Hybrid supersonic engine using ammonia working medium

Abstract

The invention provides a hybrid supersonic engine using an ammonia working medium. The hybrid supersonic engine comprises an engine body, an air inlet channel, a precooler, a fuel pump, an air compressor, a fuel turbine, a combustion chamber, a spray pipe and a motor, wherein the air inlet channel, the precooler, the fuel pump, the air compressor, the fuel turbine, the combustion chamber, the spray pipe and the motor are arranged in the engine body in a matched mode. The spray pipe is arranged on one side of the combustion chamber; airflow generated by combustion in the combustion chamber is sprayed out from the spray pipe; the hybrid supersonic engine further comprises a fuel cell and a storage battery which are arranged in the engine body. Fuel precooling is carried out on incoming flow air sucked by an engine during high-speed flight, the power needed by a gas compressor is greatly reduced, reactants of chemical reactions of a fuel cell and a combustion chamber are preheated, multiple purposes are achieved, and the whole set of hybrid power system scheme is closed; and meanwhile, a hybrid power system is formed through organic fusion of combustion of a storage battery fuel cell and ammonia fuel in a combustion chamber, power implementation is more diversified, and the power requirements of the aircraft in all flight stages can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft engine manufacturing, and in particular to a hybrid power supersonic engine using ammonia as a working medium. Background Art

[0002] For wide-range high-speed flight in the atmosphere, the use of combined power can achieve relatively efficient performance at an economical cost. In a typical flight mission, it is generally necessary to go through different stages such as take-off, climb, cruise, and descent, and the instantaneous energy requirements of these processes vary greatly. When providing a single type of fuel engine for the above-mentioned flight missions, it is often necessary to take into account the maximum power output condition, which is bound to cause waste and inefficiency to a certain extent. The higher requirements for working capabilities in larger airspace and wider speed ranges require the entire combined power system to operate in a larger variable operating range, and the design difficulty increases sharply. Although advanced combined power technology research continues to be hot, most of it focuses on turbines, rockets, ramjets, and organic combinations of them that quickly and violently release and convert the chemical energy of fuel into mechanical energy. How to maximize the total energy conversion efficiency, how to achieve the adaptability, high reliability and component matching of the engine to a wide range of variable operating conditions, and how to optimize the multi-objective performance of the complex nonlinear system of the engine remain to be solved. Especially when long-range and long-sleep time are placed in front of designers as additional constraints, the challenge of the problem is further increased.

[0003] On the other hand, from the perspective of green and sustainable development, the policy requirements for energy conservation and emission reduction are becoming increasingly stringent, and the necessity and urgency of reducing carbon emissions and increasing efficiency in the aerospace industry are very prominent. Therefore, for high-speed, supersonic and even hypersonic aircraft, developing carbon-free, green, environmentally friendly and efficient power system solutions should become one of the future design goals.

[0004] In view of the two major demands of effectively breaking through the development bottleneck of wide-range combined power and energy conservation and emission reduction, it is urgent to expand the types of combined power primitive engines with good technical development potential, and continuously optimize the combination of primitive engines and coordinated working modes in combination with usage scenarios, so as to effectively reduce the design difficulty of individual components, reduce the number of components, and improve the robustness of the entire power system while achieving efficient, clean, high-speed and wide-range propulsion.

[0005] Here, a "battery-fuel cell-internal combustion engine" intake hybrid system with ammonia as the main working fluid is proposed to achieve the above purpose. In addition, in order to achieve more efficient wide-range combined power integrated energy management, fuel regeneration cooling, turbine-less (turbiness) and fuel air precooling technologies are integrated.

[0006] Currently, there is no carbon-free green hybrid solution in the field of supersonic / hypersonic (above Mach 5) air-breathing aerospace engines.

