Proton exchange membrane fuel cell runner optimization method, device, equipment and medium

Abstract

The invention provides a proton exchange membrane fuel cell flow channel optimization method, device, equipment and medium, and relates to the technical field of cell flow channel optimizing.According to the method, a variable-cross-section multi-cell structure flow channel is designed, the cross section of the variable-cross-section multi-cell structure flow channel is in an isosceles trapezoid shape, the variable-cross-section multi-cell structure flow channel is gradually shrunk in the gas flowing direction, and gas distribution and water removal performance are effectively improved; and meanwhile, the arc tangent wave line type design is adopted, so that the gas flow resistance and pressure drop are further reduced. In addition, the flow channel performance is accurately evaluated by calculating the current density improvement degree caused by the change of unit structure parameters. The invention aims to significantly improve the performance and efficiency of a fuel cell and solve the problems of current density reduction and overall efficiency reduction caused by uneven gas distribution, insufficient oxygen supply and liquid water accumulation of a traditional wave-shaped flow channel under high current density.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery flow channel optimization, in particular to a proton exchange membrane fuel cell flow channel optimization method, device, equipment and medium. BACKGROUND

[0002] Under the background of energy transformation, proton exchange membrane fuel cell (PEMFC) as a clean and efficient energy conversion technology has attracted widespread attention. Its working principle is to convert chemical energy into electrical energy through the electrochemical reaction of hydrogen and oxygen on both sides of the proton exchange membrane, which has the advantages of high energy conversion efficiency, environmental friendliness, low temperature start-up speed, etc. It is considered as a potential future energy solution, especially suitable for electric vehicles, distributed power generation and other fields. However, in practical application, the performance of PEMFC is restricted by many factors, among which the design of flow channel structure is particularly important. The role of flow channel is to guide the uniform distribution of reaction gas (hydrogen and oxygen) to the electrode surface, while discharging the water produced in the reaction process. Although the traditional flow channel design, such as straight line and wave type flow channel, can meet the basic gas delivery and water management needs to a certain extent, there are still many problems under high current density conditions.

[0003] Specifically, first, the traditional wave type flow channel is prone to local oxygen concentration too low in the process of gas flow. This is because in the latter part of the flow channel, with the large consumption of oxygen, the gas distribution becomes uneven, leading to insufficient gas supply to the battery catalyst layer and significant decrease in current density. Second, the problem of liquid water management is also a shortcoming of traditional flow channel design. If the water produced in the reaction process cannot be discharged in time, it will accumulate in the flow channel and form a "waterlogging" phenomenon, further hindering the transmission of gas, seriously affecting the performance and life of the fuel cell. In addition, the pressure drop problem of traditional flow channel cannot be ignored. Excessive pressure drop will increase the parasitic power of fuel cell and reduce the overall energy conversion efficiency, which is extremely disadvantageous in practical application.

[0004] However, the existing improvement schemes still have shortcomings although they can alleviate these problems to a certain extent. For example, some designs optimize gas distribution by changing the depth or width of the flow channel, but these improvements do not fundamentally solve the problems of water accumulation and uneven gas distribution in the flow channel. Although some schemes attempt to reduce pressure drop by changing the arrangement of the flow channel, they often compromise in terms of gas uniformity and water management. These improvement measures often accompany the decline of other performance indicators while improving the performance of fuel cell, making it difficult to achieve overall performance improvement.

[0005] In summary, the existing proton exchange membrane fuel cell flow channel design still faces many challenges under high current density conditions, such as uneven gas distribution, difficult liquid water management, and excessive pressure drop. These problems limit the further improvement of fuel cell performance, so there is an urgent need for a new flow channel structure design that can optimize gas distribution, improve water removal performance, and effectively reduce pressure drop to improve the overall performance and efficiency of fuel cells. This is not only a demand for technological development, but also a key to promoting the large-scale commercial application of proton exchange membrane fuel cells.

[0006] In view of this, the present application is proposed. SUMMARY

[0007] The present application provides a proton exchange membrane fuel cell flow channel optimization method, device, equipment and medium, which can at least partially improve the above problems.

