Airflow distribution device and module

Abstract

The invention discloses an airflow distribution device and a module, the airflow distribution device comprises a main body part and an isolation device, the main body part is provided with a waste gas discharge structure and a first side surface and a second side surface which are oppositely arranged, the first side surface is provided with a first supply area, and the second side surface is provided with a second supply area; an isolating device is arranged between the first supply area and the second supply area to separate the first supply area from the second supply area, the first supply area is provided with a first fuel supply structure, the two ends of the first fuel supply structure are communicated with a first fuel inlet of the first electric pile and a fuel source respectively, and the second supply area is provided with a second fuel supply structure; and two ends of the second fuel supply structure are respectively communicated with a second fuel inlet of the second electric pile and the fuel source. According to the invention, the influence of processing errors generated in the manufacturing process on gas distribution can be effectively reduced, the purity and the stability of fuel supply are ensured, and the consistency and the reliability among the electric piles can be maintained.

Description

Technical Field

[0001] The present invention relates to the field of solid oxide fuel cells, and in particular to an air flow distribution device and a module. Background Art

[0002] Solid oxide fuel cells (SOFCs) are efficient and environmentally friendly electrochemical devices that can directly convert the chemical energy stored in fuel and oxidant into electrical energy. Since the 1940s, fuel cell technology has undergone four generations of development. Among them, solid oxide fuel cells (SOFCs), as the third generation of fuel cells, stand out for their high power generation efficiency, strong fuel adaptability, and high-temperature waste heat recovery. The core of SOFC lies in the stable operation of its stack units. In order to reduce the temperature gradient between stack units and prevent damage caused by excessive fuel utilization in some stacks, the amount of gas supplied to each stack unit needs to be kept as consistent as possible.

[0003] Currently, gas distribution within each cell stack typically relies on a carefully designed flow channel system that is tightly integrated with the stack to ensure uniform gas distribution to each cell. However, in existing technology, due to the close correlation between the machining errors between the distribution channels and the stack, defective stacks within certain tolerance limits cannot achieve the expected gas distribution indicators. This not only affects the performance of the entire module but can also shorten its service life. Summary of the Invention

[0004] The purpose of the present invention is to provide an air flow distribution device and module that can effectively reduce the impact of processing errors caused during the manufacturing process on gas distribution, ensure the purity and stability of fuel supply, and help maintain the consistency and reliability of the performance of each fuel cell stack.

[0005] In order to achieve the above-mentioned objectives, the present invention provides an airflow distribution device for distributing airflow between a first fuel cell stack and a second fuel cell stack that are stacked, comprising a main body and an isolation device, wherein the main body has an exhaust gas discharge structure and a first side surface and a second side surface that are oppositely arranged, and the exhaust gas discharge structure is respectively connected to the first fuel outlet of the first fuel cell stack and the second fuel outlet of the second fuel cell stack, the first side surface is provided with a first supply area, and the second side surface is provided with a second supply area, and the isolation device is provided between the first supply area and the second supply area to separate the first supply area from the second supply area, the first supply area has a first fuel supply structure, and the two ends of the first fuel supply structure are respectively connected to the first fuel inlet and the fuel source of the first fuel stack, and the second supply area has a second fuel supply structure, and the two ends of the second fuel supply structure are respectively connected to the second fuel inlet and the fuel source of the second fuel stack.

[0006] Furthermore, the first fuel supply structure includes a first fuel channel and a first fuel chamber, the first fuel chamber is arranged corresponding to the first fuel inlet, and the first fuel chamber is externally connected to the fuel source through the first fuel channel;

[0007] The second fuel supply structure includes a second fuel channel and a second fuel chamber. The second fuel chamber is arranged corresponding to the second fuel inlet. The second fuel chamber is externally connected to the fuel source through the second fuel channel.

[0008] Furthermore, a difference in pressure loss between the first fuel channel and the second fuel channel does not exceed 10%.

[0009] Furthermore, the pressure loss of the first fuel channel is greater than the pressure loss between the first fuel outlet and the first fuel inlet, and the pressure loss of the second fuel channel is greater than the pressure loss between the second fuel outlet and the second fuel inlet.

[0010] Furthermore, the first fuel channel includes a first inlet section and a first outlet section, the first outlet section is in communication with the first fuel chamber, the first inlet section is externally connected to the fuel source, and the inner diameter of the first inlet section is larger than the inner diameter of the first outlet section;

[0011] The second fuel channel includes a second inlet section and a second outlet section. The second outlet section is communicated with the second fuel chamber. The second inlet section is externally connected to the fuel source. The inner diameter of the second inlet section is larger than the inner diameter of the second outlet section.