[0007] The combination of battery and fuel cell has been proven to be well complementary in the ground transportation industry. This pure electric combination has been initially applied in low-speed aircraft, but there are two major obstacles that must be overcome in the face of high-speed aerospace flight scenarios. One is the mismatch between the relatively low power density of fuel cells and the high power demand of high-speed flight, and the other is how to effectively convert electrical energy into mechanical energy and propulsion under supersonic flight conditions. The net power demand for high-speed flight can be reflected by the product of flight resistance and speed. Compared with subsonic flight, the drag coefficient of supersonic flight is larger, and the speed is several times higher, so the power demand can be an order of magnitude or more. Although some types of fuel cells can have an efficiency of more than 60%, ahead of internal combustion engines with an efficiency of only over 40%, the power density of solid-state fuel cell stacks at the current level is at least one order of magnitude smaller than that of traditional energy conversion components such as turbines and internal combustion engines. Batteries or capacitors with higher power density have lower energy density. In general, relying on pure electricity cannot meet the long-term supersonic / hypersonic flight requirements of aircraft, and it is bound to be combined with internal combustion engines to form a hybrid power system to meet the above-mentioned wide-range efficient flight requirements. When building a new hybrid power system, on the one hand, it is necessary to control the power consumption as much as possible, such as the power to drive the compressor; on the other hand, it is necessary to simplify and comprehensively optimize from the system level to achieve the "one piece, multiple functions" of the core components, while reducing the number of auxiliary components, connectors and the extra weight, volume and loss they bring. The efficiency advantage of fuel cells over traditional internal combustion engines of ~20% can be fully utilized. In the past, the application research on SOFC to construct power components was mostly based on hydrogen and hydrocarbons, and the technology of reforming hydrocarbon fuels to produce hydrogen fuel cells still has carbon emission problems. However, hydrogen has a low density, and its use conditions require high pressure and low temperature technology, as well as hydrogen embrittlement.

[0008] To sum up, it is necessary to make further innovations on existing technologies. Summary of the invention

[0009] In view of the technical problems existing in the above-mentioned background technology, the present invention proposes a hybrid supersonic engine using ammonia as a working fluid, which precools the incoming air sucked in by the engine during high-speed flight, thereby not only greatly reducing the power required by the compressor, but also preheating the fuel cell and the reactants of the chemical reaction in the internal combustion chamber, thereby achieving multiple goals at one stroke, so that the entire hybrid power system solution can be closed; at the same time, a hybrid power system is formed by the organic integration of battery-ammonia fuel cell-internal combustion engine, and the power is more diverse, which can meet the power requirements of the aircraft in various flight stages.

[0010] In order to solve the above technical problems, the present invention provides a hybrid supersonic engine using ammonia as a working medium, comprising an engine body and an air inlet, a precooler, a fuel pump, a compressor, a fuel turbine, a combustion chamber, a nozzle and an electric motor matched and arranged in the engine body; the outer wall of the combustion chamber is provided with a cooling structure; the nozzle is matched and arranged at one side of the combustion chamber, and the airflow generated by combustion in the combustion chamber is ejected from the nozzle; the hybrid supersonic engine also includes a fuel cell and a battery arranged in the engine body;

[0011] The air inlet is used to introduce high-speed incoming air into the engine body;

[0012] The feed end of the fuel pump is connected to the discharge port of the fuel storage tank through a fuel pipeline to pump the liquid ammonia fuel in the fuel storage tank into the cooling channel of the precooler to precool the incoming air of the intake duct;

[0013] The power input end of the compressor is matched and connected with the power output end of the motor, and the power output end of the compressor is matched and connected with a fuel turbine;

[0014] The precooler is filled with liquid ammonia output by the fuel pump as a coolant to precool the high-speed incoming air from the intake duct, and the liquid ammonia also absorbs heat and heats up; the fuel cell is fed with precooled air from the precooler;

[0015] The precooler passes the ammonia after absorbing heat and heating into the cooling structure of the outer wall of the combustion chamber through the discharge pipe to provide thermal protection for the wall surface of the combustion chamber, and the ammonia is further preheated by the combustion chamber; a part of the preheated ammonia is passed into the fuel cell through the discharge pipe to react with the precooled air introduced to generate electricity, and the reaction products are passed into the inner cavity of the combustion chamber for efficient combustion, and the other part of the preheated ammonia fuel can be used as a supplementary fuel to selectively drive the fuel turbine to work and finally enter the inner cavity of the combustion chamber; in the inner cavity of the combustion chamber, the reactants of the fuel cell, the pressurized air introduced by the compressor, and the part of the ammonia fuel preheated by the combustion chamber are fully burned together to generate power;

[0016] The fuel cell is electrically connected to the battery and the electric motor respectively; the fuel pump and the compressor are driven by the electric motor; the electric energy generated by the fuel cell is supplied to the electric motor, and if there is surplus electric energy, it enters the battery for storage; the electric motor is also electrically connected to the battery, so that the electric motor can be powered by one of the fuel cell and the battery or both at the same time.