[0008] To achieve the above object, the present application adopts the following technical scheme: A proton exchange membrane fuel cell flow channel optimization method, comprising: Obtaining a traditional cell wave-shaped flow channel structure, performing shape modification preprocessing on the traditional cell wave-shaped flow channel structure to obtain an initial variable cross-section multi-cell flow channel structure, wherein the cross-sectional shape of the initial variable cross-section multi-cell flow channel structure is an isosceles trapezoid; According to the initial variable cross-section multi-cell flow channel structure, a three-dimensional model is established, the types of structure parameters causing current density changes are determined, and the specific current densities under different numerical conditions are calculated based on the control variable method; The best specific current density is selected from the plurality of specific current densities as the optimal specific current density, and the initial variable cross-section multi-cell flow channel structure corresponding to the optimal specific current density is used as the final variable cross-section multi-cell flow channel structure.

[0009] The present application also provides a proton exchange membrane fuel cell flow channel optimization device, comprising: A preprocessing unit is configured to obtain a traditional cell wave-shaped flow channel structure, perform shape modification preprocessing on the traditional cell wave-shaped flow channel structure, and obtain an initial variable cross-section multi-cell flow channel structure, wherein the cross-sectional shape of the initial variable cross-section multi-cell flow channel structure is an isosceles trapezoid; An optimization unit is configured to establish a three-dimensional model according to the initial variable cross-section multi-cell flow channel structure, determine the types of structure parameters causing current density changes, and calculate the specific current densities under different numerical conditions based on the control variable method; A screening unit is configured to select the best specific current density from the plurality of specific current densities as the optimal specific current density, and use the initial variable cross-section multi-cell flow channel structure corresponding to the optimal specific current density as the final variable cross-section multi-cell flow channel structure.

[0010] The application further provides a proton exchange membrane fuel cell flow channel optimization device, comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor implements the proton exchange membrane fuel cell flow channel optimization method according to any one of the above when executing the computer program.

[0011] The application further provides a readable storage medium comprising a computer program stored therein, wherein the computer program can be executed by a processor of a device where the readable storage medium is located to implement the proton exchange membrane fuel cell flow channel optimization method according to any one of the above.

[0012] In summary, the proton exchange membrane fuel cell flow channel optimization method is an innovative flow channel design and optimization method proposed for the performance bottleneck of proton exchange membrane fuel cells under high current density conditions. Through ingenious structural improvement, the key problems of uneven gas distribution, insufficient oxygen supply, liquid water accumulation, and excessive pressure drop in traditional flow channel design are effectively solved. The core of the method is a new variable cross-section multi-cell flow channel structure, which significantly improves the gas flow efficiency and water removal performance through the unique design of isosceles trapezoidal cross-section and tapered layout combined with circular arc tangent wavy lines. In addition, the method also introduces an optimization step based on specific current density, which can accurately evaluate the flow channel performance to determine the optimal combination of structural parameters. Experimental verification shows that this design not only significantly improves the current density of the fuel cell, but also significantly reduces the accumulation of liquid water and pressure drop, and the overall performance is significantly improved. This innovative technology provides strong technical support for the efficient operation and commercialization of proton exchange membrane fuel cells, and has broad application prospects. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a flow chart of the proton exchange membrane fuel cell flow channel optimization method provided by the first embodiment of the application; Figure 2 is a 3D structure diagram of the variable cross-section multi-cell flow channel provided by the embodiment of the application; Figure 3 is a top surface structure diagram of the variable cross-section multi-cell flow channel provided by the embodiment of the application; Figure 4 is a bottom surface structure diagram of the variable cross-section multi-cell flow channel provided by the embodiment of the application; Figure 5 is a side surface structure diagram of the variable cross-section multi-cell flow channel provided by the embodiment of the application; Figure 6 is a first specific current density comparison diagram provided by the embodiment of the application; Figure 7 is a second specific current density comparison diagram provided by the embodiment of the application; Figure 8is a pressure drop comparison chart provided by the embodiment of the present application; Figure 9 is a 3D structure chart of a traditional wave flow channel provided by the embodiment of the present application; Figure 10 is an upper and lower bottom surface structure chart of a traditional wave flow channel provided by the embodiment of the present application; Figure 11 is a side surface structure chart of a traditional wave flow channel provided by the embodiment of the present application; Figure 12 is a current density polarization curve comparison chart provided by the embodiment of the present application; Figure 13 is a diffusion layer liquid water mass fraction comparison chart provided by the embodiment of the present application; Figure 14 is a module schematic diagram of a proton exchange membrane fuel cell flow channel optimization device provided by the second embodiment of the present application. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be further described in detail below with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0015] Reference Figure 1 The first embodiment of the present application discloses a proton exchange membrane fuel cell flow channel optimization method, which can be executed by a proton exchange membrane fuel cell flow channel optimization device (hereinafter referred to as an optimization device), and in particular, by one or more processors in the optimization device to execute the following method: S1, obtaining a traditional cell wave flow channel structure, performing shape modification preprocessing on the traditional cell wave flow channel structure to obtain an initial variable cross-section multi-cell flow channel structure, wherein the cross-sectional shape of the initial variable cross-section multi-cell flow channel structure is isosceles trapezoidal; Specifically, step S1 includes that the upper surface and the lower surface of the initial variable cross-section multi-cell flow channel structure are horizontal, and the two side surfaces of the initial variable cross-section multi-cell flow channel structure are wave-shaped, wherein the trapezoidal cross-sectional height of the initial variable cross-section multi-cell flow channel structure gradually decreases along the gas flow direction.