[0012] Furthermore, the first fuel channel is partially exposed outside the first fuel chamber and externally connected to the fuel source, and the tail end of the first outlet section is located inside the first fuel chamber;

[0013] The second fuel channel is partially exposed outside the second fuel chamber and connected to the fuel source, and the tail end of the second outlet section is located inside the second fuel chamber.

[0014] Furthermore, the system further comprises a plurality of precision tubes, wherein the first fuel channel is provided with the precision tubes, and one end of the precision tube facing away from the first fuel chamber is connected to the fuel source, and the pressure loss of the precision tubes is greater than the pressure loss between the first fuel outlet and the first fuel inlet; and / or,

[0015] The second fuel channel is provided with the precision tube, and one end of the precision tube away from the second fuel chamber is connected to the fuel source, and the pressure loss of the precision tube is greater than the pressure loss between the second fuel outlet and the second fuel inlet.

[0016] Furthermore, the precision tube includes a third inlet section and a third outlet section, the first fuel chamber and / or the second fuel chamber is connected to the corresponding third outlet section, the third inlet section is externally connected to the fuel source, and the inner diameter of the third inlet section is larger than the inner diameter of the third outlet section.

[0017] Furthermore, the tail end of the third outlet section is located inside the first fuel chamber or the second fuel chamber;

[0018] The length of the precision tube is greater than or equal to the first fuel channel and less than the sum of the lengths of the first fuel channel and the first fuel chamber; and / or the length of the precision tube is greater than or equal to the length of the second fuel channel and less than the sum of the lengths of the second fuel channel and the second fuel chamber.

[0019] The present invention also provides a module, comprising a first fuel cell stack, a second fuel cell stack and the air flow distribution device as described above, wherein the first fuel cell stack and the second fuel cell stack are stacked, and the air flow distribution device is located between the first fuel cell stack and the second fuel cell stack, the two ends of the first fuel supply structure are respectively connected to the first fuel inlet and the fuel source of the first fuel cell stack, the two ends of the second fuel supply structure are respectively connected to the second fuel inlet and the fuel source of the second fuel cell stack, and the exhaust gas discharge structure is respectively connected to the first fuel outlet of the first fuel stack and the second fuel outlet of the second fuel stack.

[0020] Compared with the prior art, the air flow distribution device and module according to the embodiment of the present invention have the following advantages:

[0021] The embodiment of the present invention sets a first supply area and a second supply area, and can supply fuel to the first fuel cell stack and the second fuel cell stack separately, thereby ensuring that the first fuel cell stack and the second fuel cell stack can obtain a preset amount of fuel, improving overall efficiency, and preventing direct interaction of fuel between the first supply area and the second supply area by setting an isolation device between the first supply area and the second supply area, thereby preventing uneven airflow entering the first fuel cell stack and the second fuel cell stack, and can effectively reduce the impact of processing errors generated in the manufacturing process on gas distribution, ensure the purity and stability of the fuel supply, and help maintain the consistency and reliability of the first fuel cell stack and the second fuel cell stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the structure of the module provided by the embodiment of the present invention;

[0023] Figure 2 is a structural schematic diagram of an air flow distribution device provided by an embodiment of the present invention;

[0024] Figure 3is a cross-sectional view of an air flow distribution device provided by an embodiment of the present invention;

[0025] Figure 4 1 is a schematic structural diagram of a precision tube provided by an embodiment of the present invention;

[0026] In the figure, 1. air flow distribution device; 11. main body; 111. exhaust gas discharge structure; 1111. exhaust gas through hole; 1112. exhaust gas channel; 112. first side; 113. second side; 12. isolation device; 13. first supply area; 131. first fuel supply structure; 1311. first fuel channel; 1312. first fuel chamber; 14. second supply area; 141. second fuel supply structure; 1411. second fuel channel; 1412. second fuel chamber; 15. precision tube; 151. inlet section; 152. outlet section; 2. first fuel stack; 3. second fuel stack; 31. second fuel outlet; 32. second fuel inlet. DETAILED DESCRIPTION

[0027] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0028] like Figures 1 to 3 As shown, the present invention provides a module, including an air flow distribution device 1, a first fuel cell stack 2 and a second fuel cell stack 3, the first fuel cell stack 2 and the second fuel cell stack 3 are stacked, and the air flow distribution device 1 is located between the first fuel cell stack 2 and the second fuel cell stack 3, and is used for air flow distribution between the stacked first fuel cell stack 2 and the second fuel cell stack 3, the air flow distribution device 1 includes a main body 11 and an isolation device 12, the main body 11 has an exhaust gas discharge structure 111 and a first side surface 112 and a second side surface 113 arranged opposite to each other, the exhaust gas discharge structure 111 is respectively connected to the first fuel outlet (not shown in the figure) of the first fuel cell stack 2 and the second fuel outlet 31 of the second fuel cell stack 3, so as to discharge the exhaust gas generated after the reaction, prevent the accumulation of exhaust gas from damaging the first fuel cell stack 2 and the second fuel cell stack 3, and also facilitate subsequent treatment or utilization of resources such as waste heat in these exhaust gases.