[0017] The hybrid supersonic engine using ammonia as a working medium, wherein: a heat exchange structure is provided in the wall surface of the combustion chamber.

[0018] The hybrid supersonic engine using ammonia as a working fluid, wherein: the aircraft needs to achieve a long hovering time during the subsonic flight phase, and the hybrid supersonic engine can use the fuel cell and the battery to simultaneously power the electric motor, so that the electric motor drives the propeller to achieve long hovering flight of the aircraft.

[0019] The hybrid supersonic engine using ammonia as the working fluid has a relatively large demand for instantaneous output power when the aircraft takes off, and the hybrid supersonic engine can supply power to the electric motor solely through the battery.

[0020] The hybrid supersonic engine using ammonia as a working fluid, wherein: in the low subsonic cruise stage of the aircraft, the hybrid supersonic engine can preheat the fuel cell to the operating temperature through the battery, and after the fuel cell is fully started, the electric energy output by the fuel cell can be used to supply the electric motor, and the battery can also be charged with the surplus power of the fuel cell to achieve range extension.

[0021] The hybrid supersonic engine using ammonia as a working fluid, wherein: when the aircraft needs to end subsonic cruise, the aircraft using the hybrid supersonic engine can separate the first and second stages, the propeller of the first stage is driven by the battery, and the return landing is realized to realize autonomous power recovery, after which the battery can be combined with a new second stage to prepare for the next flight mission after being charged or replaced on the ground and undergoing simple maintenance, thereby realizing the repeatability of the first stage; when the aircraft needs to accelerate from subsonic cruise to high subsonic speed until the ammonia fuel in the combustion chamber is ignited, the fuel cell works at full load and has no residual power output; the second stage after safe separation realizes transonic, supersonic and even hypersonic flight by a hybrid power combination of the battery, the fuel cell and the combustion of ammonia fuel in the combustion chamber; the combustion of ammonia fuel in the combustion chamber provides direct power for the aircraft in the supersonic flight stage, and the electric energy required for the compressor and the fuel pump is provided by the fuel cell.

[0022] The hybrid supersonic engine using ammonia as a working fluid, wherein: when the aircraft is in the low supersonic section, the thermodynamic cycle of the hybrid supersonic engine is powered by the fuel cell for the fuel pump; the power for driving the compressor can be completely provided by the fuel cell when the design pressure ratio value is low; if the compressor pressure ratio requirement is high, a portion of the electric energy is provided by the remaining power of the fuel cell, and when the fuel cell is still insufficient to provide the power required to drive the compressor under full working conditions, the remaining shortfall can be completed by combining the high-temperature ammonia expansion cycle working mode after ammonia fuel is used to cool the compressor interstages and the combustion chamber and nozzle regenerative cooling.

[0023] The hybrid supersonic engine using ammonia as a working fluid, wherein: when the aircraft is in a supersonic section with a higher speed, the hybrid supersonic engine pumps liquid ammonia fuel as a coolant into the precooler through the fuel pump to precool the high-speed incoming air from the inlet duct, so that the temperature of the incoming air compressed by the inlet duct increases only slightly and the density is still relatively large, thereby greatly reducing the power required for the compressor during supersonic flight; the role of the liquid ammonia fuel in the cooling structure of the precooler and the outer wall of the combustion chamber is to preheat the reactants for the fuel cell; the precooler is also a preheater for the fuel in the fuel cell.

[0024] By adopting the above technical solution, the present invention has the following beneficial effects:

[0025] The present invention precools the incoming air sucked by the engine during high-speed flight, which not only greatly reduces the power required by the compressor, but also preheats the reactants of the fuel cell and the combustion chamber chemical reaction, achieving multiple goals at one stroke, so that the entire hybrid power system solution can be closed; at the same time, the hybrid power system is organically integrated through the battery fuel cell-ammonia fuel combustion in the combustion chamber, and the power is more diverse, which can meet the power requirements of the aircraft at various flight stages. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 This is a schematic diagram of the hybrid supersonic engine using ammonia as a working medium according to the present invention;

[0028] Notes:

[0029] I N-inlet, PC-precooler, FP-fuel pump, CP-compressor, FT-fuel turbine, CB-combustion chamber, HE-heat exchanger, NZ-nozzle, FC-fuel cell, BAT-battery, M-motor. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The present invention is further explained below in conjunction with specific implementation modes.

