Vortex tube-based fuel cell thermal management system

Abstract

The utility model discloses a fuel cell thermal management system based on a vortex tube. The fuel cell thermal management system comprises an electric pile, the vortex tube, a first plate heat exchanger, a second plate heat exchanger and a third plate heat exchanger, a gas inlet of the vortex tube is connected with a stack air outlet, a cold air end outlet is respectively connected with cold side inlets of the first plate heat exchanger and the third plate heat exchanger, and a hot air end outlet is connected with a hot side inlet of the second plate heat exchanger; a hot side inlet of the first plate heat exchanger is connected with compressed air, a hot side outlet is connected with an electric pile air inlet, and a cold side outlet is used as a tail gas discharge end; a cold-side inlet of the second plate heat exchanger is connected with hydrogen, a cold-side outlet is connected with an electric pile hydrogen inlet, and a hot-side outlet is used as a tail gas emission end; a hot-side inlet of the third plate heat exchanger is connected with cooling liquid, a hot-side outlet is connected with an electric pile cooling liquid inlet, and a cold-side outlet is used as a tail gas discharge end. The device can reduce the temperature of air and cooling liquid at an electric pile inlet and improve the heat exchange efficiency of a system.

Description

Technical Field

[0001] This utility model relates to the field of fuel cell technology, and in particular to a fuel cell thermal management system based on vortex tubes. Background Technology

[0002] The fuel cell thermal management system is one of the key subsystems for ensuring the long-term stable operation of fuel cells. In order to ensure cooling efficiency, the fuel cell thermal management system is usually equipped with a number of cooling fans. With the increasing power requirements of fuel cell systems in applications such as heavy trucks, the heat dissipation power of the system also increases. However, the space left by vehicle manufacturers for fuel cell systems is very limited, making it difficult to install enough cooling fans. The high temperature caused by the accumulation of waste heat is one of the main factors leading to the degradation of the membrane electrode performance of the fuel cell stack. Therefore, how to reduce the temperature of the coolant and air at the fuel cell stack inlet is an important direction for the development of new high-efficiency thermal management systems.

[0003] Patent CN218274657U discloses a fuel cell system and vehicle using vortex tubes. The system includes a fuel cell stack, a hydrogen system, and an air system. The fuel cell stack includes an air-side inlet and a hydrogen-side inlet. The hydrogen system includes a heat exchanger and a hydrogen pipeline; the heat exchanger is mounted on the hydrogen pipeline and connected to the hydrogen-side inlet. The air system includes a connected air compressor and a vortex tube; the air compressor includes a cooling inlet, and the vortex tube includes a cold-end outlet and a hot-end outlet. The cold-end outlet is connected to both the cooling inlet and the air-side inlet, and the hot-end outlet is connected to the heat exchanger. However, this patent places the vortex tube at the air compressor outlet, which results in significant energy loss at the air inlet side and a substantial reduction in the air pressure at the fuel cell stack inlet.

[0004] Patent application CN119518016A discloses a fuel cell cooling system based on the vortex tube cooling effect. This system, in sequence, comprises an air compressor, intercooler, humidifier, fuel cell stack, shut-off valve, muffler, three-way valve, and heat dissipation assembly. Its key feature is that it further includes vortex cooling tubes and a plate heat exchanger, with the vortex cooling tubes positioned between the muffler and the shut-off valve. This system connects the cold air generated by the vortex tubes to the plate heat exchanger containing the coolant, then utilizes the coolant to cool the air, resulting in relatively low heat exchange efficiency.

[0005] Patent application CN111490264A discloses a fuel cell assembly comprising: a fuel cell having a first inlet for fuel and a second inlet for oxidant, and a vortex tube having an inlet, a first outlet for heated gas, and a second outlet for cooled gas. Here, the first outlet of the vortex tube is in fluid connection to either the first or second inlet of the fuel cell. However, the primary application of the vortex tube in fuel cells is to adjust oxygen and hydrogen to suitable pressure and temperature, allowing the gas at the appropriate temperature and pressure to enter the fuel cell system for reaction.

