Ejecting device and hydrogen fuel cell system with same

Abstract

The invention provides an injection device and a hydrogen fuel cell system with the same. The ejection device comprises an ejector; the heat exchange pipeline is arranged on the outer wall of the ejector; a pipe cavity of the heat exchange pipeline is a heat exchange flow channel for a heat exchange medium to circulate; the heat exchange pipeline comprises at least two heat exchange pipe sections, and every two adjacent heat exchange pipe sections communicate with each other and are arranged at intervals. One end of the communicating pipeline is communicated with the ejection inlet of the ejector, and the other end of the communicating pipeline is communicated with a hydrogen source; the communicating pipeline is provided with a communicating pipe section, and the communicating pipe section is arranged on the outer wall of the ejector and located between the two adjacent heat exchange pipe sections so that the two adjacent heat exchange pipe sections can conduct heat exchange with the communicating pipe section. Through the technical scheme provided by the invention, the technical problem that the interior of the ejector in the prior art is easy to freeze can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of ejector devices, and in particular to an ejector device and a hydrogen fuel cell system having the same. Background Art

[0002] At present, hydrogen fuel cell systems are power generation devices that convert hydrogen and oxidants into electrical energy through electrochemical reactions. The anode chamber of hydrogen fuel cells usually adopts a closed circulation process, and the anode chamber circulation system usually uses a hydrogen circulation pump or an ejector as a hydrogen reflux device to improve the utilization rate of hydrogen. Compared with the hydrogen circulation pump, the ejector device has no rotating parts, low operating noise, high reliability, and no energy consumption, making it an ideal device for the fuel cell hydrogen circulation system.

[0003] However, the operating environment temperature of hydrogen fuel cell systems usually ranges from -30℃ to 45℃. During the normal operation of the system, the water generated by the cathode reaction will diffuse into the anode cavity. Although the anode cavity is designed with a drainage device, the cooling after shutdown will cause the gaseous water in the anode cavity to condense into liquid. In an environment below zero degrees, the ejector is prone to internal freezing, resulting in abnormal hydrogen supply of the fuel cell system and failure to operate normally. Summary of the invention

[0004] The main purpose of the present invention is to provide an ejector device and a hydrogen fuel cell system having the same, so as to solve the technical problem of ice formation easily occurring inside the ejector in the prior art.

[0005] In order to achieve the above object, according to one aspect of the present invention, there is provided an ejection device, comprising:

[0006] Ejector;

[0007] The heat exchange pipeline is arranged on the outer wall of the ejector; the lumen of the heat exchange pipeline is a heat exchange flow channel for the heat exchange medium to flow; the heat exchange pipeline includes at least two heat exchange pipe sections, and two adjacent heat exchange pipe sections are interconnected and arranged at intervals;

[0008] A connecting pipeline, one end of which is connected to the ejection inlet of the ejector and the other end of which is connected to the hydrogen source; the connecting pipeline has a connecting pipe section, which is arranged on the outer wall of the ejector and between two adjacent heat exchange pipe sections, so that the two adjacent heat exchange pipe sections can exchange heat with the connecting pipe section.

[0009] Further, the connecting pipeline is spirally wound around the ejector along the extending direction of the ejector, and the spiral section of the connecting pipeline forms a connecting pipeline section; or,

[0010] The connecting pipeline includes at least two connecting pipe sections, each connecting pipe section is an annular structure, two adjacent connecting pipe sections are connected to each other and are arranged at intervals along the extension direction of the ejector, and at least two heat exchange pipe sections and at least two connecting pipe sections correspond to each other and are arranged alternately.

[0011] Further, the heat exchange pipeline is spirally wound around the ejector along the extension direction of the ejector; or,

[0012] Each heat exchange tube segment is an annular structure, and at least two heat exchange tube segments are arranged at intervals along the extension direction of the ejector to form an annular structure. At least part of the ejector is inserted into the annular structure and arranged opposite to the annular structure.

[0013] Furthermore, the ejector includes a mixing portion and a diffusion portion which are interconnected, the mixing portion encloses a mixing chamber, the diffusion portion encloses a diffusion chamber, the cross-sectional flow area of ​​the diffusion chamber gradually increases along the direction from the mixing chamber to the diffusion chamber, and the ejector is also provided with a reflux inlet connected to the reflux hydrogen source, and the reflux inlet and the ejection inlet are both connected to the mixing chamber; wherein:

[0014] The outer wall of the mixing section is arranged opposite to the outer wall of the heat exchange pipeline; and / or,

[0015] The outer wall of the diffusion part is arranged opposite to the outer wall of the heat exchange pipeline.

[0016] Furthermore, the ejector further comprises:

[0017] The contraction portion encloses a contraction cavity, the contraction cavity is arranged on a side of the mixing cavity away from the diffusion cavity and is connected to the mixing cavity, and the cross-sectional flow area of ​​the contraction cavity gradually decreases from the contraction cavity to the mixing cavity; the injection inlet is arranged on the contraction portion and is arranged toward the mixing cavity; the outer wall of the contraction portion is arranged opposite to the outer wall of the heat exchange pipeline; and / or,

[0018] The injection part is located in the contraction chamber, the injection part is connected to the injection inlet, and the nozzle of the injection part is arranged toward the mixing chamber.

