Efficient power generation device for air-breathing hypersonic vehicle

Abstract

The application discloses a kind of high-efficiency power generation devices of air-breathing hypersonic aircraft, including being arranged in the reformer of air-breathing hypersonic aircraft and SOFC system, air inlet hole is equipped on the wall of inlet duct, and air inlet hole is communicated with the oxidant inlet of SOFC system;Supersonic combustion chamber is equipped with fuel inlet hole and fuel outlet hole on the wall, fuel inlet hole is connected with the air inlet end of reformer, the air outlet end of reformer is communicated with the fuel inlet of SOFC system, and the product outlet of SOFC system is communicated with fuel outlet hole.The application is applied to the field of aerospace energy generation technology, chemical energy is directly converted into electric energy by electrochemical reaction process using the feature that SOFC does not need to take force, not limited by Carnot cycle, thereby improve energy conversion efficiency, not only reduce pollutant emission, but also meet the demand of high electric power ratio and long time online power supply flight task, can be effectively applied to air-breathing hypersonic aircraft.

Description

Technical Field

[0001] This invention relates to the field of aerospace energy generation technology, specifically a high-efficiency power generation device for air-breathing hypersonic vehicles, and more particularly to a device for generating electricity using a solid oxide fuel cell by utilizing the electrochemical reaction between high-temperature compressed air in the air intake and hydrocarbon fuel in an air-breathing hypersonic vehicle. Background Technology

[0002] High-power, high-density, and efficient energy generation and management are crucial for achieving long endurance and reusability in future air-breathing hypersonic vehicles. Air-breathing hypersonic vehicles primarily use scramjet engines for power generation, but lack continuously operating rotating components for online power generation, posing a challenge to energy supply during flight. Furthermore, carrying high-power battery packs presents a contradiction between extremely high peak power demands and balanced energy supply. Developing efficient online energy generation technologies for aircraft is a key approach to resolving these challenges and contradictions. In traditional gas turbine systems, chemical energy is first converted into thermal energy, then into mechanical energy, and finally into electrical energy.

[0003] To achieve efficient energy generation, scholars have proposed a series of development ideas. One patent, CN210105994U, describes a combined power generation system and device using a microtubular solid oxide fuel cell (SOFC). This system integrates SOFC with a micro gas turbine, effectively increasing electrical energy while reducing the exhaust gas temperature of the SOFC system. However, the required integrated system is complex and utilizes a compressor to provide high-pressure gas to the battery cathode, making it unsuitable for long-range high-speed flight. Another patent, CN110056429B, describes a distributed hybrid propulsion system using a solid oxide fuel cell and gas turbine for aircraft. This system employs a core-separated distributed propulsion system to address long flight time and high power supply requirements. However, considering the use of a turbine propulsion device, it adds a rotor system, and the flight speed is only Mach 0.8, which is insufficient for supersonic aircraft. Therefore, existing SOFC-based hybrid propulsion systems cannot be effectively applied to air-breathing hypersonic aircraft. Summary of the Invention

[0004] To address the problems of excessive weight and insufficient online power generation in existing technologies using conventional batteries, and the lack of a rotor device in scramjet engines, this invention provides a high-efficiency power generation device for air-breathing hypersonic vehicles. Utilizing the non-power-take-off characteristic of SOFCs, chemical energy is directly converted into electrical energy through an electrochemical reaction process, without being limited by the Carnot cycle, thereby improving energy conversion efficiency. This not only reduces pollutant emissions but also meets the requirements of high power-to-electricity ratio and long-endurance online power supply flight missions, and can be effectively applied to air-breathing hypersonic vehicles.

[0005] To achieve the above objectives, the present invention provides a high-efficiency power generation device for an air-breathing hypersonic vehicle, wherein the air-breathing hypersonic vehicle has an air intake, an isolation section, a combustion chamber and a tail nozzle connected in sequence.