[0029] The first side 112 is provided with a first supply area 13, and the second side 113 is provided with a second supply area 14. An isolation device 12 is provided between the first supply area 13 and the second supply area 14 to separate the first supply area 13 from the second supply area 14. The two ends of the first supply area 13 are respectively connected to the first fuel inlet (not shown in the figure) and the fuel source of the first fuel stack 2, and the two ends of the second supply area 14 are respectively connected to the second fuel inlet 32 ​​and the fuel source of the second fuel stack 3, to ensure that the fuel can smoothly enter the first fuel stack 2 and the second fuel stack 3 for reaction. The two independent supply paths ensure that the first fuel stack 2 and the second fuel stack 3 have a stable and sufficient fuel supply to maintain continuous and efficient operation.

[0030] In this embodiment, the first fuel cell stack 2 and the second fuel cell stack 3 are arranged vertically together, and an airflow distribution device 1 is provided between the first fuel cell stack 2 and the second fuel cell stack 3 to adjust and optimize the airflow distribution between the adjacent first fuel cell stack 2 and the second fuel cell stack 3, ensuring that the first fuel cell stack 2 and the second fuel cell stack 3 can obtain a uniform and appropriate amount of fuel gas, thereby avoiding performance degradation or damage due to uneven distribution of fuel gas. It can be understood that by connecting multiple fuel cells in parallel and providing an airflow distribution device 1 between two adjacent fuel cells, a uniform distribution of fuel intake for each fuel cell stack within a large SOFC module system can be achieved, while decoupling the fuel gas distribution of each fuel cell stack within the module from the processing errors of the fuel cell stack itself.

[0031] Specifically, the first supply area 13 serves as a delivery area for supplying fuel to the first fuel cell stack 2 located above, providing fuel to the first fuel cell stack 2 so that the first fuel cell stack 2 generates chemical reaction and generates electricity. The first supply area 13 has a first fuel supply structure 131. The first fuel cell stack 2 is provided with a first fuel inlet at the bottom. The two ends of the first fuel supply structure 131 are respectively connected to the first fuel inlet and the fuel source of the first fuel cell stack 2. The second supply area 14 serves as a delivery area for supplying fuel to the second fuel cell stack 3 located below, providing fuel to the second fuel cell stack 3 so that the second fuel cell stack 3 generates chemical reaction and generates electricity. The second supply area 14 has a second fuel supply structure 141. The top of the second fuel cell stack 3 is provided with a second fuel inlet 32. The two ends of the second fuel supply structure 141 are respectively connected to the second fuel inlet 32 ​​and the fuel source of the second fuel cell stack 3.

[0032] It can be understood that in the airflow distribution device 1, the first supply area 13, the isolation device 12 and the second supply area 14 are arranged in sequence from top to bottom, and the isolation device 12 can isolate the two airflows of the first supply area 13 and the second supply area 14 to prevent the airflows of the first supply area 13 and the second supply area 14 from mixing. According to this structure, the amount of fuel in the first battery stack 2 and the second battery stack 3 can be controlled by controlling the airflow distribution of the first supply area 13 and the second supply area 14, thereby avoiding damage to the first battery stack 2 and the second battery stack 3 due to uneven fuel distribution. It should be noted that the isolation device 12 of this embodiment can be an independent component welded to the main body 11, or it can be integrally formed with the main body 11, and is not particularly limited here.

[0033] Based on the above structure, this embodiment sets the first supply area 13 and the second supply area 14, and can separately supply fuel to the first fuel cell stack 2 and the second fuel cell stack 3, thereby ensuring that the first fuel cell stack 2 and the second fuel cell stack 3 can both obtain the preset fuel amount, improving the overall efficiency, and preventing direct interaction of fuel between the first supply area 13 and the second supply area 14 by setting an isolation device 12 between the first supply area 13 and the second supply area 14, so as to prevent uneven airflow entering the first fuel cell stack 2 and the second fuel cell stack 3, and can effectively reduce the impact of processing errors generated in the manufacturing process on the gas distribution, thereby ensuring the purity and stability of the fuel supply, and helping to maintain the consistency and reliability between the first fuel cell stack 2 and the second fuel cell stack 3.