[0032] like Figure 1 As shown, the present embodiment provides a hybrid supersonic engine using ammonia as a working fluid, including an engine body and an air inlet IN, a precooler PC, a fuel pump FP, a compressor CP, a fuel turbine FT, a combustion chamber CB, a heat exchanger HE, a nozzle NZ, a fuel cell FC, a battery BAT and an electric motor M matched and arranged on the engine body.

[0033] The air inlet IN is matched and arranged at the head of the engine body, and is used for introducing high-speed incoming air into the engine body.

[0034] The feed end of the fuel pump FP is connected to the discharge port of the fuel storage tank fue l, and the discharge end pumps the liquid ammonia fuel in the fuel storage tank fue l into the precooler PC through a fuel pipeline.

[0035] The precooler PC is matched and connected to one side of the air outlet of the air inlet IN; the precooler PC is filled with ammonia output by the fuel pump FP as a coolant to precool the high-speed incoming air from the air inlet IN, so that the temperature of the incoming air compressed by the air inlet IN is limited to increase, and the density is still relatively large, thereby greatly reducing the power required by the compressor CP during supersonic flight of the aircraft.

[0036] The fuel cell FC is matched and arranged on one side of the air outlet of the precooler PC, and the precooled air from the precooler PC is introduced into the fuel cell FC. The wall of the combustion chamber CB is provided with a heat exchange structure HE, i.e., a plurality of heat exchange holes. The fuel cell FC passes the product of ammonia fuel and air into the inner cavity of the combustion chamber CB through a pipeline for combustion reaction, and heat is exchanged in the plurality of heat exchange holes in the wall of the combustion chamber CB. The fuel cell FC is electrically connected to the battery BAT and the motor M respectively. The fuel pump FP and the compressor CP are driven by the motor M. The electric energy generated by the fuel cell FC is supplied to the motor M, and if there is any surplus electric energy, it is passed into the battery BAT for storage.

[0037] The precooler PC is filled with liquid ammonia output by the fuel pump FP as a coolant to precool the high-speed incoming air from the intake duct IN, and the liquid ammonia also absorbs heat and heats up; the precooler PC passes the ammonia after absorbing heat and heating into the cooling structure of the outer wall of the combustion chamber CB through the discharge pipe to thermally protect the wall surface of the combustion chamber CB, and the ammonia is further preheated by the combustion chamber CB; a part of the preheated ammonia is passed into the fuel cell FC through the discharge pipe to react with the precooled air introduced to generate electricity, and the reaction products are passed into the inner cavity of the combustion chamber CB for efficient combustion, and the other part of the preheated ammonia fuel can be used as a supplementary fuel to selectively drive the fuel turbine FT to do work and finally enter the inner cavity of the combustion chamber CB; in the inner cavity of the combustion chamber CB, the reactants of the fuel cell FC, the pressurized air introduced by the compressor CP and the part of the ammonia fuel preheated by the combustion chamber CB are fully burned together to generate power.

[0038] The battery BAT and the motor M are matched and arranged on one side of the fuel cell FC; wherein the motor M is also electrically connected to the battery BAT, so that the motor M can be powered by one of the fuel cell FC and the battery BAT or both at the same time.

[0039] The power input end of the compressor CP is matched and connected with the power output end of the motor M, and the power output end of the compressor CP is matched and connected with a fuel turbine FT. The fuel turbine FT is passively rotated by the airflow generated by the combustion in the combustion chamber CB on the one hand, and is driven to rotate by the compressor CP on the other hand.

[0040] The nozzle NZ is matched and arranged at one side of the combustion chamber CB, and the airflow generated by the combustion in the combustion chamber CB is ejected from the nozzle NZ.