[0019] Furthermore, the ejector also has a reflux cavity, one end of which forms a reflux hydrogen port connected to a reflux hydrogen source, and the other end of which is connected to a reflux inlet; wherein,

[0020] The heat exchange pipeline is spirally wound around the ejector along the extension direction of the ejector, and the reflux cavity is arranged opposite to the outer wall of the heat exchange pipeline; or, at least part of the heat exchange pipeline is an annular structure, and the annular structure is arranged around the reflux cavity.

[0021] Furthermore, the ejector device further comprises a heat exchange fin, which is arranged at the outer wall of the heat exchange pipeline and is arranged opposite to the outer wall of the connecting pipeline;

[0022] Wherein, the heat exchange fins are extended along the extension direction of the heat exchange channel, there are multiple heat exchange fins, and the multiple heat exchange fins are arranged at intervals along the circumferential direction of the heat exchange pipeline; or,

[0023] The heat exchange fins are arranged around the heat exchange pipeline, there are multiple heat exchange fins, and the multiple heat exchange fins are arranged at intervals along the extension direction of the heat exchange flow channel.

[0024] According to another aspect of the present invention, there is provided a hydrogen fuel cell system, comprising: the above-mentioned ejection device;

[0025] The fuel cell stack body, the hydrogen outlet of the ejector device is connected with the anode of the fuel cell stack body.

[0026] Furthermore, the hydrogen fuel cell system further comprises:

[0027] The cooling structure has a cooling channel for introducing a heat exchange medium, at least part of which is arranged in the fuel cell stack; the cooling channel is connected to the heat exchange channel of the ejector device.

[0028] Furthermore, the hydrogen fuel cell system further comprises:

[0029] A steam-water separator, the steam-water separator has a separation chamber, an inlet, a first outlet and a second outlet, the inlet, the first outlet and the second outlet are all connected to the separation chamber, the inlet is used to be connected to the anode of the fuel cell stack so that excess hydrogen in the anode can flow into the separation chamber; the first outlet is used to discharge liquid, and the second outlet is used to discharge mixed gas, which includes hydrogen and water vapor; the second outlet is used to be connected to the reflux hydrogen port of the ejector of the ejector device.

[0030] By applying the technical solution of the present invention, the temperature of hydrogen before entering the fuel cell stack can be effectively adjusted through heat exchange between the heat exchange pipeline and the connecting pipeline, so as to facilitate preheating of hydrogen, which helps to improve the overall operating performance and efficiency of the fuel cell system. Especially in a low temperature environment, the heat exchange medium can be heated by a preheating device (such as a PTC heater) and then circulated to the heat exchange pipeline, heating the hydrogen in the connecting pipeline, thereby increasing the overall temperature of the gas in the ejector, avoiding the condensation and freezing of water vapor contained in the gas in the ejector at low temperatures, and ensuring that the system can also operate stably under low temperature conditions. At the same time, the heat exchange pipeline is arranged at the outer wall of the ejector, and can exchange heat with the ejector as a whole, thereby helping to preheat the inside of the ejector and ensure the normal operation of the ejector. Preheating the connecting pipeline and the ejector by the heat exchange medium reduces the risk of water in the gas freezing in a narrow nozzle or flow channel, and avoids the problem of ejector performance degradation or blockage. The ejector is tightly integrated with the heat exchange pipeline and the connecting pipeline, reducing the need for additional equipment, thereby making the entire device structure more compact, which is conducive to the integration and miniaturization of the fuel cell system. Therefore, the technical problem of ice formation inside the ejector in the prior art can be solved through the technical solution of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0032] Figure 1 It shows a schematic structural diagram of an ejection device provided according to the first embodiment of the present invention;

[0033] Figure 2 A schematic structural diagram of a hydrogen fuel cell system provided according to a second embodiment of the present invention is shown.

[0034] The above drawings include the following reference numerals:

[0035] 1. ejector; 11. ejector inlet; 12. reflux inlet; 13. ejector; 14. reflux hydrogen inlet; 15. hydrogen outlet; 101. contraction chamber; 102. mixing chamber; 103. diffusion chamber;

[0036] 2. Heat exchange pipeline; 21. Heat exchange flow channel; 22. Medium inlet; 23. Medium outlet; 201. Heat exchange pipe section;

[0037] 3. Connecting pipeline; 31. Hydrogen inlet; 301. Connecting pipe section;

[0038] 4. Heat exchange fins;

[0039] 5. Fuel cell stack;

[0040] 6. Cooling structure; 61. Outflow path; 62. Inflow path; 63. Water pump; 64. First connecting path; 65. Second connecting path;

[0041] 7. Steam-water separator; 71. inlet; 72. first outlet; 73. second outlet;

[0042] 8. Ejection device;

[0043] 91. First pressure reducing valve; 92. Second pressure reducing valve; 93. Hydrogen source. DETAILED DESCRIPTION