[0006] Patent CN209374567U discloses a fuel cell cold start system based on vortex tube heating, including a fuel cell stack, with the cathode of the stack connected to an air supply system. The air supply system includes: a main pipeline, on which a main valve, an intercooler, and a humidifier humidification end are sequentially arranged, the humidifier humidification end being connected to the cathode of the fuel cell stack; branch pipelines, on which branch valves and vortex tubes are arranged, the vortex tubes being connected to the cathode of the fuel cell stack; and an air compressor, the air outlet of which is connected to both the main valve and the branch valve. This system is mainly used in the field of low-temperature cold start. When a cold start is required due to low ambient temperature, the air is diverted through the vortex tube via a bypass valve, separating it into high-temperature gas and low-temperature gas. The high-temperature gas undergoes a chemical reaction in the fuel cell stack, melting the cathode ice, while the low-temperature gas is discharged through the exhaust path. Utility Model Content

[0007] To address the aforementioned issues, this invention proposes a fuel cell thermal management system based on vortex tubes. Considering the high energy remaining in the high-pressure air at the stack exhaust, the system connects the exhaust high-pressure air to the vortex tubes. The cold air generated by the vortex tubes is introduced into a plate heat exchanger to exchange heat with the inlet air and coolant of the fuel cell stack. Conversely, the hot air generated by the vortex tubes is introduced into the plate heat exchanger to exchange heat with the cold hydrogen gas after the pressure reducing valve. This reduces the temperature of the inlet air and coolant, minimizing membrane electrode performance degradation caused by high temperatures and improving the system's heat exchange efficiency. This invention improves the overall system efficiency and reduces membrane electrode performance degradation caused by insufficient system heat dissipation.

[0008] The technical solution adopted in this utility model is as follows:

[0009] A fuel cell thermal management system based on vortex tubes includes a fuel cell stack, vortex tubes, a first plate heat exchanger, a second plate heat exchanger, and a third plate heat exchanger. The gas inlet of the vortex tube is connected to the air outlet of the fuel cell stack, the cold gas outlet is connected to the cold-side inlets of the first and third plate heat exchangers respectively, and the hot gas outlet is connected to the hot-side inlet of the second plate heat exchanger. The hot-side inlet of the first plate heat exchanger is connected to compressed air, the hot-side outlet is connected to the air inlet of the fuel cell stack, and the cold-side outlet serves as the exhaust gas outlet. The cold-side inlet of the second plate heat exchanger is connected to hydrogen, the cold-side outlet is connected to the hydrogen inlet of the fuel cell stack, and the hot-side outlet serves as the exhaust gas outlet. The hot-side inlet of the third plate heat exchanger is connected to coolant, the hot-side outlet is connected to the coolant inlet of the fuel cell stack, and the cold-side outlet serves as the exhaust gas outlet.

[0010] Furthermore, the fuel cell thermal management system also includes a humidifier, the first inlet of which is connected to the fuel cell stack air outlet, the first outlet of which is connected to the gas inlet of the vortex tube, the second inlet of which is connected to compressed air, and the second outlet of which is connected to the fuel cell stack air inlet through the first plate heat exchanger.

[0011] Furthermore, the fuel cell thermal management system also includes an air compressor, the gas inlet of which is connected to air, and the gas outlet of which is connected to the second inlet of a humidifier.

[0012] Furthermore, the fuel cell thermal management system also includes an intercooler, the gas inlet of which is connected to the gas outlet of the air compressor, and the gas outlet of which is connected to the second inlet of the humidifier.

[0013] Furthermore, the fuel cell thermal management system also includes a hydrogen storage tank connected to the cold-side inlet of the second plate heat exchanger.

[0014] Furthermore, the fuel cell thermal management system also includes a safety valve located between the hydrogen storage tank and the second plate heat exchanger.

[0015] Furthermore, the fuel cell thermal management system also includes a pressure reducing valve, which is located between the hydrogen storage tank and the second plate heat exchanger.