[0006] The power generation device includes a reformer and an SOFC system located inside the air-breathing hypersonic vehicle, and the SOFC system is electrically connected to the electrical components inside the air-breathing hypersonic vehicle.

[0007] The wall of the air intake duct is provided with an air intake hole, and the air intake hole is connected to the oxidant inlet of the SOFC system.

[0008] The combustion chamber wall is provided with a fuel inlet and a fuel outlet. The fuel inlet is connected to the inlet end of the reformer, the outlet end of the reformer is connected to the fuel inlet of the SOFC system, and the product outlet of the SOFC system is connected to the fuel outlet.

[0009] In one embodiment, the combustion chamber has a recess, the fuel inlet is disposed on the leading edge wall or side wall of the recess, and the fuel outlet is disposed on the leading edge wall or combustion chamber wall at a position corresponding to the upstream of the recess.

[0010] In one embodiment, the fuel inlet is connected to the inlet of the reformer via a heat exchanger;

[0011] The heat exchanger is connected to the fuel injection pipeline of the combustion chamber to exchange heat and cool the fuel gas inside the heat exchanger.

[0012] In one embodiment, the SOFC system is composed of several SOFC battery cells connected in series.

[0013] In one embodiment, it also includes an air intake manifold, a fuel intake manifold, and a fuel exhaust manifold;

[0014] One end of the air intake manifold is connected to the air intake hole, and the other end is connected to the oxidant inlet of each SOFC battery cell through air intake branch pipes.

[0015] One end of the fuel intake manifold is connected to the outlet of the reformer, and the other end is connected to the fuel inlet of each SOFC battery cell through fuel intake branch pipes.

[0016] One end of the fuel exhaust manifold is connected to the fuel outlet, and the other end is connected to the product outlet of each SOFC battery cell through a fuel exhaust branch pipe.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects:

[0018] 1. This invention provides electrical energy to the SOFC system by diverting fuel from the combustion chamber of a ramjet engine, ensuring real-time and efficient energy generation during supersonic flight;

[0019] 2. When the air-breathing aircraft operates at hypersonic speed, the air temperature of the boundary layer of the aircraft's air intake can reach 1200K, which meets the operating temperature of the SOFC system cathode. This allows the SOFC system to generate electricity autonomously and efficiently within the aircraft without consuming additional energy to heat the working medium temperature of the battery cathode.

[0020] 3. In this invention, the fuel temperature in the combustion chamber of the aircraft can reach the operating temperature of the SOFC system after regeneration and cooling, which provides fuel for the anode operation of the SOFC system. Moreover, the gas discharged from the SOFC system after the operation is completed can be transported back to the combustion chamber of the ramjet engine, so as not to affect the fuel efficiency of the aircraft while ensuring the power generation efficiency of SOFC.

[0021] 4. The air-breathing hypersonic vehicle power generation device used in this invention has the characteristics of simple installation structure, no need for rotating complex parts, and high power generation efficiency. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0023] Figure 1 This is an overall structural diagram of the high-efficiency power generation device for an air-breathing hypersonic vehicle in an embodiment of the present invention.

[0024] Reference numerals: SOFC system 1, heat exchanger 2, cavity 3, intake duct 4, isolation section 5, combustion chamber 6, tail nozzle 7, reformer 8, turbo pump 9, air intake port 10, fuel intake port 11.

[0025] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0028] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0029] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two elements or the interaction between two elements, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0030] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0031] This embodiment discloses a high-efficiency power generation device for an air-breathing hypersonic vehicle. It involves mounting a SOFC system 1 and a reformer 8 (a micro-reformer) on the air-breathing hypersonic vehicle. Utilizing the non-power-take-off characteristic of the SOFC system 1, the chemical energy of the air in the intake duct 4 and the fuel gas in the combustion chamber 6 is directly converted into electrical energy through an electrochemical reaction process. This provides continuous power to the air-breathing hypersonic vehicle during high-electricity-to-power ratio, long-endurance online power supply missions, without being limited by the Carnot cycle, thus improving energy conversion efficiency and reducing pollutant emissions.