[0044] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0045] like Figure 1 As shown, the first embodiment of the present invention provides an ejector device 8, which includes an ejector 1, a heat exchange pipeline 2 and a connecting pipeline 3. The heat exchange pipeline 2 is arranged at the outer wall of the ejector 1; the tube cavity of the heat exchange pipeline 2 is a heat exchange flow channel 21 for the circulation of heat exchange medium; the heat exchange pipeline 2 includes at least two heat exchange pipe sections 201, and two adjacent heat exchange pipe sections 201 are interconnected and arranged at intervals. One end of the connecting pipeline 3 is connected to the ejection inlet 11 of the ejector 1, and the other end is connected to the hydrogen source; the connecting pipeline 3 has a connecting pipe section 301, which is arranged at the outer wall of the ejector 1 and between two adjacent heat exchange pipe sections 201, so that the two adjacent heat exchange pipe sections 201 can exchange heat with the connecting pipe section 301.

[0046] By using the ejector device 8 provided in the first embodiment of the present invention, the temperature of hydrogen before entering the fuel cell stack can be effectively adjusted through the heat exchange between the heat exchange pipeline 2 and the connecting pipeline 3, so as to facilitate the preheating of hydrogen, which helps to improve the overall operating performance and efficiency of the fuel cell system. Especially in a low temperature environment, the heat exchange medium can be heated by a preheating device (such as a PTC heater) and then circulated to the heat exchange pipeline 2, heating the hydrogen in the connecting pipeline 3, thereby increasing the overall temperature of the gas in the ejector 1, avoiding the condensation and freezing of water vapor contained in the gas in the ejector 1 at low temperatures, and ensuring that the system can also operate stably under low temperature conditions. At the same time, the heat exchange pipeline 2 is arranged at the outer wall of the ejector 1, and can exchange heat with the ejector 1 as a whole, thereby helping to preheat the inside of the ejector 1 and ensure the normal operation of the ejector 1. Preheating the connecting pipeline 3 and the ejector 1 by the heat exchange medium reduces the risk of water in the gas freezing in a narrow nozzle or flow channel, and avoids the problem of performance degradation or blockage of the ejector 1. The ejector 1 is tightly integrated with the heat exchange pipe 2 and the connecting pipe 3, reducing the need for additional equipment, thereby making the entire device structure more compact, which is conducive to the integration and miniaturization of the fuel cell system. Therefore, the ejector device provided in this embodiment can solve the technical problem of ice formation inside the ejector in the prior art.

[0047] Specifically, when the hydrogen fuel cell system is operating normally, the heat exchange medium can be the circulating coolant of the fuel cell stack 5, so that the waste heat in the circulating coolant of the fuel cell stack 5 can be fully utilized to preheat the hydrogen, thereby improving the thermal energy utilization efficiency of the fuel cell system and reducing dependence on external heat sources.

[0048] Specifically, the connecting pipe 3 is spirally wound around the ejector 1 along the extension direction of the ejector 1, and the spiral section of the connecting pipe 3 forms a connecting pipe section 301. With such a structural setting, the spiral connecting pipe 3 is in close contact with the outer wall of the ejector 1, which improves the structural strength of the connecting pipe 3, reduces the risk of pipe deformation or damage under long-term operation, and enhances the long-term operation reliability of the system. The spiral design makes full use of the limited space around the ejector 1, making the entire device more compact, which is conducive to the integration and layout of the fuel cell system.

[0049] Specifically, there are multiple connecting pipe segments 301 , and the connecting pipeline 3 has multiple spiral segments connected in sequence, and each spiral segment forms a corresponding connecting pipe segment 301 .

[0050] In another embodiment, the connecting pipeline 3 includes at least two connecting pipe sections 301, each connecting pipe section 301 is an annular structure, two adjacent connecting pipe sections 301 are interconnected and arranged at intervals along the extension direction of the ejector 1, and at least two heat exchange pipe sections 201 and at least two connecting pipe sections 301 correspond to each other and are arranged alternately. With such a structural arrangement, the connecting pipe section 301 corresponds to the heat exchange pipe section 201 one by one and is arranged alternately, so that the heat exchange between the two is more compact and efficient, the thermal management capability of the entire device is enhanced, and the accuracy of hydrogen preheating and reflux hydrogen temperature control is improved. The connecting pipe section 301 with an annular structure and the design of alternating arrangement optimize the spatial layout, making the device more compact as a whole, which is conducive to the miniaturization and integration of the fuel cell system.

[0051] In another embodiment, the connecting pipe 3 further includes a connecting pipe section, and two adjacent connecting pipe sections 301 are connected to each other through the connecting pipe section.