[0016] Furthermore, the fuel cell thermal management system also includes a hydrogen ejector, the hydrogen inlet of which is connected to the cold side outlet of the second plate heat exchanger, and the hydrogen outlet is connected to the hydrogen inlet of the fuel cell stack.

[0017] Furthermore, the fuel cell thermal management system also includes a gas-liquid separator, wherein the gas-liquid inlet of the gas-liquid separator is connected to the hydrogen outlet of the fuel cell stack, and the gas outlet is connected to the hydrogen inlet of the fuel cell stack.

[0018] Furthermore, the fuel cell thermal management system also includes a heat dissipation system, one side of which is connected to the stack coolant outlet, and the other side is connected to the stack coolant inlet via a third plate heat exchanger.

[0019] The beneficial effects of this utility model are as follows:

[0020] 1. This invention considers that the high-pressure air at the tail end of the fuel cell stack still has considerable energy that can be utilized. It connects the high-pressure air at the tail end of the stack to a vortex tube. After passing through the vortex tube, the high-pressure air is separated into two streams, one cold and one hot, which flow out from the outlets on both sides of the vortex tube. The cold air generated by the vortex tube is introduced into a plate heat exchanger to exchange heat with the inlet air and coolant of the fuel cell stack. This vortex tube-assisted heat exchange system can significantly reduce the heat dissipation pressure on the cooling fan, further reduce the temperature of the inlet air and coolant of the fuel cell stack, and slow down the degradation of the membrane electrode life caused by high temperatures. Simultaneously, the hot air generated by the vortex tube is introduced into the plate heat exchanger to exchange heat with the cold hydrogen gas after the pressure reducing valve, improving the system's heat exchange efficiency.

[0021] 2. This utility model can introduce the cold air generated by the vortex tube into the plate heat exchanger to directly exchange heat with the inlet air and coolant of the fuel cell stack, and introduce the hot air into the heat exchanger to directly exchange heat with the cold hydrogen, thereby improving the heat exchange efficiency.

[0022] 3. Due to the simple structure, small size and low damage of the vortex tube device, this utility model can reduce the number of cooling fans and improve the volumetric power density of the system by arranging the vortex tubes. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a fuel cell thermal management system based on a vortex tube according to an embodiment of the present invention.

[0024] Reference numerals: 1-Fuel stack, 2-Humidifier, 3-Intercooler, 4-Air compressor, 5-Vortex tube, 6-First plate heat exchanger, 7-Hydrogen storage tank, 8-Safety valve, 9-Pressure reducing valve, 10-Second plate heat exchanger, 11-Hydrogen ejector, 12-Gas-liquid separator, 13-Third plate heat exchanger, 14-Heat dissipation system; 101-Fuel stack air inlet, 102-Fuel stack air outlet, 103-Fuel stack hydrogen inlet, 104-Fuel stack hydrogen outlet, 105-Fuel stack coolant outlet, 106-Fuel stack coolant inlet. Detailed Implementation

[0025] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, specific embodiments are now described. It should be understood that the specific embodiments described herein are merely illustrative of this utility model and are not intended to limit it; that is, the described embodiments are only a part of, and not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0026] like Figure 1 As shown, this embodiment provides a fuel cell thermal management system based on vortex tubes, including a fuel cell stack 1, a vortex tube 5, a first plate heat exchanger 6, a second plate heat exchanger 10, and a third plate heat exchanger 13. The gas inlet of the vortex tube 5 is connected to the air outlet 102 of the fuel cell stack. The cold gas drawn from the vortex tube 5 is connected to the cold-side inlets of the first plate heat exchanger 6 and the third plate heat exchanger 13, respectively. The hot gas drawn from the vortex tube 5 is connected to the hot-side inlet of the second plate heat exchanger 10. The hot-side inlet of the first plate heat exchanger 6 is connected to compressed air, and the hot-side outlet is connected to the air inlet 101 of the fuel cell stack. The cold gas drawn from the vortex tube 5 is discharged as exhaust gas after heat exchange in the first plate heat exchanger 6. The cold-side inlet of the second plate heat exchanger 10 is connected to the depressurized hydrogen gas from the high-pressure gas cylinder 7, and the cold-side outlet is connected to the hydrogen inlet 103 of the fuel cell stack. The hot gas drawn from the vortex tube 5 is discharged as exhaust gas after heat exchange in the second plate heat exchanger 10. The hot-side inlet of the third plate heat exchanger 13 is connected to the coolant outlet of the heat dissipation system 14, and the hot-side outlet is connected to the coolant inlet 106 of the fuel cell stack. The cold gas drawn from the vortex tube 5 is discharged as exhaust gas after heat exchange in the third plate heat exchanger 13.