[0016] The wave line type of the initial variable cross-section multi-cell flow channel structure adopts a circular arc tangent design, and its function form is: wherein r is the circular arc radius, A is the wave amplitude, and λ is the wave length.

[0017] The range of the circular arc radius r is 0.5mm-5.8mm, the range of the wave amplitude A is 0.1mm-0.2mm, and the range of the wave length λ is 0.5mm-5.8mm. the initial variable cross-section multi-cell flow channel structure has an upper surface width W1 at the inlet fixed at 0.8 mm, an upper surface width W2 at the outlet ranging from 1 mm to 1.2 mm, a lower surface width W3 at the inlet fixed at 1.2 mm, a lower surface width W4 at the outlet fixed at 1.2 mm, a total length L0 of the wave structure of the initial variable cross-section multi-cell flow channel structure being 48 mm, a total length L of the initial variable cross-section multi-cell flow channel structure being 50 mm, an inlet height H of the initial variable cross-section multi-cell flow channel structure being fixed at 1 mm, and an outlet height h of the initial variable cross-section multi-cell flow channel structure ranging from 0.2 mm to 0.5 mm.

[0018] In the present embodiment, a conventional wave-shaped flow channel structure is taken as a basis, and on this basis, the shape of the conventional flow channel is modified to form an initial variable cross-section multi-cell flow channel structure. The cross-sectional shape of the conventional flow channel is designed as an isosceles trapezoid, and the upper surface and the lower surface remain horizontal, while the two side surfaces are in a wave shape. In view of the phenomenon that the supply of reaction gas inside the battery is insufficient and the diffusion is uneven in the rear section of the flow channel due to the large consumption of oxygen, a taper structure is introduced into the conventional wave structure. This unique design makes the cross-sectional height of the flow channel gradually decrease in the direction of gas flow, reduces the cross-sectional area of the flow channel in the direction of gas flow, and thus increases the gas flow speed, so that the reaction gas enters the gas diffusion layer faster in the rear section of the flow channel and is more easily diffused uniformly, thereby forcing more oxygen to enter the catalyst layer, improving the oxygen concentration in the catalyst layer of the battery, and improving the current density of the battery. The problem of excessive longitudinal wave pressure drop is improved, thereby optimizing the gas flow path and ensuring uniform gas distribution in the rear half of the flow channel, thereby improving the current density.

[0019] Compared with the conventional rectangular cross-section, this isosceles trapezoidal cross-section can effectively reduce the water accumulation on both sides of the flow channel, while increasing the contact area between the flow channel and the gas diffusion layer, thereby promoting the diffusion of reactants and significantly improving the water removal performance and the gas distribution uniformity of the reactants and local current density in the reaction area. In short, the transverse wave arrangement replaces the longitudinal wave arrangement, which increases the contact area between the gas and the catalyst layer, prolongs the residence time of the gas in the flow channel, makes the reaction area larger, and makes the current density distribution more uniform. Moreover, the transverse arrangement is better than the longitudinal arrangement in processing. The depth of the wave flow channel structure is the vertical distance between the upper surface and the lower surface of the flow channel.