[0052] In this embodiment, the heat exchange pipeline 2 is spirally wound on the ejector 1 along the extension direction of the ejector 1. With such a structural arrangement, the spiral winding increases the contact area between the heat exchange pipeline 2 and the outer wall of the ejector 1, so that the heat exchange medium can more fully preheat the ejector 1 and the hydrogen inside it, thereby improving the heat exchange efficiency. The spiral structure helps to evenly distribute the temperature along the length direction of the ejector 1, avoid local overheating or excessive temperature gradients, ensure that the hydrogen is at an appropriate temperature when entering the fuel cell stack, and is conducive to the stable operation of the system. The spiral layout is compact, which reduces the overall volume of the heat exchange device, and is conducive to the integration and miniaturization design of the fuel cell system. At the same time, this layout method also helps to achieve efficient heat exchange in a limited space.

[0053] Specifically, the heat exchange pipeline 2 has at least two spiral sections connected in sequence, and each spiral section forms a corresponding heat exchange pipe section 201.

[0054] In another embodiment, each heat exchange pipe segment 201 is an annular structure, and at least two heat exchange pipe segments 201 are arranged at intervals along the extension direction of the ejector 1 to form an annular structure, and at least part of the ejector 1 is inserted into the annular structure and arranged relative to the annular structure. With such a structural arrangement, the annular structure can ensure a more sufficient heat exchange between the heat exchange medium and the outer wall of the ejector 1, improve the uniformity of the heat exchange, and avoid the situation where the local temperature is too high or too low when the hydrogen gas flows. The heat exchange pipe segments 201 with an annular structure are arranged around the ejector 1, which not only realizes efficient heat exchange, but also makes the entire device compact, saves valuable space inside the system, and is conducive to the overall design optimization of the fuel cell system.

[0055] Specifically, each heat exchange pipe segment 201 is tilted, and the angle between the tilt direction of the heat exchange pipe segment 201 and the extension direction of the ejector 1 is α, 45°≤α≤90°. Such a structural setting is helpful to optimize the flow rate and distribution of the heat exchange medium in the heat exchange pipe segment 201, avoid possible turbulence or retention of the fluid, ensure the smoothness of the medium flow, and thus improve the transmission efficiency of heat energy.

[0056] Specifically, the ejector 1 includes a mixing part and a diffusion part which are interconnected, the mixing part encloses a mixing chamber 102, and the diffusion part encloses a diffusion chamber 103, the cross-sectional flow area of ​​the diffusion chamber 103 gradually increases along the direction from the mixing chamber 102 to the diffusion chamber 103, and the ejector 1 is also provided with a reflux inlet 12 which is connected to the reflux hydrogen source, and the reflux inlet 12 and the ejection inlet 11 are both connected to the mixing chamber 102; wherein, the outer wall of the mixing part is arranged relative to the outer wall of the heat exchange pipeline 2. With such a structural arrangement, the mixing chamber 102 provides space so that the new hydrogen and the reflux hydrogen can be mixed more fully, thereby optimizing the quality of the hydrogen entering the fuel cell stack 5 and improving the efficiency of the electrochemical reaction. The outer wall of the mixing part is arranged relative to the outer wall of the heat exchange pipeline 2, which can increase the contact area of ​​the heat exchange, improve the preheating speed, and ensure that the hydrogen can stably pass through the mixing chamber 102 in a low temperature environment to avoid ice blockage.

[0057] Specifically, the reflux hydrogen source is the excess hydrogen in the fuel cell stack 5 .

[0058] Specifically, the ejector 1 includes a mixing part and a diffusion part which are interconnected, the mixing part encloses a mixing chamber 102, and the diffusion part encloses a diffusion chamber 103, the cross-sectional flow area of ​​the diffusion chamber 103 gradually increases along the direction from the mixing chamber 102 to the diffusion chamber 103, and the ejector 1 is also provided with a reflux inlet 12 which is connected to the reflux hydrogen source, and the reflux inlet 12 and the ejection inlet 11 are both connected to the mixing chamber 102; wherein, the outer wall of the diffusion part is arranged relative to the outer wall of the heat exchange pipeline 2. With such a structural arrangement, the outer wall of the diffusion part is arranged relative to the outer wall of the heat exchange pipeline 2, which is conducive to achieving uniform temperature distribution in the diffusion chamber 103, avoiding local overheating or overcooling, and ensuring uniform conditions for the reaction of hydrogen and air in the fuel cell. The relative arrangement of the diffusion part and the heat exchange pipeline 2 can provide additional temperature protection for the sensitive area of ​​the ejector 1 (such as the connection between the mixing chamber 102 and the diffusion chamber 103), reducing the risk of possible performance degradation or damage in a low temperature environment.

[0059] Specifically, a side of the diffusion chamber 103 away from the mixing chamber 102 has a hydrogen outlet 15 , and the hydrogen outlet 15 is connected to the anode of the fuel cell stack 5 .