[0034] Furthermore, the exhaust gas discharge structure 111 includes an exhaust gas through hole 1111 and an exhaust gas channel 1112 . The exhaust gas through hole 1111 is connected to the first fuel outlet and the second fuel outlet 31 , respectively, and the exhaust gas through hole 1111 is in communication with the exhaust gas channel 1112 .

[0035] In this embodiment, a first fuel outlet is provided at the bottom of the first fuel stack 2, and a second fuel outlet 31 is provided at the top of the second fuel stack 3. The first fuel outlet and the second fuel outlet 31 are symmetrically designed; the first fuel outlet is used to discharge the exhaust gas of the first fuel stack 2, and the second fuel outlet 31 is used to discharge the exhaust gas of the second fuel stack 3. The exhaust gas of the first fuel stack 2 and the second fuel stack 3 are merged through the exhaust gas through hole 1111 and discharged together through the exhaust gas channel 1112. By uniformly outputting the exhaust gas from the first fuel outlet of the first fuel stack 2 and the second fuel outlet 31 of the second fuel stack 3, the pressure at the first fuel outlet 31 can be made consistent, the back pressure of the first fuel stack 2 and the second fuel stack 3 can be kept consistent, and the performance and distribution differences between the first fuel stack 2 and the second fuel stack 3 can be avoided.

[0036] It should be noted that the exhaust gas channel 1112 of this embodiment is externally connected to an exhaust gas pipe and an exhaust gas collecting device.

[0037] Furthermore, the first fuel supply structure 131 includes a first fuel channel 1311 and a first fuel chamber 1312. The first fuel channel 1311 serves as a path for transmitting fuel from an external fuel source to the first fuel chamber 1312. The first fuel chamber 1312 is connected to the fuel source through the first fuel channel 1311, and the first fuel chamber 1312 is correspondingly arranged to the first fuel inlet, so that the fuel is distributed to the first fuel stack 2 through the first fuel chamber 1312; the second fuel supply structure 141 includes a second fuel channel 1411 and a second fuel chamber 1412. The second fuel channel 1411 serves as a fuel supply path for the second fuel stack 3. The second fuel chamber 1412 is connected to the fuel source through the second fuel channel 1411, and the second fuel chamber 1412 is correspondingly arranged to the second fuel inlet 32, so that the fuel is distributed to the second fuel stack 3 through the second fuel chamber 1412.

[0038] The first fuel channel 1311 and the second fuel channel 1411 of this embodiment are used to provide a buffer path to slow down the speed at which the gas reaches the first fuel inlet and the second fuel inlet 32, and prevent the gas flow rate from being too fast and causing impact damage to the first fuel cell stack 2 and the second fuel cell stack 3. The area of ​​the first fuel chamber 1312 (or the second fuel chamber 1412) can be greater than or equal to the area of ​​the first fuel inlet (or the second fuel inlet 32). When the area of ​​the first fuel chamber 1312 (or the second fuel chamber 1412) is greater than the area of ​​the first fuel inlet (or the second fuel inlet 32), it is not only convenient to adapt to fuel cells with different fuel inlet specifications, but also because the area of ​​the first fuel chamber 1312 (or the second fuel chamber 1412) is large enough, the gas flow rate can be reduced, allowing the gas to smoothly enter the internal flow channel of the fuel cell stack.

[0039] Furthermore, the difference in pressure drop between the first fuel channel 1311 and the second fuel channel 1411 does not exceed 10% to improve module stability. The fuel gas passes through the first fuel channel 1311 and the second fuel channel 1411, respectively, then enters the independently separated first fuel chamber 1312 and the second fuel chamber 1412, and finally flows to the first fuel cell stack 2 and the second fuel cell stack 3. Preferably, the difference in pressure drop between the first fuel channel 1311 and the second fuel channel 1411 does not exceed 5%.

[0040] Furthermore, the pressure loss of the first fuel channel 1311 is greater than the pressure loss between the first fuel outlet and the first fuel inlet, and the pressure loss of the second fuel channel 1411 is greater than the pressure loss between the second fuel outlet 31 and the second fuel inlet 32 ​​.

[0041] It is understandable that since the flow rates entering the first and second battery stacks 2 and 3 in the module must be consistent, inconsistent flow rates will affect the power generation performance and operational stability of the module or system. However, there are inevitable processing errors between the first and second battery stacks 2 and 3 or between modules, resulting in inconsistent flow rates allocated between the first and second battery stacks 2 and 3 (i.e., inconsistent pressure losses at constant flow temperature). This embodiment sets the above-mentioned pressure loss requirements so that the total pressure loss is large enough to ignore the problem of inconsistent flow rates caused by processing errors between the first and second battery stacks 2 and 3 or between modules.

