a control valve before the combustion chamber 17, and the pressurized air flows to the precombustion chamber 16. The rich gas and the pressurized air burn in the precombustion chamber 16 and then enter the heat exchanger 11 to heat the liquid methane. Finally, all the gas enters the combustion chamber 17 to mix and burn, and the high-temperature gas is discharged through the tail nozzle.

[0054] ​The above merely describes preferred embodiments of the present application and is not used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A methane pre-cooling gas generator cycle turbine enhanced combined power system, characterized in that: include: A fuel turbine (10) is used to drive a fuel pump (13); 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 the air is delivered to the compressor (19), and the low-temperature fuel is heated and then delivered to the heat exchanger (11) for further heat exchange; A heat exchanger (11) is used to provide heat to the fuel from the fuel pump (13), heating the fuel to form high-temperature fuel gas; In turbine mode, part of the high-temperature fuel gas flows to the fuel turbine (10), and the other part flows directly to the back of the fuel turbine (10). The flow rate of the high-temperature fuel gas entering the fuel turbine (10) is controlled by a control valve to control the power output thereof. The two streams of high-temperature fuel gas then merge and flow to the oxidizer turbine (12). The high-temperature fuel gas drives the oxidizer turbine (12) and drives the oxidizer pump (14) to pump liquid oxygen from the oxidizer tank into the gas generator. The last part flows directly to the gas generator to generate high-temperature rich fuel gas that flows to the main turbine ((18)). The main turbine (18) is driven to drive the compressor (19) to supercharge the incoming air; a portion of the fuel gas after the vortex is driven flows into the combustion chamber (17), and the other portion flows into the pre-combustion chamber (16). The flow of the rich fuel gas flowing into the combustion chamber (17) is controlled by a control valve in front of the combustion chamber (17), and all the supercharged air flows into the pre-combustion chamber (16); the rich fuel gas and the supercharged air are burned and reacted in the pre-combustion chamber (16), and then enter the heat exchanger (11) to heat the liquid fuel. Finally, all the fuel gas enters the combustion chamber (17) and is mixed and burned to generate high-temperature fuel gas that is discharged through the tail nozzle; In the ramjet mode, a portion of the high-temperature fuel gas flows to the fuel turbine (10), and this portion of the high-temperature fuel gas merges with the remaining portion of the high-temperature fuel gas and directly enters the combustion chamber (17) and the pre-combustion chamber (16); the high-temperature fuel gas flowing into the pre-combustion chamber (16) and the air pressurized by the intake duct are burned in the pre-combustion chamber (16), generating high-temperature combustion gas that flows to the heat exchanger (11) to heat the liquid fuel, and then the high-temperature combustion gas flows to the combustion chamber (17) and further burns and reacts with the fuel flowing into the combustion chamber (17), generating high-temperature combustion gas that is discharged through the tail nozzle; The fuel is methane.

2. The methane pre-cooling 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 to pre-combust high-temperature combustion gas from the main turbine (18) and air before being transported to the heat exchanger (11); and to heat the fuel from the fuel pump (13) in the heat exchanger (11).

3. The methane pre-cooling 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 ATR main turbine (18); 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).

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