[0060] Specifically, the ejector 1 also includes a contraction portion, which encloses a contraction chamber 101. The contraction chamber 101 is arranged on the side of the mixing chamber 102 away from the diffusion chamber 103 and is connected to the mixing chamber 102. The cross-sectional flow area of ​​the contraction chamber 101 gradually decreases along the direction from the contraction chamber 101 to the mixing chamber 102; the ejection inlet 11 is arranged on the contraction portion and is arranged toward the mixing chamber 102; the outer wall of the contraction portion is arranged opposite to the outer wall of the heat exchange pipeline 2. With such a structural arrangement, the cross-sectional area of ​​the contraction chamber 101 is gradually reduced, which can significantly increase the flow rate of hydrogen and help enhance the ejection capacity of the ejector. The outer wall of the contraction portion is arranged opposite to the outer wall of the heat exchange pipeline 2, so that the temperature in the contraction chamber can be maintained within a certain range, especially for fuel cell systems under low-temperature startup and operation conditions, the preheating effect can be achieved faster to avoid ice problems.

[0061] Specifically, the ejector 1 further includes an ejector 13, which is located in the contraction chamber 101, connected to the ejection inlet 11, and a nozzle of the ejector 13 is arranged toward the mixing chamber 102. With such a structural arrangement, the design of the ejector 13 ensures that hydrogen can enter the mixing chamber 102 at a predetermined speed and direction, thereby avoiding fluid turbulence and improving ejection efficiency.

[0062] In this embodiment, the ejector 1 also has a reflux cavity, one end of which forms a reflux hydrogen port 14 connected to the reflux hydrogen source, and the other end is connected to the reflux inlet 12; wherein the heat exchange pipeline 2 is spirally wound on the ejector 1 along the extension direction of the ejector 1, and the reflux cavity is arranged opposite to the outer wall of the heat exchange pipeline 2; or, at least part of the heat exchange pipeline 2 is an annular structure, and the annular structure is arranged around the reflux cavity. With such a structural arrangement, the reflux hydrogen can be effectively heated by the heat radiation of the heat exchange pipeline 2, and the water vapor in the reflux hydrogen can be prevented from being liquefied and frozen when it is cooled in a low-temperature environment, thereby ensuring the normal operation of the ejector 1.

[0063] Specifically, the ejector device 8 further includes heat exchange fins 4, which are arranged at the outer wall of the heat exchange pipeline 2 and are arranged opposite to the outer wall of the connecting pipeline 3. With such a structural arrangement, the arrangement of the heat exchange fins 4 increases the surface area of ​​heat exchange, improves the heat exchange efficiency, and enables the hydrogen in the connecting pipeline 3 to be preheated more quickly and evenly. The fin structure can also enhance the structural strength of the heat exchange pipeline 2, reduce pipeline deformation or damage caused by thermal expansion and contraction, and extend the service life of the equipment.

[0064] Specifically, the heat exchange fins 4 are extended along the extension direction of the heat exchange flow channel 21, and there are multiple heat exchange fins 4, and the multiple heat exchange fins 4 are arranged at intervals along the circumference of the heat exchange pipeline 2. In this way, the heat exchange fins 4 arranged at intervals help to evenly distribute the temperature in the circumference of the heat exchange pipeline 2, avoid local overheating, ensure that the hydrogen temperature is stable and evenly distributed, which is conducive to the uniform occurrence of electrochemical reactions inside the fuel cell, and improves the overall performance and reliability of the system.

[0065] Specifically, the heat exchange fins 4 are arranged around the heat exchange pipeline 2, and there are multiple heat exchange fins 4, and the multiple heat exchange fins 4 are arranged at intervals along the extension direction of the heat exchange flow channel 21. In this way, the heat exchange fins 4 are arranged around the heat exchange pipeline 2, which can achieve all-round heat exchange, ensure that the hydrogen can be fully preheated when passing through the heat exchange pipeline 2, avoid the problem of uneven hydrogen temperature control, and improve the stability and environmental adaptability of the system.

[0066] like Figure 1 As shown, the ejection device 8 is connected to the external hydrogen source 93 through the hydrogen inlet 31. The new hydrogen enters the annular flow channel (equivalent to the tube cavity of the connecting pipeline 3) through the hydrogen inlet 31, and enters the injection part 13 through the annular flow channel. The new hydrogen is ejected from the nozzle of the injection part 13, and produces an ejection effect in the mixing chamber 102, mixing the reflux hydrogen coming in from the reflux hydrogen port 14, entering the diffusion chamber 103, and finally going out through the hydrogen outlet 15 and entering the fuel cell stack 5.

[0067] like Figure 2 As shown, the second embodiment of the present invention provides a hydrogen fuel cell system, which includes the ejector device 8 and the fuel cell stack 5 in the first embodiment, and the hydrogen outlet 15 of the ejector device 8 is connected to the anode of the fuel cell stack 5.