[0042] It can also be understood that the total pressure loss of this embodiment includes the pressure loss of the first fuel channel 1311 and the pressure loss between the first fuel outlet and the first fuel inlet, the pressure loss of the second fuel channel 1411 and the pressure loss between the second fuel outlet 31 and the second fuel inlet 32.

[0043] Furthermore, first fuel channel 1311 includes a first inlet section and a first outlet section. The first outlet section is connected to first fuel chamber 1312. The first inlet section is externally connected to a fuel source, and the inner diameter of the first inlet section is larger than the inner diameter of the first outlet section. In this embodiment, fuel enters from the first inlet section and is then output from the first outlet section until it reaches first fuel chamber 1312. It is understood that by providing a transition section with a larger inner diameter at the first inlet section, deformation errors caused by welding or other connection methods at the connection when connecting to the fuel source can be alleviated. In addition, by making the inner diameter of the first inlet section larger than the inner diameter of the second outlet section, a welding avoidance is prevented to prevent deformation caused by overheating during welding, which would affect the flow path accuracy of first fuel channel 1311. The length of the first inlet section is not subject to design requirements; it is sufficient to meet welding requirements.

[0044] Similarly, the second fuel channel 1411 includes a second inlet section and a second outlet section. The second outlet section is connected to the second fuel chamber 1412. The second inlet section is connected to an external fuel source. The inner diameter of the second inlet section is larger than the inner diameter of the second outlet section to serve as a welding avoidance to prevent deformation caused by overheating during welding, which affects the flow channel accuracy of the second fuel channel 1411.

[0045] Furthermore, the first fuel channel 1311 is partially exposed outside the first fuel chamber 1312 and is connected to an external fuel source, and the tail end of the first outlet section is located inside the first fuel chamber 1312. The first outlet section is not directly close to the inner wall of the first fuel chamber 1312 to prevent gas blockage due to thermal expansion or processing errors at high temperatures.

[0046] Similarly, the second fuel channel 1411 is partially exposed outside the second fuel chamber 1412 and is connected to an external fuel source, and the tail end of the second outlet section is located inside the second fuel chamber 1412. The second outlet section is not directly close to the inner wall of the second fuel chamber 1412 to prevent gas blockage due to thermal expansion or processing errors at high temperatures.

[0047] Further, if Figure 3 and Figure 4 As shown, multiple precision tubes 15 are also included. The first fuel channel 1311 is provided with a precision tube 15, and the end of the precision tube 15 facing away from the first fuel chamber 1312 is connected to the fuel source. And / or the second fuel channel 1411 is provided with a precision tube 15, and the end of the precision tube 15 facing away from the second fuel chamber 1412 is connected to the fuel source. It should be noted that the precision tube 15 can be provided only in the first fuel channel 1311 or the second fuel channel 1411, as long as the first fuel channel 1311 or the second fuel channel 1411 without the precision tube 15 meets the above-mentioned pressure loss requirements. Of course, precision tubes 15 can also be provided in both the first fuel channel 1311 and the second fuel channel 1411. Preferably, in this embodiment, precision tubes 15 are provided in both the first fuel channel 1311 and the second fuel channel 1411.

[0048] In this embodiment, the air intake of the first fuel cell stack 2 and the second fuel cell stack 3 is controlled by a precision tube 15, and the first supply area 13 and the second supply area 14 are isolated by an isolation device 12, so that the air intake of the first fuel cell stack 2 and the second fuel cell stack 3 are independently controlled by the precision tube 15, thereby avoiding uneven flow distribution. It should be noted that the first fuel cell stack 2 is an inverted fuel cell stack; that is, the first fuel inlet and the first fuel outlet of the first fuel cell stack 2 are at the bottom, and the second fuel inlet 32 ​​and the second fuel outlet 31 of the second fuel cell stack 3 are at the top. The inverted setting of the first fuel cell stack 2 enables the first fuel cell stack 2 and the second fuel cell stack 3 to share an airflow distribution device 1, which greatly reduces material costs. The positive and negative poles of the inverted first fuel cell stack 2 and the non-inverted second fuel cell stack 3 are oriented in the same direction and are connected in series to output voltage.

[0049] It is understood that the precision tube 15 is a replaceable component. Users can design and insert precision tubes 15 of different inner diameters according to flow rate, pressure drop, and other requirements to achieve pre-control of flow rate and pressure drop, avoid mismatch problems after product formation, and thus reduce manufacturing costs. In addition, the precision tube 15 of this embodiment refers to a steel tube made of a material that is resistant to high temperatures, has minimal deformation during thermal cycling, has no side effects with high-temperature gas, and does not emit volatile or toxic substances (for example, titanium alloy - military alloy). It can adapt to changes in the high-temperature environment of the fuel cell, reduce environmental errors, and improve the accuracy of fuel injection.