[0032] refer to Figure 1 The air-breathing hypersonic vehicle has an air intake duct 4, an isolation section 5, a combustion chamber 6, and a tail nozzle 7 connected in sequence, forming the internal flow channel of the engine. The air intake duct 4 provides inlet velocity for stable combustion while ensuring sufficient flow resistance within permissible limits. In this embodiment, to ensure that the air intake section of the combustion chamber 6 captures the required airflow, the air intake duct 4 can generally be a two-dimensional air intake, a three-dimensional side-pressure air intake, or an axisymmetric air intake. The isolation section 5 adopts a constant cross-section or an expanded configuration, and the incoming gas flows through the air intake section before connecting to the isolation section 5 to avoid shock wave interference. The combustion chamber 6 is located after the isolation section 5, and the combustion chamber 6 adopts a concave cavity 3 structure to improve combustion efficiency and engine thrust. In this embodiment, the combustion chamber 6 uses a high-temperature and high-pressure resistant material to reduce the impact of high temperatures on the material inside the combustion chamber 6, avoid deformation leading to changes in the gas passage structure, and improve the service life of the combustion chamber 6. That is, after the external air enters the engine through the intake duct 4, it forms high temperature and high pressure air. Then it flows through the isolation section 5 to avoid shock wave interference, and then mixes and burns with the injected fuel in the concave cavity 3 of the combustion chamber 6. Finally, it is discharged from the tail nozzle 7.

[0033] The reformer 8 and SOFC system 1 are both located inside the aircraft, and SOFC system 1 is electrically connected to the electrical components inside the aircraft to provide continuous power supply for air-breathing hypersonic aircraft during high electrical ratio and long-endurance online power supply flight missions.

[0034] An air intake hole 10 is provided on the wall of the air intake duct 4, and the air intake hole 10 is connected to the oxidant inlet of the SOFC system 1, so that the boundary layer gas of the air intake duct 4 flows into the oxidant inlet and cathode layer of the SOFC system 1 through the air intake hole 10. Since the air-breathing aircraft operates at hypersonic speed, the air temperature in the boundary layer of the air intake duct 4 can exceed 1200K, which meets the operating temperature of the cathode of the SOFC system 1. This allows the SOFC system 1 to generate electricity autonomously and efficiently in the aircraft without consuming additional energy to heat the working medium temperature of the battery cathode.

[0035] The supersonic combustion chamber 6 has a fuel inlet 11 on its wall. The fuel inlet 11 is located on the front edge or side wall of the cavity 3. The fuel inlet 11 is connected to the inlet end of the reformer 8 through a pipeline. A turbopump 9 is installed on the pipeline between the fuel inlet 11 and the inlet end of the reformer 8 to draw gas from the combustion chamber 6 to the reformer 8. The outlet end of the reformer 8 is connected to the fuel inlet of the SOFC system 1. The fuel inlet 11 and the inlet end of the reformer 8 are connected to the fuel inlet 2 through a heat exchanger to cool the fuel. The channel of the heat exchanger 2 is in contact with the fuel injection pipeline of the combustion chamber 6 to exchange heat and cool the fuel gas in the heat exchanger 2. The turbopump 9 is located on the pipeline behind the heat exchanger 2. The heat exchanger 2 cools the fuel gas temperature in the combustion chamber 6 from over 1500℃ to the 600-1000℃ required for the anode operation of the SOFC system 1. Simultaneously, it preheats the fuel in the fuel injection pipeline of the combustion chamber 6. The process is as follows: the fuel gas (including gasified kerosene, CO, H2, CO2, etc.) in the combustion chamber 6 enters the heat exchanger 2 through the fuel inlet 11. After heat exchange, the temperature is reduced to 600-1000℃ before entering the reformer 8. After reforming in the reformer 8, methane and / or hydrogen are output and then transported to the anode layer of the SOFC system 1.