[0041] Based on the new understanding in the academic community, that is, the performance of ammonia fuel cells is comparable to that of methane or even hydrogen fuel cells, ammonia is used as the main working fluid in the present invention to realize the above concept. However, due to the difficulty in igniting ammonia and the low flame propagation speed, using pure ammonia itself as the only fuel for internal combustion engines to achieve full combustion and thrust generation is a bottleneck problem that must be solved. After ammonia is decomposed, due to the presence of product hydrogen, efficient injection, mixing, and combustion can be achieved, which can not only greatly improve the flame propagation speed and flame stabilization range, reduce the difficulty of ignition, but also effectively shorten the size and weight of the combustion chamber. Ammonia fuel SOFC actually integrates the catalytic cracker with the catalytic electrochemical reactor to a high degree. Through good design and technical iteration, it can even achieve self-sustaining reaction. Its anode product naturally contains an ammonia-hydrogen mixture, which is very beneficial for the subsequent organization of wide-range efficient combustion, and the aforementioned problems are solved.

[0042] The core principle of the "battery-fuel cell-internal combustion engine" air-breathing hybrid system proposed by the present invention with ammonia as the main working fluid is as follows:

[0043] Inlet IN, precooler PC, fuel pump FP, compressor CP, fuel turbine FT, combustion chamber CB, nozzle NZ, electric motor M, fuel cell FC and battery BAT;

[0044] To achieve a long hovering time during the subsonic flight phase, it is possible to consider using only the "battery BAT-fuel cell FC" part to drive the motor M to drive the propeller, achieving high specific impulse and high fuel economy. During takeoff, the demand for instantaneous output power is relatively large, and the battery BAT can be used to power the motor M. In theory, the capacity of the battery BAT only needs to slightly exceed the sum of the energy required during the takeoff phase. The power demand during the low and medium subsonic cruise phase is significantly lower than that during the takeoff period, so the battery BAT can be used to preheat the fuel cell FC to the operating temperature. After the fuel cell FC is fully started, the motor can be driven by the electric energy output by the fuel cell FC. The battery BAT can also be charged with the remaining power of the fuel cell FC to achieve extended range.

[0045] When it is necessary to end the subsonic cruise, the aircraft using the hybrid power system can separate the first and second stages. The first stage is driven by the partially charged battery BAT to drive the propeller, and the return landing realizes autonomous power recovery. After that, it can be charged or replaced on the ground, and after simple maintenance, it can be combined with the new second stage to prepare for the next flight mission, so that the first stage can be reused. In order to reduce the dead weight of the aircraft, the above-mentioned separation of most of the power batteries has achieved a significant reduction in the load for transonic and supersonic flights. When it is necessary to accelerate from subsonic cruise to high subsonic speed until the ammonia fuel in the combustion chamber CB is ignited, the fuel cell FC can be made to work at full load without residual power output. After safe separation, the second stage is a hybrid power combination of the battery BAT, the fuel cell FC and the ammonia fuel in the combustion chamber CB to achieve transonic, supersonic and even hypersonic flight. The ammonia fuel in the combustion chamber CB provides direct power in the supersonic flight stage, and the power required by other components such as the compressor CP and the fuel pump FP is provided by the fuel cell FC. In this way, at least complex components such as the gas generator and even the turbine can be omitted, and the system level is simplified and optimized again.

[0046] In the thermodynamic cycle of the engine working in the low supersonic section (such as Mach number 1.2-2.5), the fuel cell FC supplies power to the fuel pump FP. The power to drive the compressor CP can be fully provided by the fuel cell FC when the design pressure ratio is low; if the pressure ratio requirement is high, part of it is provided by the remaining power of the fuel cell FC. When the fuel cell FC is working at full capacity and is still insufficient to provide the power required to drive the compressor CP, the remaining shortfall can be completed by combining the high-temperature ammonia expansion cycle working mode after ammonia fuel interstage cooling of the compressor CP, combustion chamber CB and nozzle CB regeneration cooling, but a fuel turbine FT needs to be introduced at this time. Since the ignition and combustion of pure ammonia is more difficult than hydrocarbon fuels, it has always been a hot research topic. However, due to the introduction of ammonia fuel fuel cell FC, the main product includes hydrogen with excellent combustion performance, which solves this problem well.

