A hydrogen fuel cell thermal management system for a fixed-wing aircraft

Abstract

The utility model discloses a kind of hydrogen fuel cell thermal management systems for fixed-wing aircraft, including main pump, skin radiator, electronic tee bend valve and PTC heater;The outlet of main pump is connected to the cooling liquid inlet of fuel cell stack, DC / DC converter and intercooler in parallel;The cooling liquid inlet of air compressor is connected in series with the cooling liquid outlet of DC / DC converter;The cooling liquid outlet of fuel cell stack, DC / DC converter and air compressor is connected after confluence with the inlet of electronic tee bend valve;The first outlet of electronic tee bend valve is connected with the inlet of skin radiator, and the second outlet of electronic tee bend valve is connected with the inlet of PTC heater;The outlet of skin radiator and the outlet of PTC heater are connected with main pump. The utility model integrates heat dissipation function into aircraft skin structure, and realizes lightweight, low power consumption and aerodynamic integration by regulating and controlling cooling liquid circuit, while ensuring the efficient heat dissipation and low-temperature rapid start-up capability of fuel cell system.

Description

Technical Field

[0001] This utility model relates to the field of hydrogen fuel cell system technology, and in particular to a hydrogen fuel cell thermal management system for fixed-wing aircraft. Background Technology

[0002] In the field of aircraft thermal management, traditional thermal management solutions, despite long-term development, still have many limitations and cannot meet the stringent requirements of next-generation hydrogen fuel cell-powered aircraft. Currently, the mainstream technological approaches include three categories: One option is air cooling, which utilizes the ram airflow during flight or a built-in fan to drive air circulation and achieve cooling through convection heat transfer. While it has the advantages of simple structure and high reliability, its cooling efficiency is low. Furthermore, introducing external airflow will disrupt the aerodynamic shape of the aircraft, increase flight drag, and the resulting aerodynamic noise also violates the low-noise design concept of new energy aircraft. It is only suitable for low-power scenarios where thermal management requirements are not high.

[0003] The second option is liquid cooling. Fuel cooling technology absorbs and removes heat through the fuel medium. Although it has been used in traditional aero-engines, this technology is entirely dependent on the fuel system and cannot be applied to pure hydrogen-electric power architectures without fuel. Another coolant circulation solution uses a pump to drive coolants such as ethylene glycol to circulate in a closed loop. Heat exchange is achieved through independently installed liquid-cooled radiators and forced-air-cooled fans. Although it can provide high heat exchange efficiency, its bulky radiator modules, complex piping layout, and high-power fan system significantly increase system weight and space occupation, severely encroaching on the aircraft's payload and drastically shortening flight time. At the same time, external heat dissipation structures can also disrupt aerodynamic integrity, generating additional energy consumption and noise.

[0004] Thirdly, phase change material cooling utilizes the latent heat absorption of the material's phase change process to achieve instantaneous thermal shock buffering. Although it is suitable for short-term heat peak management in high-maneuverability flight, the material cost is extremely high and it cannot provide continuous and stable heat dissipation capabilities, so it cannot be used as the main heat dissipation solution to support the entire operation of the hydrogen fuel cell system.

[0005] In summary, existing thermal management technologies all suffer from significant drawbacks: insufficient efficiency, reliance on traditional power architectures, or excessive weight, high energy consumption, and aerodynamic losses due to additional equipment. For hydrogen fuel cell aircraft, components such as the fuel cell stack, high-power DC / DC converter, and air compressor exhibit high heat density and strong temperature sensitivity. Furthermore, the aircraft platform faces extreme requirements regarding weight, space, and aerodynamic efficiency. Traditional solutions struggle to meet the comprehensive demands for high efficiency, lightweight design, low power consumption, and aerodynamic integration. Therefore, an innovative thermal management system is urgently needed to resolve these contradictions and provide crucial technological support for the development of new energy aircraft. Utility Model Content

[0006] To address the aforementioned technical problems, the purpose of this invention is to provide a thermal management system for hydrogen fuel cells in fixed-wing aircraft. This invention integrates heat dissipation directly into the aircraft skin structure and, through the regulation of the coolant circuit, achieves extreme lightweighting, low power consumption, and aerodynamic integration while ensuring efficient heat dissipation and rapid low-temperature start-up capability of the fuel cell system under all operating conditions.