[0020] Further, in the wavy design, a circular arc tangent method is also adopted. Compared with the traditional sinusoidal wave, this design has a more gentle circular arc curvature change, which can significantly reduce gas flow resistance and pressure loss; and compared with the sine function, the processing of the circular arc is easier. In terms of specific parameters, the circular arc radius ranges from 0.5mm to 5.8mm, the wave amplitude ranges from 0.1mm to 0.2mm, and the wave length ranges from 1.6mm to 6mm. Reasonable selection of these parameters not only optimizes the gas flow characteristics, but also takes into account the ease of processing and cost-effectiveness. In terms of the specific size design of the flow channel, the upper surface width at the inlet is fixed at 0.8mm, the upper surface width at the outlet ranges from 1mm to 1.2mm, and the lower surface width at the inlet and the outlet is fixed at 1.2mm. The total length of the wavy structure is 48mm, the total length of the flow channel is 50mm, the inlet height is fixed at 1mm, and the outlet height ranges from 0.2mm to 0.5mm. These precise size parameter settings ensure that the flow channel can maximize its performance advantages while meeting the gas flow and reaction requirements.

[0021] Specifically, the detailed structure parameters of the gas flow channel are shown in Table 1, and the structure diagram of the flow channel is shown in Figures 2 to 5 The one end of the length direction of the flow channel is the gas inlet, and the other end is the gas outlet.

[0022] Table 1: Structure parameters of variable cross-section multi-cell flow channel

[0023] S2, based on the initial variable cross-section multi-cell flow channel structure, a three-dimensional model is established, the types of structure parameters causing current density change are determined, and the specific current density under different numerical conditions is calculated based on the control variable method; Specifically, step S2 includes: establishing a three-dimensional model of a proton exchange membrane fuel cell with the initial variable cross-section multi-cell flow channel structure on Fluent software, and performing grid division processing on the three-dimensional model based on ICEM software to generate a body grid; The body grid is imported into the Fluent software, and the material, property, and boundary condition are defined for finite element calculation to obtain the current density polarization curve and post-processing results of the fuel cell, and the post-processing results are imported into the CFD-POST software; According to the post-processing results, the types of structure parameters causing current density change are determined, including wave length, wave amplitude, and outlet height; Based on the preset parameter data set and the control variable method, the numerical size of the wave length, the wave amplitude, and the outlet height is adjusted respectively to determine the current density under different numerical conditions, and the difference value of the current density and the corresponding parameter change value are calculated according to the current density under different numerical conditions ​ ; The specific current density is calculated according to the formula under different numerical conditions, wherein the parameter variation amount includes the waveform wavelength variation amount , the waveform amplitude variation amount , and the outlet height variation amount .

[0024] In this embodiment, in order to more accurately evaluate the performance of the fuel cell with the variable cross-section multi-cell structure flow channel, the specific current density is defined. Wherein, is the change value of the structural parameter affecting the performance of the fuel cell, is the change value of the current density before and after, and then represents the degree of improvement of the performance of the fuel cell per unit caused by the change of the parameter per unit.

[0025] Specifically, first, a three-dimensional model of a proton exchange membrane fuel cell with an initial variable cross-section multi-cell flow channel structure is established on the Spaceclaim software, and the model is verified. This step is the basis of the entire optimization process. Through accurate modeling, accurate geometric structure information can be provided for subsequent simulation calculation. Then, the three-dimensional model is meshed based on ICEM software, and the body mesh is automatically generated according to the divided surface mesh, and a total of 652,940-860,560 meshes are generated. The quality of meshing directly affects the accuracy and efficiency of finite element calculation, so it is necessary to ensure that the generated body mesh can fully capture the flow details and physical phenomena in the flow channel.

[0026] The generated body mesh is imported into the Fluent software, and key parameters such as materials, properties, and boundary conditions are defined. Accurate setting of these parameters is the key to ensuring the reliability of the simulation results. After completing the above preparation work, finite element calculation is performed to obtain the current density polarization curve and post-processing results of the fuel cell. The current density polarization curve is an important indicator for evaluating the performance of the fuel cell. By analyzing the curve, the performance of the fuel cell under different working conditions can be intuitively understood. The post-processing results contain more detailed information, which provides data support for subsequent parameter analysis. Subsequently, the post-processing results are imported into the CFD-POST software. The powerful post-processing function of the CFD-POST software can help to analyze the simulation results more deeply and extract key information. According to the post-processing results, the types of structural parameters that cause the change of the current density are determined, including the waveform wavelength, the waveform amplitude, and the outlet height. These structural parameters have a significant impact on the performance of the fuel cell. Through optimization and adjustment of them, the performance of the fuel cell can be improved.