[0036] A fuel outlet 12 is also provided on the wall of the supersonic combustion chamber 6. The fuel outlet 12 is located on the wall of the isolation section 5 or the combustion chamber 6 or the leading edge wall of the cavity 3. The product outlet of the SOFC system 1 is connected to the fuel outlet 12, so that the fuel gas discharged after the electrochemical reaction of the SOFC system 1 is transferred back to the front of the cavity 3 through the fuel outlet 12 and the injector with a circular nozzle or array structure and then flows back into the combustion chamber 6 system. This improves the power generation efficiency of the air-breathing hypersonic vehicle without wasting fuel, and at the same time, it does not affect the fuel efficiency of the vehicle while ensuring the power generation efficiency of SOFC. As a preferred embodiment, the fuel outlet 12 and the fuel injection port of the combustion chamber 6 can also be combined into one, that is, the fuel gas discharged after the electrochemical reaction of the SOFC system 1 and the fuel of the combustion chamber 6 are injected into the combustion chamber 6 through the same injector.

[0037] In summary, the power generation device in this embodiment utilizes the combustion chamber 6 of the aircraft engine to provide high-temperature fuel, and reduces the fuel temperature to the required operating temperature of the fuel cell anode layer through the heat exchanger 2. Within the operating temperature range, the fuel gas in the combustion chamber 6 is converted into the gas required by the fuel cell anode through the reformer 8. At the same time, high-pressure air from the boundary layer of the intake duct 4 is extracted and passed through the fuel cell cathode. The air in the pipeline is regulated to the required flow rate of the cathode layer of the SOFC system 1 through the control system. After the SOFC system 1 is in operation, it provides power to the air-breathing hypersonic engine. It is not only simple in structure and has high power generation efficiency, but also, for the first time, couples the SOFC system 1 and the ramjet engine to provide power to an air-breathing hypersonic aircraft.

[0038] In this embodiment, the SOFC system 1 is composed of several SOFC cells connected in series, wherein the SOFC cells are either planar SOFCs or tubular SOFCs. In specific implementation, the SOFC system 1 is composed of multiple battery stacks, with each stack connected in series by connectors. Each stack consists of 20 planar solid oxide fuel cells, requiring approximately 5600-9000 stacks to supply 50-80 kW of auxiliary power to the air-breathing aircraft. More specifically, the oxidant inlet and outlet of the planar SOFC are located on its left and right sides, respectively, while the fuel inlet and product outlet are located on its upper and lower sides, respectively. The oxidant inlet and outlet are symmetrically distributed along the left-right direction on the planar SOFC, and the fuel inlet and product outlet are symmetrically distributed along the upper-lower direction, which facilitates a symmetrical distribution of static pressure during the SOFC's intake and exhaust processes.

[0039] In practical implementation, the power generation unit also includes an air intake manifold, a fuel intake manifold, and a fuel exhaust manifold. Specifically, one end of the air intake manifold is connected to the air intake port 10, and the other end is connected to the oxidant inlet of each SOFC cell via air intake branch pipes; one end of the fuel intake manifold is connected to the outlet of the reformer 8, and the other end is connected to the fuel inlet of each SOFC cell via fuel intake branch pipes; one end of the fuel exhaust manifold is connected to the fuel outlet port 12, and the other end is connected to the product outlet of each SOFC cell via fuel exhaust branch pipes. That is:

[0040] The boundary layer gas from the intake duct 4 of the compressor engine flows into the air intake manifold through the air intake port 10, and then reaches the oxidant inlet of the individual fuel cell cathode layer through each air intake branch pipe. It is discharged from the oxidant outlet at a position symmetrical to the oxidant inlet, which is beneficial to the symmetrical distribution of static pressure in the exhaust process of SOFC. The fuel gas in the combustion chamber 6 enters the heat exchanger 2 through the fuel intake port 11. After heat exchange, it is reduced to 600-1000℃ and then enters the reformer 8. After the reforming reaction in the reformer 8, methane and / or hydrogen are transported to the fuel intake manifold, and then reach the fuel inlet of the individual fuel cell anode layer through each fuel intake branch pipe. The fuel gas discharged after the electrochemical reaction of the flat-plate SOFC reaches the fuel exhaust manifold through each fuel exhaust branch pipe, and finally is transmitted to the front of the cavity 3 through the fuel exhaust port and flows back to the combustion chamber 6 system. This improves the power generation efficiency of the air-breathing hypersonic vehicle without wasting fuel.

[0041] In practical implementation, planar SOFCs can be electrolyte-supported, cathode-supported, or anode-supported; this embodiment uses an anode-supported SOFC. To ensure stable operation of the planar SOFC and withstand sudden power changes and various thermal shocks under high temperature and high pressure, its materials need to have high mechanical strength. For example, yttrium-stabilized zirconium oxide (YSZ) can be used as the electrolyte, lanthanum manganese strontium oxide as the cathode, and nickel / zirconium oxide cermet (Ni / YSZ) as the anode, which is beneficial to improving the discharge stability of the battery and increasing the battery's output power density.

[0042] It should be noted that the working environment of flat-plate SOFC battery stacks is relatively harsh. Therefore, flexible connectors are used in the connectors to facilitate the connection and sealing between individual cells. At the same time, the I-rib structure is used to improve mechanical strength and ensure structural stability in high-temperature environments. The rib material needs to have strong oxidation resistance and good pressure resistance.

[0043] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A high-efficiency power generation device for air-breathing hypersonic vehicles, the air-breathing hypersonic vehicles having an air inlet, a isolator, a combustion chamber and a nozzle connected in sequence; the power generation device comprising a reformer and a SOFC system arranged inside the air-breathing hypersonic vehicles, and the SOFC system being electrically connected to electrical components inside the air-breathing hypersonic vehicles; the air inlet being provided with an air inlet hole on its wall surface, and the air inlet hole being connected to an oxidant inlet of the SOFC system; the combustion chamber being provided with a fuel inlet hole and a fuel outlet hole on its wall surface, the fuel inlet hole being connected to an air inlet end of the reformer, an air outlet end of the reformer being connected to a fuel inlet of the SOFC system, and a product outlet of the SOFC system being connected to the fuel outlet hole; the combustion chamber having a cavity, the fuel inlet hole being arranged on a leading edge wall surface or a side wall surface of the cavity, and the fuel outlet hole being arranged on a wall surface of the isolator or the combustion chamber, or the fuel outlet hole being arranged on the leading edge wall surface of the cavity; the fuel inlet hole being connected to the air inlet end of the reformer through a heat exchanger, and the heat exchanger being connected to a fuel injection pipeline of the combustion chamber in contact to perform heat exchange to cool fuel gas in the heat exchanger; the SOFC system being composed of a plurality of SOFC cell monomers connected in series. characterized in that The power generation device further comprises an air inlet manifold, a fuel inlet manifold and a fuel outlet manifold; one end of the air inlet manifold being connected to the air inlet hole, and the other end being connected to oxidant inlets of the SOFC cell monomers through air inlet branch pipes; one end of the fuel inlet manifold being connected to the air outlet end of the reformer, and the other end being connected to fuel inlets of the SOFC cell monomers through fuel inlet branch pipes; and one end of the fuel outlet manifold being connected to the fuel outlet hole, and the other end being connected to product outlets of the SOFC cell monomers through fuel outlet branch pipes. ​ ​ ​ ​ 2. The air-breathing hypersonic vehicle high-efficiency power generation device of claim 1, wherein, ​ 3. The air-breathing hypersonic vehicle high-efficiency power generation device of claim 2, wherein, ​ ​ ​ ​

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