[0050] In actual application, there are two first fuel inlets, and the two first fuel inlets are symmetrically designed relative to the first fuel chamber 1312. The internal flow channel design of the first fuel cell stack 2 needs to ensure its gas distribution within the single-layer battery. If there are too many first fuel inlets, the sealing of the first fuel inlets will be difficult. If there are too few first fuel inlets, the design of the single-layer battery distribution flow channel will be difficult. The two first fuel inlets of this embodiment can reduce the difficulty of processing and improve space utilization. Similarly, there are two second fuel inlets 32, and the two second fuel inlets 32 are symmetrically designed relative to the second fuel chamber 1412.

[0051] In this embodiment, the pressure losses of the first fuel channel 1311 and the second fuel channel 1411 are consistent, so that the pressure losses of the first fuel stack 2 and the second fuel stack 3 are consistent, thereby improving the stability of the module. The fuel gas passes through two precision tubes 15 and then enters the independently separated first fuel chamber 1312 and the second fuel chamber 1412 respectively, and finally enters the first fuel stack 2 and the second fuel stack 3.

[0052] It can be understood that since the geometric dimensions of the precision tube 15 determine the pressure loss of the entire first fuel channel 1311 and the second fuel channel 1411, and the gas flow rate in the precision tube 15 is fast and its inner diameter is small, this embodiment controls the geometric dimensions of the two precision tubes 15 and symmetrically arranges the two precision tubes 15 so that under the condition of qualified tolerances, the pressure losses of the first fuel channel 1311 and the second fuel channel 1411 meet the consistency.

[0053] Furthermore, the first fuel channel 1311 is located on the central axis of the first fuel chamber 1312 ; the second fuel channel 1411 is located on the central axis of the second fuel chamber 1412 .

[0054] The first fuel inlet of this embodiment is symmetrically designed relative to the first fuel chamber 1312, and the second fuel inlet 32 ​​is symmetrically designed relative to the second fuel chamber 1412. At the same time, the first fuel channel 1311 is located on the central axis of the first fuel chamber 1312, and the second fuel channel 1411 is located on the central axis of the second fuel chamber 1412. This can ensure that after the fuel gas enters the first fuel chamber 1312 and the second fuel chamber 1412, the amount of fuel gas distributed to the left and right two first fuel inlets of the first fuel stack 2 and the left and right two second fuel inlets 32 of the second fuel stack 3 is sufficiently uniform.

[0055] Furthermore, the pressure loss of the precision tube 15 is greater than the pressure loss between the first fuel outlet and the first fuel inlet, and / or the pressure loss of the precision tube 15 is greater than the pressure loss between the second fuel outlet 31 and the second fuel inlet 32 ​​.

[0056] It is understandable that since the flow rates entering the first fuel cell 2 and the second fuel cell 3 in the module need to be consistent, inconsistent flow rates will affect the power generation performance and operational stability of the system. However, there are inevitable processing errors between the first fuel cell 2 and the second fuel cell 3 or between the modules, resulting in inconsistent flow rates allocated between the first fuel cell 2 and the second fuel cell 3 (i.e., inconsistent pressure losses at constant flow temperature). In this embodiment, a precision tube 15 is provided in the first fuel channel 1311 or the second fuel channel 1411 to increase the total pressure loss. When the total pressure loss is large enough, the problem of inconsistent flow rates caused by processing errors between the first fuel cell 2 and the second fuel cell 3 or between the modules can be ignored.

[0057] It can also be understood that the total pressure loss includes the pressure loss of the precision tube 15, the compression between the first fuel outlet and the first fuel inlet, and / or the pressure loss between the second fuel outlet 31 and the second fuel inlet 32. When the pressure loss of the precision tube 15 is much greater than the pressure loss between the first fuel outlet and the first fuel inlet of the first fuel stack 2, the magnitude of the total pressure loss depends on the pressure loss of the precision tube 15, so that the pressure loss difference caused by the processing error between the first fuel stacks 2 at this time can be ignored. Similarly, when the pressure loss of the precision tube 15 is much greater than the pressure loss between the second fuel outlet 31 and the second fuel inlet 32 ​​of the second fuel stack 3, the magnitude of the total pressure loss depends on the pressure loss of the precision tube 15, so that the pressure loss difference caused by the processing error between the second fuel stacks 3 at this time can be ignored. In this embodiment, the pressure loss of the precision tube 15 is greater than the pressure loss between the first fuel outlet and the first fuel inlet, and the pressure loss of the precision tube 15 is greater than the pressure loss between the second fuel outlet 31 and the second fuel inlet 32. In some embodiments, if the precision tube 15 is only provided in the first fuel channel 1311 or the second fuel channel 1411 , it is sufficient for the first fuel channel 1311 or the second fuel channel 1411 where the precision tube 15 is not provided to meet the above-mentioned pressure loss requirements.