[0027] According to the post-processing results, the structural parameters causing the current density can be determined as the waveform wavelength, the waveform amplitude and the outlet height; based on the preset parameter data set and the control variable method, the numerical size of the waveform wavelength, the waveform amplitude and the outlet height is adjusted respectively. The control variable method is a scientific experimental method, by changing the numerical value of a certain parameter one by one, while keeping other parameters unchanged, the influence of the parameter on the current density can be clearly observed. After adjusting the parameter each time, the finite element calculation is performed again to determine the current density under different numerical conditions, and the difference of the current density and the corresponding parameter change amount under different numerical conditions are calculated.

[0028] Finally, the specific current density under a plurality of different numerical conditions is calculated according to the formula. The specific current density is an important evaluation index proposed by the method, which can more accurately reflect the influence degree of the change of the structural parameters on the performance of the fuel cell. By calculating the specific current density, the performance under different parameter combinations can be quantitatively evaluated, thereby providing a scientific basis for determining the optimal structural parameters. Among them, the parameter change amount includes the waveform wavelength change amount, the waveform amplitude change amount and the outlet height change amount. By comparing the specific current density under different conditions, the most effective parameter combination in improving the performance of the fuel cell can be screened out, and then the optimal design of the flow channel structure of the fuel cell is realized.

[0029] Thus, the specific current density of the variable cross-section multi-cell flow channel fuel cell is shown in Table 2, Table 3 and Table 4.

[0030] Table 2 Outlet height H of cathode Specific current density

[0031] Table 3 Amplitude A Specific current density

[0032] Table 4 Wavelength Specific current density

[0033] According to the analysis of Table 2, Table 3 and Table 4 and Figure 6 , when the wavelength is 2.4 mm, the amplitude A is 0.2 mm, and the outlet height h of the cathode flow channel is 0.3 mm (i.e. Case 4), the variable cross-section multi-cell flow channel fuel cell has the maximum specific current density, and in Figure 6 , it can also be found that compared with the change of the wavelength and the amplitude A, the change of the outlet height h of the cathode flow channel is more obvious in improving the current density of the fuel cell, and therefore should be considered first in the design. It is worth noting that although the wavelength The current density can be increased to 1.6 mm or the cathode flow channel outlet height h is reduced to 0.2 mm (corresponding to Case 5 and Case 13), which can obtain higher current density, but due to the smaller specific current density at this time, the current density is increased by a small amount, and the current density of Case 4 is 1.085 A / cm 2 , reaching 99.5% and 99.7% of the current density in the previous two cases, by Figure 8 It is known that the pressure drop is reduced by 34.4% and 37.2%, which shows that the flow channel structure with higher specific current density helps to reduce the parasitic power of the fuel cell, and ultimately improves the overall efficiency of the fuel cell.

[0034] The current density increases with the decrease of the wavelength, the increase of the amplitude, and the decrease of the outlet height, but the current density growth brought by the change of the above parameters is not infinite, but becomes smaller and smaller with the change of the parameters, and even negative. Because the change of the above parameters will lead to the complexity of the internal structure of the flow channel, which will cause the increase of the internal pressure drop of the fuel cell. When the maximum current density is approached, it is often accompanied by a huge pressure drop, which makes it necessary to increase the power consumption of the auxiliary system, and ultimately reduces the overall output of the fuel cell. In the current density curve, the maximum specific current density often appears in front of the maximum current density position, and the current density growth rate reaches the maximum at this time, causing the current density to increase by the maximum, and the corresponding pressure drop is much smaller than that at the maximum current density. Therefore, the performance of the fuel cell can be improved to the maximum extent by comprehensive consideration.

[0035] Taking Figure 7 Case 1-5 as an example, the specific current density of Case 4 is the largest (corresponding to the maximum slope of the curve), which appears in front of the maximum current density Case 5, and the corresponding pressure drop is much smaller than that of Case 5. After several changes in parameter combination, the structure parameters of Case 4 in the variable cross-section multicellular flow channel are finally determined to be the optimal, so Case 4 is taken as an embodiment of the present application. Compared with Figures 9 to 11 the traditional wave flow channel (adopting the same wave line design as the variable cross-section multicellular flow channel of Case 4, the upper and lower surface widths of the inlet and outlet of the flow channel are fixed as W4=1 mm, and the outlet heights of the inlet and outlet of the flow channel are all H=1 mm), wherein one end of the length direction of the flow channel is the gas inlet, and the other end is the gas outlet; by Figure 12 the maximum current density of the fuel cell is increased by 11.8%, by Figure 13 the maximum liquid water mass fraction is decreased by 1.64%. The detailed parameters of the wave tapered flow channel (embodiment Case 4) and the traditional wave flow channel (comparative example) are shown in Table 5.