[0027] It should be noted that after the high-pressure air completes the reaction within the fuel cell stack 1, it is discharged from the fuel cell stack air outlet 102. Since the high-pressure air at the tail end still has considerable energy that can be utilized, it is connected to the vortex tube 5. The airflow rotates and flows towards the hot gas end outlet of the vortex tube 5. The hot gas end outlet of the vortex tube 5 is equipped with a conical baffle. After a portion of the gas is blocked by the conical baffle, it rotates in the opposite direction within the inner circle of the vortex tube 5 and flows towards the cold gas end of the vortex tube 5. During this process, the inner airflow becomes cold and the outer airflow becomes hot, with the cold and hot airflows flowing out from both sides respectively. The cold air generated by the vortex tube 5 is then introduced into the first plate heat exchanger 6 and the third plate heat exchanger 13 to exchange heat with the fuel cell stack inlet air and coolant, respectively. The hot air is introduced into the second plate heat exchanger 10 to exchange heat with the depressurized cold hydrogen.

[0028] Preferably, the fuel cell thermal management system further includes a humidifier 2, the first inlet of which is connected to the stack air outlet 102, the first outlet is connected to the gas inlet of the vortex tube 5, the second inlet is connected to compressed air, and the second outlet is connected to the stack air inlet 101 through the first plate heat exchanger 6.

[0029] Preferably, the fuel cell thermal management system further includes an air compressor 4, with the air compressor 4 having a gas inlet connected to air and a gas outlet connected to the second inlet of the humidifier 2.

[0030] Preferably, the fuel cell thermal management system further includes an intercooler 3, the gas inlet of which is connected to the gas outlet of the air compressor 4, and the gas outlet of the intercooler 3 is connected to the second inlet of the humidifier 2.

[0031] Preferably, the fuel cell thermal management system further includes a hydrogen storage tank 7, which is connected to the cold side inlet of the second plate heat exchanger 10.

[0032] Preferably, the fuel cell thermal management system further includes a safety valve 8, which is disposed between the hydrogen storage tank 7 and the second plate heat exchanger 10.

[0033] Preferably, the fuel cell thermal management system further includes a pressure reducing valve 9, which is disposed between the hydrogen storage tank 7 and the second plate heat exchanger 10.

[0034] Preferably, the fuel cell thermal management system further includes a hydrogen ejector 11, the hydrogen inlet of which is connected to the cold side outlet of the second plate heat exchanger 10, and the hydrogen outlet is connected to the fuel cell stack hydrogen inlet 103.

[0035] Preferably, the fuel cell thermal management system further includes a gas-liquid separator 12, the gas-liquid inlet of which is connected to the hydrogen outlet 104 of the fuel cell stack, and the gas outlet of which is connected to the hydrogen inlet 103 of the fuel cell stack.

[0036] Preferably, the fuel cell thermal management system further includes a heat dissipation system 14, one side of which is connected to the stack coolant outlet 105, and the other side is connected to the stack coolant inlet 106 via a third plate heat exchanger 13.