[0058] like Figure 4 As shown, the precision tube 15 includes a third inlet section 151 and a third outlet section 152, the first fuel chamber 1312 and / or the second fuel chamber 1412 are connected to the corresponding third outlet section 152, the third inlet section 151 is connected to an external fuel source, and the inner diameter of the third inlet section 151 is larger than the inner diameter of the third outlet section 152.

[0059] In this embodiment, the fuel enters from the third inlet section 151 and is then output from the third outlet section 152 until it reaches the first fuel chamber 1312 or the second fuel chamber 1412. It is understood that at least two precision tubes 15 are provided on an airflow distribution device 1, at least one of which is annularly welded in the first fuel channel 1311, and at least one of which is annularly welded in the second fuel channel 1411. A transition section with a larger inner diameter is provided at the inlet of the precision tube 15 to mitigate deformation errors caused by welding.

[0060] It can also be understood that in order to fix the precision tube 15 in the first fuel channel 1311 or the second fuel channel 1411, the present embodiment adopts welding, so that to fix the precision tube 15, only one end needs to be welded in the first fuel channel 1311 or the second fuel channel 1411; since the first fuel chamber 1312 and the second fuel chamber 1412 are narrow, the third outlet section 152 is inconvenient to weld. The present embodiment adopts the method of welding the third inlet section 151, and by making the inner diameter of the third inlet section 151 larger than the inner diameter of the third outlet section 152, it serves as a welding avoidance to prevent deformation caused by overheating during welding, thereby affecting the flow channel accuracy of the precision tube 15. Among them, there is no design requirement for the length of the third inlet section 151, and it is sufficient to meet the welding requirements. Therefore, the precision tube 15 has an inner diameter and an outer diameter, and the outer diameter of the precision tube 15 is less than or equal to the inner diameter of the first fuel channel 1311 (the second fuel channel 1411). The inner diameter of the precision tube 15 is designed according to the fuel flow rate and the stack pressure drop tolerance required under the standard high-temperature operating conditions of the stack. When in use, different inner diameter specifications can be selected according to actual application requirements and stack specifications.

[0061] Furthermore, the tail end of the third outlet section 152 is located inside the first fuel chamber 1312 or the second fuel chamber 1412; the length of the precision tube 15 is greater than or equal to the first fuel channel 1311, and less than the sum of the lengths of the first fuel channel 1311 and the first fuel chamber 1312; or, the length of the precision tube 15 is greater than or equal to the length of the second fuel channel 1411, and less than the sum of the lengths of the second fuel channel 1411 and the second fuel chamber 1412.

[0062] The tail end of the third outlet section 152 of the precision tube 15 of this embodiment is maintained inside the first fuel chamber 1312 or the second fuel chamber 1412, and is not directly close to the inner wall of the fuel chamber to prevent gas path blockage due to thermal expansion or processing errors at high temperatures. At the same time, the above-mentioned length restriction of the precision tube 15 is used to avoid the precision tube 15 being too short, resulting in a small pressure drop caused by the gas flowing through the precision tube 15, which is insufficient to compensate for the impact of the stack pressure drop tolerance and cannot achieve the distribution target. It should be noted that even if the design is modified, maintaining the same level of pressure drop when the precision tube 15 is too short can easily lead to excessive flow velocity in the tube. When approaching the speed of sound, the fluid characteristics tend to be compressible fluid, and the shock waves and interference generated are difficult to control.

[0063] In summary, an embodiment of the present invention provides an air flow distribution device 1 and a module, which respectively transport fuel to the first fuel cell stack 2 and the second fuel cell stack 3 by setting a first supply area 13 and a second supply area 14, and using an isolation device 12 to separate the first supply area 13 and the second supply area 14, thereby achieving uniform distribution of the fuel intake amount of the first fuel cell stack 2 and the second fuel cell stack 3; in addition, by welding a replaceable precision tube 15 in the first fuel channel 1311 (second fuel channel 1411), the precision pressure loss tube is welded at the inlet, so that after entering the module, the gas is subjected to similar large flow resistance of the precision tube, and the pressure drop before and after the precision tube is similar, thereby being stably and evenly distributed to the first fuel cell stack 2 and the second fuel cell stack 3, without the need to deliberately process complex distribution flow channels at the end plate of the fuel cell stack or the air inlet of the fuel cell stack, thereby reducing the complexity of the process and the cost of fuel cell stack preparation.