[0047] In the supersonic section with higher speed (such as Mach number greater than 2.5), ammonia is used as a coolant to precool the high-speed incoming air, so that the temperature of the incoming air after compression through the inlet IN is limited and the density is still relatively large, thereby greatly reducing the power required by the compressor CP during supersonic flight. The main function of ammonia in the cooling structure of the air precooler PC and the outer wall of the combustion chamber CB is to preheat the reactants for the fuel cell FC. The precooler PC is also a preheater for the fuel in the fuel cell FC, combining the two into one to achieve system-level integration optimization. After that, the fuel cell FC generates electricity to drive the compressor CP and the fuel pump FP, and the fuel cell FC product mixture that may contain unreacted fuel is passed into the combustion chamber CB, and is fully burned with the pressurized air and another part of the fuel to generate thrust in the form of an internal combustion engine. It is possible to choose to discharge a part of the unnecessary fuel cell FC product exhaust gas (non-polluting components) directly into the atmosphere. After pre-cooling, a part of the fuel that absorbs heat and rises in temperature enters the fuel cell FC and enters the combustion chamber CB in the form of a mixture of components such as ammonia, hydrogen, nitrogen, and water, serving as the core combustion zone for ignition and flame stabilization, while generating electricity for the entire machine; the other part can be used as supplementary fuel to selectively drive the fuel turbine FT or directly enter the combustion chamber CB, and flexibly match with the core combustion zone to generate the power required for high-speed flight.

[0048] The present invention precools the fuel of the incoming air sucked in by the engine during high-speed flight, which not only greatly reduces the power required by the compressor, but also preheats the fuel cell and the reactants of the chemical reaction in the internal combustion chamber, thereby achieving multiple goals at one stroke, thereby closing the entire hybrid power system solution; at the same time, the hybrid power system is formed by the organic integration of battery-ammonia fuel cell-internal combustion engine, and the power is more diverse, which can meet the power requirements of the aircraft in various flight stages.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hybrid supersonic engine using ammonia as a working medium, comprising an engine body and an inlet duct (IN), a precooler (PC), a fuel pump (FP), a compressor (CP), a fuel turbine (FT), a combustion chamber (CB), a nozzle (NZ) and a motor (M) matched and arranged in the engine body; the outer wall of the combustion chamber (CB) is provided with a cooling structure; the nozzle (NZ) is matched and arranged on one side of the combustion chamber (CB), and the airflow generated by combustion in the combustion chamber (CB) is ejected from the nozzle (NZ); characterized in that: The hybrid supersonic engine further comprises a fuel cell (FC) and a battery (BAT) disposed in the engine body; The air inlet (IN) is used to introduce high-speed incoming air into the engine body; The feed end of the fuel pump (FP) is connected to the discharge port of the fuel storage tank (fuel) through a fuel pipeline to pump the liquid ammonia fuel in the fuel storage tank (fuel) into the cooling channel of the precooler (PC) to precool the incoming air of the intake duct (IN); The power input end of the compressor (CP) is matched and connected with the power output end of the motor (M), and the power output end of the compressor (CP) is matched and connected with a fuel turbine (FT); The precooler (PC) is filled with liquid ammonia output by the fuel pump (FP) as a coolant to precool the high-speed incoming air from the intake duct (IN), and the liquid ammonia also absorbs heat and heats up; the fuel cell (FC) is fed with the precooled air from the precooler (PC); The precooler (PC) passes the ammonia after absorbing heat and heating into the cooling structure of the outer wall of the combustion chamber (CB) through the discharge pipe to provide thermal protection for the wall surface of the combustion chamber (CB), and the ammonia is further preheated by the combustion chamber (CB); a part of the preheated ammonia is passed into the fuel cell (FC) through the discharge pipe to react with the precooled air introduced to generate electricity, and the reaction products are passed into the inner cavity of the combustion chamber (CB) for efficient combustion, and another part of the preheated ammonia fuel can be used as a supplementary fuel to selectively drive the fuel turbine (FT) to do work and finally enter the inner cavity of the combustion chamber (CB); in the inner cavity of the combustion chamber (CB), the reactants of the fuel cell (FC) are fully burned together with the pressurized air introduced by the compressor (CP) and a part of the ammonia fuel preheated by the combustion chamber (CB) to generate power; The fuel cell (FC) is electrically connected to the battery (BAT) and the electric motor (M) respectively; the fuel pump (FP) and the compressor (CP) are driven by the electric motor (M); the electric energy generated by the fuel cell (FC) is supplied to the electric motor (M), and if there is surplus electric energy, it enters the battery (BAT) for storage; the electric motor (M) is also electrically connected to the battery (BAT), so that the electric motor (M) can be powered by one of the fuel cell (FC) and the battery (BAT) or both at the same time.