[0068] The hydrogen fuel cell system provided by the second embodiment of the present invention can effectively adjust the temperature of hydrogen before entering the fuel cell stack through the heat exchange between the heat exchange pipeline 2 and the connecting pipeline 3, so as to facilitate the preheating of hydrogen, which helps to improve the overall operating performance and efficiency of the fuel cell system. Especially in a low temperature environment, the heat exchange medium can be heated by a preheating device (such as a PTC heater) and then circulated to the heat exchange pipeline 2, heating the hydrogen in the connecting pipeline 3, thereby increasing the overall temperature of the gas in the ejector 1, avoiding the condensation and freezing of water vapor contained in the gas in the ejector 1 at low temperatures, and ensuring that the system can also operate stably under low temperature conditions. At the same time, the heat exchange pipeline 2 is arranged at the outer wall of the ejector 1, and can exchange heat with the ejector 1 as a whole, thereby helping to preheat the inside of the ejector 1 and ensure the normal operation of the ejector 1. Preheating the connecting pipeline 3 and the ejector 1 by the heat exchange medium reduces the risk of water in the gas freezing in a narrow nozzle or flow channel, and avoids the problem of performance degradation or blockage of the ejector 1. The ejector 1 is tightly integrated with the heat exchange pipe 2 and the connecting pipe 3, reducing the need for additional equipment, thereby making the entire device structure more compact, which is conducive to the integration and miniaturization of the fuel cell system. Therefore, the hydrogen fuel cell system provided in this embodiment can solve the technical problem of ice formation inside the ejector in the prior art.

[0069] Specifically, the hydrogen fuel cell system also includes a cooling structure 6, which has a cooling channel for passing a heat exchange medium, at least part of which is arranged in the fuel cell stack 5; the cooling channel is connected to the heat exchange channel 21 of the ejector 8. With such a structural arrangement, the cooling channel of the cooling structure 6 is integrated with the inside of the fuel cell stack 5, which can directly and effectively cool the fuel cell stack, ensuring that the stack avoids overheating when operating at a high power density, thereby improving the thermal management efficiency and operating stability of the system. By connecting the cooling channel with the heat exchange channel 21 of the ejector 8, the heat energy recovered from the fuel cell stack 5 can be used to preheat the hydrogen, thereby realizing the internal recycling of heat energy and improving energy utilization efficiency.

[0070] Specifically, the cooling flow channel includes an outflow channel 61 and an inflow channel 62. The outflow channel 61 is used to guide the hot coolant circulated from the inside of the fuel cell stack 5 to the outside of the cooling structure 6. During operation, the fuel cell stack 5 will generate a large amount of heat, which needs to be removed by the coolant. The outflow channel 61 is directly connected to the cooling channel in the fuel cell stack 5 to ensure that the hot coolant can be effectively discharged for the next step of cooling or heat recovery. The inflow channel 62 is used to reintroduce the cooled or preheated coolant into the fuel cell stack 5. In the cooling system, the coolant is externally cooled or preheated and then circulated back to the fuel cell stack 5 through the inflow channel 62 to cool or heat the stack to meet the temperature requirements of the system operation.

[0071] Specifically, the cooling structure 6 includes a water pump 63, which is arranged on the cooling flow channel to provide power for the circulation of the coolant. The coolant is pressurized by the water pump 63 and is pushed to circulate in the cooling structure 6 to ensure that the coolant flows smoothly between the outflow flow path 61 and the inflow flow path 62.

[0072] Specifically, the cooling structure 6 further includes a first connecting flow path 64 and a second connecting flow path 65. The medium inlet 22 of the heat exchange pipeline 2 is connected to the stack inlet flow path 62 through the first connecting flow path 64, and the medium outlet 23 of the heat exchange pipeline 2 is connected to the stack outlet flow path 61 through the second connecting flow path 65. In this way, by connecting the cooling flow path with the heat exchange flow path 21 of the ejector device 8, the heat energy recovered from the fuel cell stack 5 can be used to preheat the hydrogen, thereby realizing the internal recycling of heat energy and improving the energy utilization efficiency.

[0073] Specifically, the hydrogen fuel cell system further includes a steam-water separator 7, which has a separation chamber, an inlet 71, a first outlet 72 and a second outlet 73. The inlet 71, the first outlet 72 and the second outlet 73 are all connected to the separation chamber. The inlet 71 is used to be connected to the anode of the fuel cell stack 5 so that the excess hydrogen in the anode flows into the separation chamber; the first outlet 72 is used to discharge liquid, and the second outlet 73 is used to discharge mixed gas, which includes hydrogen and water vapor; the second outlet 73 is used to be connected to the reflux hydrogen port 14 of the ejector 1 of the ejector device 8. With such a structural arrangement, the steam-water separator 7 can separate the excess hydrogen from the water vapor in the anode of the fuel cell stack 5, and guide the mixed gas (hydrogen and water vapor) to the reflux hydrogen port 14 of the ejector device 8 through the second outlet 73, thereby reducing the water content in the reflux hydrogen, reducing the possibility of water vapor condensing and freezing in a low temperature environment and blocking the ejector 1, and ensuring the unimpeded circulation of hydrogen.