[0064] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. An airflow distribution device for distributing airflow between a first stack and a second stack, characterized in that: It includes a main body and an isolation device, the main body has an exhaust gas discharge structure and a first side surface and a second side surface arranged opposite to each other, the exhaust gas discharge structure is respectively connected to the first fuel outlet of the first fuel stack and the second fuel outlet of the second fuel stack, the first side surface is provided with a first supply area, the second side surface is provided with a second supply area, the isolation device is provided between the first supply area and the second supply area to separate the first supply area from the second supply area, the first supply area has a first fuel supply structure, the two ends of the first fuel supply structure are respectively connected to the first fuel inlet and the fuel source of the first fuel stack, the second supply area has a second fuel supply structure, the two ends of the second fuel supply structure are respectively connected to the second fuel inlet and the fuel source of the second fuel stack.

2. The air flow distribution device according to claim 1, characterized in that: The first fuel supply structure includes a first fuel channel and a first fuel chamber, the first fuel chamber is arranged corresponding to the first fuel inlet, and the first fuel chamber is externally connected to the fuel source through the first fuel channel; The second fuel supply structure includes a second fuel channel and a second fuel chamber. The second fuel chamber is arranged corresponding to the second fuel inlet. The second fuel chamber is externally connected to the fuel source through the second fuel channel.

3. The air flow distribution device according to claim 2, characterized in that: The difference in pressure loss between the first fuel channel and the second fuel channel does not exceed 10%.

4. The air flow distribution device according to claim 2 or 3, characterized in that: The pressure loss of the first fuel passage is greater than the pressure loss between the first fuel outlet and the first fuel inlet, and the pressure loss of the second fuel passage is greater than the pressure loss between the second fuel outlet and the second fuel inlet.

5. The air flow distribution device according to claim 4, characterized in that: The first fuel channel includes a first inlet section and a first outlet section, the first outlet section is in communication with the first fuel chamber, the first inlet section is externally connected to the fuel source, and the inner diameter of the first inlet section is larger than the inner diameter of the first outlet section; The second fuel channel includes a second inlet section and a second outlet section. The second outlet section is communicated with the second fuel chamber. The second inlet section is externally connected to the fuel source. The inner diameter of the second inlet section is larger than the inner diameter of the second outlet section.

6. The air flow distribution device according to claim 5, characterized in that: The first fuel channel is partially exposed outside the first fuel chamber and is externally connected to the fuel source, and the tail end of the first outlet section is located inside the first fuel chamber; The second fuel channel is partially exposed outside the second fuel chamber and connected to the fuel source, and the tail end of the second outlet section is located inside the second fuel chamber.

7. The air flow distribution device according to claim 2, characterized in that: The system further includes a plurality of precision tubes, wherein the first fuel channel is provided with the precision tubes, and one end of the precision tube facing away from the first fuel chamber is connected to the fuel source, and the pressure loss of the precision tubes is greater than the pressure loss between the first fuel outlet and the first fuel inlet; and / or, The second fuel channel is provided with the precision tube, and one end of the precision tube away from the second fuel chamber is connected to the fuel source, and the pressure loss of the precision tube is greater than the pressure loss between the second fuel outlet and the second fuel inlet.

8. The air flow distribution device according to claim 7, characterized in that: The precision tube includes a third inlet section and a third outlet section. The first fuel chamber and / or the second fuel chamber is connected to the corresponding third outlet section. The third inlet section is externally connected to the fuel source. The inner diameter of the third inlet section is larger than the inner diameter of the third outlet section.

9. The air flow distribution device according to claim 8, characterized in that: The tail end of the third outlet section is located inside the first fuel chamber or the second fuel chamber; The length of the precision tube is greater than or equal to the first fuel channel and less than the sum of the lengths of the first fuel channel and the first fuel chamber; or, the length of the precision tube is greater than or equal to the length of the second fuel channel and less than the sum of the lengths of the second fuel channel and the second fuel chamber.

10. A module, characterized in that: It includes a first fuel cell stack, a second fuel cell stack and an air flow distribution device as described in any one of claims 1 to 9, the first fuel cell stack and the second fuel cell stack are stacked, and the air flow distribution device is located between the first fuel cell stack and the second fuel cell stack, the two ends of the first fuel supply structure are respectively connected to the first fuel inlet and the fuel source of the first fuel cell stack, the two ends of the second fuel supply structure are respectively connected to the second fuel inlet and the fuel source of the second fuel cell stack, and the exhaust gas discharge structure is respectively connected to the first fuel outlet of the first fuel stack and the second fuel outlet of the second fuel stack.

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