2. The hybrid supersonic engine using ammonia as claimed in claim 1, characterized in that: A heat exchange structure (HE) is provided in the wall of the combustion chamber (CB).

3. The hybrid supersonic engine using ammonia as a working medium according to claim 1, characterized in that: In order to achieve a long hovering time in the subsonic flight phase of the aircraft, the hybrid supersonic engine can use the fuel cell (FC) and the battery (BAT) to simultaneously power the electric motor (M), so that the electric motor (M) drives the propeller to achieve long hovering flight of the aircraft.

4. The hybrid supersonic engine using ammonia as a working medium according to claim 1, characterized in that: When the aircraft takes off, the demand for instantaneous output power is relatively large, and the hybrid supersonic engine can supply power to the electric motor (M) solely through the battery (BAT).

5. The hybrid supersonic engine using ammonia as claimed in claim 1, characterized in that: During the low-subsonic cruise phase of the aircraft, the hybrid supersonic engine can preheat the fuel cell (FC) to the operating temperature through the battery (BAT), and after the fuel cell (FC) is fully started, the electric energy output by the fuel cell (FC) can be used to supply the electric motor (M), and the battery (BAT) can also be charged with the surplus power of the fuel cell (FC) to achieve range extension.

6. The hybrid supersonic engine using ammonia as a working medium according to claim 1, characterized in that: When the aircraft needs to end subsonic cruise, the aircraft using the hybrid supersonic engine can separate the first stage and the second stage, the first stage is driven by the battery (BAT) to drive the propeller, and the return landing is performed to realize autonomous power recovery. After that, the battery (BAT) can be charged or replaced on the ground and simply maintained before it can be combined with a new second stage to prepare for the next flight mission, thereby realizing the repeatability of the first stage; when the aircraft needs to accelerate from subsonic cruise to high subsonic speed until the ammonia fuel in the combustion chamber (CB) is ignited, the fuel cell (FC) works at full load and has no residual power output; after safe separation, the second stage is realized by a hybrid power combination of the battery (BAT), the fuel cell (FC) and the combustion of ammonia fuel in the combustion chamber (CB) to realize transonic, supersonic and even hypersonic flight; the combustion of ammonia fuel in the combustion chamber (CB) provides direct power for the aircraft in the supersonic flight stage, and the fuel cell (FC) provides the electric energy required by the compressor (CP) and the fuel pump (FP).

7. The hybrid supersonic engine using ammonia as a working medium according to claim 1, characterized in that: When the aircraft is in the low supersonic section, the thermodynamic cycle of the hybrid supersonic engine is powered by the fuel cell (FC) for the fuel pump; the power for driving the compressor (CP) can be completely provided by the fuel cell (FC) when the design pressure ratio value is low; if the pressure ratio requirement of the compressor (CP) is high, part of the electric energy is provided by the remaining power of the fuel cell (FC), and when the fuel cell (FC) is working at full capacity and is still insufficient to provide the power required to drive the compressor (CP), the remaining shortfall can be completed by combining the high-temperature ammonia expansion cycle working mode after the interstage cooling of the compressor (CP) and the regenerative cooling of the combustion chamber (CB) and the nozzle (NZ) using ammonia fuel.

8. The hybrid supersonic engine using ammonia as a working medium according to claim 1, characterized in that: When the aircraft is in a supersonic section with a higher speed, the hybrid supersonic engine pumps liquid ammonia fuel as a coolant into the precooler (PC) through the fuel pump (FP) to precool the high-speed incoming air from the inlet (IN), so that the temperature of the incoming air compressed by the inlet (IN) increases only slightly and the density is still relatively large, thereby greatly reducing the power required by the compressor (CP) during supersonic flight; the role of the liquid ammonia fuel in the cooling structure of the precooler (PC) and the outer wall of the combustion chamber (CB) is to preheat the reactants for the fuel cell (FC); the precooler (PC) is also a preheater for the fuel in the fuel cell (FC).

Images