[0007] To achieve the above-mentioned technical objectives and effects, this utility model is implemented through the following technical solution: A thermal management system for a hydrogen fuel cell in a fixed-wing aircraft includes: a main pump, a skin radiator, an electronic three-way valve, and a PTC heater; the outlet of the main pump is connected in parallel via pipelines to the coolant inlets of the fuel cell stack, a DC / DC converter, and an intercooler; the coolant inlet of the air compressor is connected in series with the coolant outlet of the DC / DC converter; the coolant outlets of the fuel cell stack, the DC / DC converter, and the air compressor converge and are connected to the inlet of the electronic three-way valve. The first outlet of the electronic three-way valve is connected to the inlet of the skin radiator, and the second outlet of the electronic three-way valve is connected to the inlet of the PTC heater; the skin radiator and the PTC heater are arranged in parallel, and the outlet of the skin radiator and the outlet of the PTC heater are both connected to the inlet of the main pump; The skin radiator is integrated into the outer skin plate of the fixed-wing aircraft, and is used to directly exchange heat with the outside air through convection on its outer surface.

[0008] Furthermore, the skin radiator includes a base heat dissipation plate and an outer skin plate; the base heat dissipation plate has coolant flow channels inside.

[0009] Furthermore, the skin heat sink is made of a high thermal conductivity metal material, including aluminum alloy or magnesium alloy.

[0010] Furthermore, the base heat sink is also provided with a heat dissipation enhancement structure, which is a fin array or a heat pipe, and the outer skin plate is attached to the heat dissipation enhancement structure.

[0011] Furthermore, the electronic three-way valve is used to adjust the flow rate ratio of coolant to the skin radiator and the PTC heater according to the inlet or outlet temperature of the fuel cell stack, so as to control the inlet and outlet temperature difference of the fuel cell stack.

[0012] Furthermore, the PTC heater is activated during low-temperature startup to heat the coolant flowing through it, thereby rapidly raising the temperature of the fuel cell system to its rated operating temperature.

[0013] Furthermore, the hydrogen fuel cell thermal management system for fixed-wing aircraft also includes an expansion tank; the expansion tank is connected to the flow path between the outlet of the skin radiator and the inlet of the main pump via a compensation pipeline; the expansion tank is used to contain and compensate for the volume change of the coolant in the system due to thermal expansion and contraction, and to maintain stable system pressure.

[0014] The beneficial effects of this utility model are as follows: (1) This utility model uses the aircraft skin directly as the heat dissipation base and sets a basic heat dissipation plate with cooling channels on its inner side, so that the load-bearing structure and heat dissipation function are integrated, which can achieve significant weight reduction and space saving, and provides key guarantee for improving the aircraft's load capacity and equipment layout freedom.

[0015] (2) This utility model utilizes the direct convection heat exchange between the inherent skin surface of the aircraft and the external airflow, which not only reduces energy consumption, but also maintains the aerodynamic integrity of the fuselage because no additional heat dissipation vents are required, thus avoiding aerodynamic drag losses caused by the heat dissipation system. At the same time, the introduction of the electronic three-way valve allows the coolant to bypass the skin radiator under low heat load and flow through the low-resistance bypass, further reducing the load and energy consumption of the main pump and improving the system's operating efficiency.

[0016] (3) This utility model uses an electronic three-way valve to distribute the flow to the skin radiator (large circulation) and the PTC heater (small circulation) according to the temperature of the fuel cell stack. This ensures that the fuel cell stack is always in the optimal operating temperature range under all operating conditions, which not only improves the power generation efficiency and lifespan, but also solves the industry problem of rapid start-up in low temperature environments. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the hydrogen fuel cell thermal management system of this utility model.

[0018] Figure 2 This is a schematic diagram of the structure of the skin-type heat sink in this utility model.

[0019] Figure 3 This is a schematic diagram of the basic heat sink in this utility model.