[0037] In summary, this fuel cell thermal management system fully utilizes the high-pressure air at the stack outlet exhaust, introducing the cold air generated by the vortex tube into the plate heat exchanger to exchange heat with the stack inlet air and coolant, thereby reducing the temperature of the stack inlet air and coolant and minimizing the performance degradation of the membrane electrode assembly caused by high temperatures. By introducing cold air and hot air separately into the heat exchanger to exchange heat with hot air and cold hydrogen, the heat exchange efficiency is improved.

[0038] The above description is merely a preferred embodiment of this utility model. It should be understood that this utility model is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of this utility model should be protected within the scope of the appended claims. Furthermore, the terms "first," "second," and "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.

Claims

1. A fuel cell thermal management system based on eddy tubes, characterized in that, It includes a fuel cell stack (1), a vortex tube (5), a first plate heat exchanger (6), a second plate heat exchanger (10), and a third plate heat exchanger (13). The gas inlet of the vortex tube (5) is connected to the air outlet (102) of the fuel cell stack, the cold gas outlet is connected to the cold side inlet of the first plate heat exchanger (6) and the third plate heat exchanger (13) respectively, and the hot gas outlet is connected to the hot side inlet of the second plate heat exchanger (10). The hot side inlet of the first plate heat exchanger (6) is connected to compressed air, the hot side outlet is connected to the fuel cell air inlet (101), and the cold side outlet is used as the exhaust gas outlet. The cold side inlet of the second plate heat exchanger (10) is connected to hydrogen, the cold side outlet is connected to the hydrogen inlet (103) of the fuel cell stack, and the hot side outlet serves as the exhaust gas outlet. The hot side inlet of the third plate heat exchanger (13) is connected to the coolant, the hot side outlet is connected to the fuel cell coolant inlet (106), and the cold side outlet serves as the exhaust gas outlet.

2. The fuel cell thermal management system based on eddy current tubes according to claim 1, characterized in that, It also includes a humidifier (2), the first inlet of which is connected to the fuel cell air outlet (102), the first outlet is connected to the gas inlet of the vortex tube (5), the second inlet is connected to compressed air, and the second outlet is connected to the fuel cell air inlet (101) through the first plate heat exchanger (6).

3. The fuel cell thermal management system based on eddy current tubes according to claim 2, characterized in that, It also includes an air compressor (4), the gas inlet side of which is the atmosphere, and the gas outlet is connected to the second inlet of the humidifier (2).

4. A fuel cell thermal management system based on eddy current tubes according to claim 3, characterized in that, It also includes an intercooler (3), the gas inlet of which is connected to the gas outlet of the air compressor (4), and the gas outlet of the intercooler (3) is connected to the second inlet of the humidifier (2).

5. A fuel cell thermal management system based on eddy current tubes according to claim 1, characterized in that, It also includes a hydrogen storage tank (7), which is connected to the cold side inlet of the second plate heat exchanger (10).

6. A fuel cell thermal management system based on eddy tubes according to claim 5, characterized in that, It also includes a safety valve (8), which is located between the hydrogen storage tank (7) and the second plate heat exchanger (10).

7. A fuel cell thermal management system based on eddy current tubes according to claim 5, characterized in that, It also includes a pressure reducing valve (9), which is located between the hydrogen storage tank (7) and the second plate heat exchanger (10).

8. A fuel cell thermal management system based on eddy current tubes according to claim 1, characterized in that, It also includes a hydrogen ejector (11), the hydrogen inlet of which is connected to the cold side outlet of the second plate heat exchanger (10), and the hydrogen outlet is connected to the hydrogen inlet (103) of the fuel cell stack.

9. A fuel cell thermal management system based on eddy current tubes according to claim 1, characterized in that, It also includes a gas-liquid separator (12), the gas-liquid inlet of which is connected to the hydrogen outlet (104) of the fuel cell stack, and the gas outlet is connected to the hydrogen inlet (103) of the fuel cell stack.

10. A fuel cell thermal management system based on eddy current tubes according to claim 1, characterized in that, It also includes a heat dissipation system (14), one side of which is connected to the fuel cell coolant outlet (105), and the other side is connected to the fuel cell coolant inlet (106) through a third plate heat exchanger (13).

Images