[0074] Specifically, the hydrogen fuel cell system also includes a first pressure reducing valve 91, a second pressure reducing valve 92 and a hydrogen source 93. The hydrogen source 93 can be a high-pressure hydrogen cylinder, a hydrogen production device or other forms of hydrogen supply units, which is responsible for providing the hydrogen required by the fuel cell system. The hydrogen source 93 is connected to the first pressure reducing valve 91 through a pipeline. The first pressure reducing valve 91 is arranged in the pipeline from the hydrogen source 93 to the second pressure reducing valve 92. Its function is to preliminarily reduce the pressure of the high-pressure hydrogen provided by the hydrogen source 93 to achieve a relatively stable intermediate pressure suitable for secondary pressure reduction. The first pressure reducing valve 91 is usually installed in a position close to the hydrogen source 93 in the fuel cell system to reduce the transmission distance of the high-pressure hydrogen in the pipeline and reduce the safety risk of the system. The second pressure reducing valve 92 is located after the first pressure reducing valve 91, closer to the position of the fuel cell stack 5. It is responsible for further reducing the pressure of the hydrogen output by the first pressure reducing valve 91 to a pressure suitable for the operation of the fuel cell stack 5. The setting of the second pressure reducing valve 92 ensures that the fuel cell stack 5 can obtain a stable and suitable pressure hydrogen supply, avoiding the performance and life of the stack being affected by excessive or low pressure. The second pressure reducing valve 92 is connected to the pipeline between the first pressure reducing valve 91 and the ejector device 8 .

[0075] like Figure 1 and Figure 2As shown, hydrogen passes through the first pressure reducing valve 91 and the second pressure reducing valve 92 from the hydrogen source 93, enters the hydrogen inlet 31 of the ejector 8, and enters the connecting pipeline 3 for heat exchange. After the heat exchange, the hydrogen is increased in flow rate through the nozzle (equivalent to the injection part 13) and then mixed with the reflux hydrogen, and enters the anode chamber of the hydrogen fuel cell system to undergo an electrochemical reaction. After the reaction, the mixed gas enters the steam-water separator 7 for gas-liquid separation, and finally enters the reflux chamber for reflux circulation. The reflux hydrogen contains a certain amount of water vapor, and the ejector 8 of this scheme has a dual function, which can preheat the new hydrogen and also keep the reflux hydrogen warm to prevent ice from forming in the narrow nozzle or in the mixing chamber 102 to block the airway in a low temperature environment. Secondly, it can preheat the incoming hydrogen, thereby improving the environmental performance of the equipment. The coolant of the fuel cell system can be heated by a PTC (positive temperature coefficient) heater at the initial stage, and circulated by a water pump 63. After the coolant is preheated, it enters the heat exchange channel 21 through the medium inlet 22, exchanges heat with the new hydrogen through the heat exchange fins 4, and preheats the new hydrogen. At the same time, the outer wall of the heat exchange pipeline 2 and the outer wall of the ejector 1 exchange heat with each other, which can preheat the ejector 1 and preheat the inside of the ejector 1 to prevent the ejector 1 from freezing and hindering normal operation. Finally, after a series of heat exchanges, the coolant enters the cooling structure 6 from the medium outlet 23 for circulation. After the hydrogen fuel cell system is started, there is no need for PTC heater heating. The waste heat of the fuel cell system can both preheat the ejector 1 and increase the temperature of the new hydrogen. Increasing the temperature of the reaction gas can improve the operating performance of hydrogen in the system, while also improving the utilization rate of the system waste heat, and overall improving the operating performance and efficiency of the system. Secondly, the ejection reflux and hydrogen preheating are highly integrated, with a small size and large functions, which is conducive to the promotion of integrated application of fuel cell systems.

[0076] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0077] 1. Adaptability to low temperature environment: Through the integrated heat exchange pipeline and connecting pipeline, hydrogen preheating and heat preservation of ejector reflux hydrogen are realized, which effectively prevents ice blockage inside the ejector in low temperature environment and ensures the normal operation of the system, especially reliable operation in extremely cold environment.

[0078] 2. Improved system stability and efficiency: The preheating function of the system cooling circuit is used to increase the temperature of the hydrogen entering the reactor, which is conducive to the electrochemical reaction and improves the system efficiency. When the system is operating normally, preheating through the residual heat of the cooling circuit not only increases the temperature of the hydrogen, but also improves the operating effect of the ejector, effectively improving the operating stability and thermal efficiency of the system.

[0079] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0080] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the application. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0081] In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0082] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0083] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An ejection device, characterized in that: include: Ejector (1); A heat exchange pipeline (2) is arranged on the outer wall of the ejector (1); the lumen of the heat exchange pipeline (2) is a heat exchange channel (21) for circulating a heat exchange medium; the heat exchange pipeline (2) comprises at least two heat exchange pipe sections (201), and two adjacent heat exchange pipe sections (201) are interconnected and spaced apart; A connecting pipe (3), one end of the connecting pipe (3) being connected to the ejection inlet (11) of the ejector (1), and the other end being connected to the hydrogen source; the connecting pipe (3) having a connecting pipe section (301), the connecting pipe section (301) being arranged on the outer wall of the ejector (1) and being located between two adjacent heat exchange pipe sections (201), so that the two adjacent heat exchange pipe sections (201) can both perform heat exchange with the connecting pipe section (301).