[0020] In the diagram, 1: main pump; 2: skin radiator; 21: base heat sink; 211: coolant flow channel; 212: fin array; 22: outer skin plate; 3: electronic three-way valve; 4: PTC heater; 5: fuel cell stack; 6: DC / DC converter; 7: intercooler; 8: air compressor; 9: expansion tank. Detailed Implementation

[0021] The technical solutions of this utility model will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0022] like Figures 1 to 3 A preferred embodiment of a hydrogen fuel cell thermal management system for a fixed-wing aircraft is shown, comprising a main pump 1, a skin radiator 2, an electronic three-way valve 3, and a PTC heater 4; the outlet of the main pump 1 is connected in parallel via pipelines to the coolant inlets of the fuel cell stack 5, the DC / DC converter 6, and the intercooler 7; the coolant inlet of the air compressor 8 is connected in series with the coolant outlet of the DC / DC converter 6; the coolant outlets of the fuel cell stack 5, the DC / DC converter 6, and the air compressor 8 converge and are connected to the inlet of the electronic three-way valve 3; The first outlet of the electronic three-way valve 3 is connected to the inlet of the skin radiator 2, and the second outlet of the electronic three-way valve 3 is connected to the inlet of the PTC heater 4; the skin radiator 2 and the PTC heater 4 are arranged in parallel, and the outlets of the skin radiator 2 and the PTC heater 4 are both connected to the inlet of the main pump 1. The skin radiator 2 is integrated into the outer skin plate 22 of the fixed-wing aircraft, and is used to directly exchange heat with the outside air through convection on its outer surface.

[0023] Specifically, the skin radiator 2 includes a base heat sink 21 and an outer skin plate 22. The outer skin plate 22 can be directly integrated as part of the aircraft's aerodynamic outer shell, achieving deep integration of the heat dissipation structure and the load-bearing skin. This eliminates the mounting base, bracket, and connection interface of traditional independent radiators, significantly reducing system weight and avoiding the disruption of aerodynamic integrity caused by external radiators, thus achieving a high degree of unity between function and structure. The base heat sink 21 can be designed as a structure combining an upper heat sink and a lower heat sink. The base heat sink 21 has internal coolant channels 211, such as... Figure 3 The embodiment of the coolant flow channel 211 shown has a serpentine structure. The skin radiator 2 is made of a high thermal conductivity metal material, preferably an aluminum alloy or a magnesium alloy. These materials have extremely high specific strength (strength / density ratio) and thermal conductivity, enabling them to quickly and evenly conduct heat generated by the internal heat source to the entire outer surface of the skin, greatly improving heat dissipation efficiency and providing a fundamental material guarantee for ensuring the performance of the skin radiator 2.

[0024] The base heat sink 21 is also provided with a heat dissipation enhancement structure, which is preferably a fin array 212 or a heat pipe, and the outer skin plate 22 is attached to the heat dissipation enhancement structure. Figure 2 In the illustrated embodiment, a fin array 212 is provided on the base heat sink 21. The heat dissipation enhancement structure significantly improves the overall heat conduction efficiency and temperature uniformity of the skin heat sink 2. Specifically, the fin array 212 enhances heat exchange capacity by significantly increasing the effective heat dissipation area; the heat pipes eliminate localized overheating through high-speed directional heat transfer, ensuring that heat is rapidly distributed across the entire skin surface.

[0025] The electronic three-way valve 3 is used to adjust the flow rate ratio of coolant to the skin radiator 2 and the PTC heater 4 according to the inlet or outlet temperature of the fuel cell stack 5. By adjusting the coolant loop flow rate ratio, the inlet and outlet temperature difference of the fuel cell stack 5 is controlled. The PTC heater 4 starts during low-temperature startup to heat the coolant flowing through it, so that the fuel cell system can quickly heat up to the rated operating temperature.

[0026] The hydrogen fuel cell thermal management system for fixed-wing aircraft also includes an expansion tank 9; the expansion tank 9 is connected to the flow path between the outlet of the skin radiator 2 and the inlet of the main pump 1 via a compensation pipeline; the expansion tank 9 is used to contain and compensate for the volume change of the coolant in the system due to thermal expansion and contraction, and to maintain stable system pressure.

[0027] The hydrogen fuel cell thermal management system for fixed-wing aircraft also includes a temperature sensor located at the coolant outlet of the fuel cell stack 5 and a temperature sensor located at the coolant inlet of the fuel cell stack 5 (not shown in the figure).

[0028] The hydrogen fuel cell thermal management system for fixed-wing aircraft also includes a control unit electrically connected to an electronic three-way valve 3, a PTC heater 4, and a temperature sensor. This control unit receives temperature signals and controls the opening of the electronic three-way valve 3 and the start / stop of the PTC heater 4. This control unit is prior art, employing an open-source controller, model PX4.