[0036] Table 5

[0037] In this embodiment, the proton exchange membrane fuel cell flow channel optimization method provides a calculation method for specific current density, which can improve the final performance of the fuel cell while avoiding excessive parasitic power caused by excessive pressure drop, provide a new evaluation standard for the design of fuel cell flow channels, and more accurately optimize the structure of the fuel cell.

[0038] S3, from the plurality of specific current densities, the best effect specific current density is selected as the optimal specific current density, and the corresponding initial variable cross-section multi-cell flow channel structure is selected as the final variable cross-section multi-cell flow channel structure.

[0039] In this embodiment, after a series of complex simulation calculations and data analysis are completed, the screening step is entered. The core task of this stage is to accurately screen the best specific current density from the numerous calculated specific current densities, select it as the optimal specific current density, and determine the initial variable cross-section multi-cell flow channel structure corresponding to it as the final variable cross-section multi-cell flow channel structure. This step is the final step of the entire optimization process, which directly determines the final result of the fuel cell flow channel structure optimization and plays a crucial role in improving the overall performance of the fuel cell.

[0040] Specifically, during the previous finite element simulation calculation process, by changing the structural parameters such as wave length, wave amplitude and outlet height, specific current densities under multiple numerical conditions are obtained. These specific current densities reflect the trend and degree of fuel cell performance under different flow channel structure parameter configurations. The level of specific current density is directly related to the performance improvement efficiency of the fuel cell under unit structural parameter change, therefore, screening the highest specific current density means finding the flow channel structure configuration that can maximize the performance of the fuel cell within the current parameter range. After the optimal specific current density is determined, the initial variable cross-section multi-cell flow channel structure corresponding to it becomes the final variable cross-section multi-cell flow channel structure. This structure has undergone strict screening and verification, and is the outstanding candidate among many candidates. It has shown significant advantages in key performance indicators such as gas distribution uniformity, water removal performance and pressure drop control. For example, in terms of gas distribution, this structure can ensure that the reaction gas reaches the electrode surface more uniformly, thereby improving the efficiency of the electrochemical reaction; in terms of water removal performance, it can effectively avoid the accumulation of liquid water in the flow channel, reduce the occurrence of "waterlogging" phenomenon, and ensure the stable operation of the fuel cell; and in terms of pressure drop control, this structure optimizes the gas flow path, reduces the gas flow resistance, and thus reduces the pressure drop, improving the energy conversion efficiency of the fuel cell.

[0041] Ultimately, this optimized variable cross-section multi-cell flow channel structure provides a solid structural foundation for the efficient operation of proton exchange membrane fuel cells. It not only enhances the current density and overall performance of the fuel cell, but also provides a new way of thinking and approach for the design and development of fuel cells. Through this optimization strategy based on specific current density screening, the optimal solution can be quickly and accurately found among numerous possible structural parameter combinations, greatly improving the efficiency and scientificity of fuel cell flow channel structure design. This innovative optimization method is expected to further promote the development of proton exchange membrane fuel cell technology and enable it to play a greater role in the future energy field.

[0042] In summary, the proton exchange membrane fuel cell flow channel optimization method aims to solve the problems of uneven gas distribution, insufficient oxygen supply, liquid water accumulation, and excessive pressure drop commonly encountered in traditional wave-shaped flow channels at high current densities. Through innovative flow channel design and optimization methods, the performance and efficiency of fuel cells are significantly improved, providing strong support for the efficient operation and commercialization of proton exchange membrane fuel cells.

[0043] In terms of flow channel design, the cross-sectional shape of the traditional wave-shaped flow channel is improved to an isosceles trapezoid, and the trapezoidal height gradually decreases along the gas flow direction. This design not only reduces water accumulation on both sides of the flow channel, improving water removal performance, but also increases the contact area between the flow channel and the gas diffusion layer, promoting uniform distribution of reactants. In addition, the wave line of the flow channel is designed with a circular arc tangent, which has a more gradual curvature change compared to the traditional sinusoidal wave shape, significantly reducing gas flow resistance and pressure loss. These improvements effectively solve the "water flooding" phenomenon and uneven gas distribution problems commonly encountered in traditional flow channels at high current densities, significantly improving the current density and stability of fuel cells.