2. The ejection device according to claim 1, characterized in that: The connecting pipeline (3) is spirally wound around the ejector (1) along the extension direction of the ejector (1), and the spiral section of the connecting pipeline (3) forms the connecting pipeline section (301); or, The connecting pipeline (3) comprises at least two connecting pipe sections (301), each of the connecting pipe sections (301) is an annular structure, two adjacent connecting pipe sections (301) are connected to each other and are arranged at intervals along the extension direction of the ejector (1), and at least two heat exchange pipe sections (201) and at least two connecting pipe sections (301) correspond to each other one by one and are arranged alternately.

3. The ejection device according to claim 1, characterized in that: The heat exchange pipeline (2) is spirally wound around the ejector (1) along the extension direction of the ejector (1); or, Each of the heat exchange pipe sections (201) is an annular structure, and at least two of the heat exchange pipe sections (201) are arranged at intervals along the extension direction of the ejector (1) to form an annular structure, and at least a portion of the ejector (1) is inserted into the annular structure and is arranged opposite to the annular structure.

4. The ejection device according to claim 1, characterized in that: The ejector (1) comprises a mixing portion and a diffusion portion which are interconnected, the mixing portion enclosing a mixing chamber (102), the diffusion portion enclosing a diffusion chamber (103), the cross-sectional flow area of ​​the diffusion chamber (103) gradually increasing along the direction from the mixing chamber (102) to the diffusion chamber (103), the ejector (1) is further provided with a reflux inlet (12) which is connected to a reflux hydrogen source, the reflux inlet (12) and the ejector inlet (11) are both connected to the mixing chamber (102); wherein: The outer wall of the mixing portion is arranged opposite to the outer wall of the heat exchange pipeline (2); and / or, The outer wall of the diffusion portion is arranged opposite to the outer wall of the heat exchange pipeline (2).

5. The ejection device according to claim 4, characterized in that: The ejector (1) further comprises: a contraction portion, the contraction portion enclosing a contraction cavity (101), the contraction cavity (101) being arranged on a side of the mixing cavity (102) away from the diffusion cavity (103) and being in communication with the mixing cavity (102), the cross-sectional flow area of ​​the contraction cavity (101) gradually decreasing along a direction from the contraction cavity (101) to the mixing cavity (102); the injection inlet (11) being arranged on the contraction portion and facing the mixing cavity (102); the outer wall of the contraction portion being arranged opposite to the outer wall of the heat exchange pipeline (2); and / or, An injection portion (13), the injection portion (13) is located in the contraction chamber (101), the injection portion (13) is connected to the injection inlet (11), and the nozzle of the injection portion (13) is arranged toward the mixing chamber (102).

6. The ejection device according to claim 4, characterized in that: The ejector (1) further comprises a reflux chamber, one end of which forms a reflux hydrogen port (14) connected to the reflux hydrogen source, and the other end of which is connected to the reflux inlet (12); wherein: The heat exchange pipeline (2) is spirally wound around the ejector (1) along the extension direction of the ejector (1), and the reflux chamber is arranged opposite to the outer wall of the heat exchange pipeline (2); or, at least a portion of the heat exchange pipeline (2) is an annular structure, and the annular structure is arranged around the reflux chamber.

7. The ejection device according to any one of claims 1 to 6, characterized in that: The ejection device further comprises a heat exchange fin (4), wherein the heat exchange fin (4) is arranged on the outer wall of the heat exchange pipeline (2) and is arranged opposite to the outer wall of the connecting pipeline (3); The heat exchange fins (4) are extended along the extension direction of the heat exchange channel (21), and there are a plurality of heat exchange fins (4), and the plurality of heat exchange fins (4) are arranged at intervals along the circumference of the heat exchange pipeline (2); or, the heat exchange fins (4) are arranged around the heat exchange pipeline (2), and there are a plurality of heat exchange fins (4), and the plurality of heat exchange fins (4) are arranged at intervals along the extension direction of the heat exchange channel (21).

8. A hydrogen fuel cell system, characterized in that: include: The ejection device according to any one of claims 1 to 7; A fuel cell stack (5), wherein the hydrogen outlet (15) of the ejector device is connected to the anode of the fuel cell stack (5).

9. The hydrogen fuel cell system according to claim 8, characterized in that: The hydrogen fuel cell system further comprises: A cooling structure (6), wherein the cooling structure (6) has a cooling channel for passing a heat exchange medium, wherein at least a portion of the cooling channel is disposed within the fuel cell stack (5); and the cooling channel is connected to a heat exchange channel (21) of the ejector device.

10. The hydrogen fuel cell system according to claim 8, characterized in that: The hydrogen fuel cell system further comprises: A steam-water separator (7), the steam-water separator (7) having a separation chamber, an inlet (71), a first outlet (72) and a second outlet (73), the inlet (71), the first outlet (72) and the second outlet (73) are all connected to the separation chamber, the inlet (71) is used to be connected to the anode of the fuel cell stack (5) so that excess hydrogen in the anode flows into the separation chamber; the first outlet (72) is used to discharge liquid, the second outlet (73) is used to discharge mixed gas, and the mixed gas includes hydrogen and water vapor; the second outlet (73) is used to be connected to the reflux hydrogen port (14) of the ejector (1) of the ejector device.

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