[0029] During system operation, the main pump 1 acts as the power source, driving the coolant to circulate throughout the loop. The coolant first flows in parallel through the three core heat-generating components—the fuel cell stack 5, the DC / DC converter 6, and the intercooler 7—efficiently absorbing the heat they generate. The coolant flowing from the DC / DC converter 6 then continues in series through the air compressor 8 for cooling. The high-temperature coolant, after absorbing heat, converges and flows to the electronic three-way valve 3. The control unit monitors the inlet and outlet temperatures of the fuel cell stack 5 in real time and sends commands to the electronic three-way valve 3 accordingly. When the system temperature is normal or too high, the electronic three-way valve 3 adjusts its opening, guiding most or all of the high-temperature coolant to the skin radiator 2. As part of the aircraft's outer skin, this radiator's large surface area directly contacts the high-speed airflow, dissipating heat into the atmosphere through efficient convection heat transfer, rapidly reducing the coolant temperature. When the ambient temperature is extremely low or the system requires a cold start, the electronic three-way valve 3 changes the flow path, allowing the coolant to bypass the skin radiator 2 and flow into the PTC heater 4 instead. The PTC heater 4 is energized and heats up, actively heating the coolant. The heated coolant then flows back into the fuel cell stack 5, rapidly raising its temperature to its rated high-efficiency operating temperature as quickly as possible. Under partial load or transitional operating conditions, the electronic three-way valve 3 can precisely proportionally adjust the coolant flow, diverting one portion to the skin radiator 2 for cooling and the other to the PTC heater 4 for heating or direct bypass. By adjusting the flow ratio of these two portions, precise control of coolant temperature recovery is achieved, thereby stabilizing the inlet and outlet temperature difference of the fuel cell stack 5 within the optimal range.

[0030] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention.

[0031] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A hydrogen fuel cell thermal management system for a fixed-wing aircraft, characterized in that, include: The system includes a main pump, a skin radiator, an electronic three-way valve, and a PTC heater. The outlet of the main pump is connected in parallel via pipelines to the coolant inlets of the fuel cell stack, the DC / DC converter, and the intercooler. The coolant inlet of the air compressor is connected in series with the coolant outlet of the DC / DC converter. The coolant outlets of the fuel cell stack, the DC / DC converter, and the air compressor converge and are then connected to the inlet of the electronic three-way valve. The first outlet of the electronic three-way valve is connected to the inlet of the skin radiator, and the second outlet of the electronic three-way valve is connected to the inlet of the PTC heater; the skin radiator and the PTC heater are arranged in parallel, and the outlet of the skin radiator and the outlet of the PTC heater are both connected to the inlet of the main pump; The skin radiator is integrated into the outer skin plate of the fixed-wing aircraft, and is used to directly exchange heat with the outside air through convection on its outer surface.

2. The hydrogen fuel cell thermal management system for a fixed-wing aircraft according to claim 1, characterized in that, The skin radiator includes a base heat sink and an outer skin; the base heat sink has coolant channels inside.

3. The hydrogen fuel cell thermal management system for a fixed-wing aircraft according to claim 1, characterized in that, The skin heat sink is made of a high thermal conductivity metal material, including aluminum alloy or magnesium alloy.

4. A hydrogen fuel cell thermal management system for a fixed-wing aircraft according to claim 2, characterized in that, The base heat sink is also provided with a heat dissipation enhancement structure, which is a fin array or a heat pipe, and the outer skin plate is attached to the heat dissipation enhancement structure.

5. A hydrogen fuel cell thermal management system for a fixed-wing aircraft according to claim 1, characterized in that, The electronic three-way valve is used to adjust the flow rate ratio of coolant to the skin radiator and the PTC heater according to the inlet or outlet temperature of the fuel cell stack, so as to control the inlet and outlet temperature difference of the fuel cell stack.

6. A hydrogen fuel cell thermal management system for a fixed-wing aircraft according to claim 1, characterized in that, The PTC heater starts during low-temperature startup to heat the coolant flowing through it, thereby rapidly raising the temperature of the fuel cell system to its rated operating temperature.

7. A hydrogen fuel cell thermal management system for a fixed-wing aircraft according to claim 1, characterized in that, It also includes an expansion tank; the expansion tank is connected to the flow path between the outlet of the skin radiator and the inlet of the main pump through a compensation pipe; the expansion tank is used to contain and compensate for the volume change of the coolant in the system due to thermal expansion and contraction, and to maintain the stability of the system pressure.

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