[0044] In terms of optimization methods, a new optimization design method based on specific current density is introduced. By calculating the degree of current density improvement caused by unit structural parameter change, this method can more accurately evaluate the impact of different flow channel structures on fuel cell performance. In actual operation, through finite element simulation calculation and control variable method, the invention determines the optimal flow channel structure parameters, including wave length, wave amplitude, and outlet height. Experimental results show that the optimized flow channel structure not only improves the current density, but also significantly reduces the liquid water mass fraction and pressure drop. Compared with the traditional wave-shaped flow channel, the current density is increased by 11.8%, the liquid water mass fraction is reduced by 1.64%, and the pressure drop is decreased by 34.4% to 37.2%. These improvements not only enhance the output performance of the fuel cell, but also reduce the parasitic power, ultimately improving the overall efficiency of the fuel cell.

[0045] In addition, the flow channel design of the method is also convenient to process. The transverse wave arrangement method is used instead of the longitudinal wave arrangement method, which not only increases the contact area of the gas and the catalyst layer and prolongs the residence time of the gas in the flow channel, but also simplifies the processing technology and reduces the production cost. This design not only improves the performance, but also takes into account the operability and economy in practical application, which provides the possibility for large-scale commercial application of proton exchange membrane fuel cells. In short, the proton exchange membrane fuel cell flow channel optimization method effectively solves many problems of the traditional proton exchange membrane fuel cell flow channel through innovative flow channel design and optimization method, and significantly improves the performance and efficiency of the fuel cell. This technology not only provides a new idea for the design and development of fuel cells, but also provides strong support for the development of future energy technology, and has broad application prospects and important practical significance.

[0046] Referring to Figure 14 The second embodiment of the present application provides a proton exchange membrane fuel cell flow channel optimization device, which comprises: A preprocessing unit 201 is configured to obtain a traditional cell wave-shaped flow channel structure, perform shape modification preprocessing on the traditional cell wave-shaped flow channel structure, and obtain an initial variable cross-section multi-cell flow channel structure, wherein the cross-sectional shape of the initial variable cross-section multi-cell flow channel structure is isosceles trapezoidal. An optimization unit 202 is configured to establish a three-dimensional model according to the initial variable cross-section multi-cell flow channel structure, determine the types of structure parameters causing current density changes, and calculate a plurality of specific current densities under different numerical conditions based on a control variable method. A screening unit 203 is configured to screen the best specific current density from the plurality of specific current densities as an optimal specific current density, and take the initial variable cross-section multi-cell flow channel structure corresponding to the optimal specific current density as a final variable cross-section multi-cell flow channel structure.

[0047] The third embodiment of the present application provides a proton exchange membrane fuel cell flow channel optimization device, which comprises a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor implements the proton exchange membrane fuel cell flow channel optimization method of any one of the above embodiments when executing the computer program.

[0048] The fourth embodiment of the present application provides a readable storage medium, which comprises a computer program stored therein, wherein the computer program can be executed by a processor of a device in which the readable storage medium is located to implement the proton exchange membrane fuel cell flow channel optimization method of any one of the above embodiments.

[0049] Exemplarily, each of the above-described devices and each of the above-described flow steps can be implemented by a computer program, which can be divided into one or more units stored in the memory and executed by the processor to complete the present application.

[0050] The processor can be a central processing unit (CPU), and can also be other general-purpose processors, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0051] The memory can be used to store the computer program and / or modules, and the processor realizes various functions of the present application by running or executing the computer program and / or modules stored in the memory and calling data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application required by a function (such as a sound playing function, an image playing function, etc.), etc.; and the data storage area can store data created based on use of the mobile phone (such as audio data, a phone book, etc.), etc. In addition, the memory can include a high-speed random access memory, and can also include a nonvolatile memory, for example, a hard disk, a memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, at least one disk storage device, a flash storage device, or other volatile solid-state storage device.

[0052] The electronic device or the printer integrated unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the above-mentioned embodiment methods can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer readable storage medium. The computer program can implement the steps of each method embodiment when executed by a processor. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or some intermediate forms. The computer readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the contents of the computer readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer readable medium does not include electrical carrier signals and telecommunication signals.

[0053] It should be noted that the above-described device embodiments are only schematic, and the units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or distributed on multiple network units. Part or all of the modules can be selected to achieve the purpose of the embodiment scheme according to actual needs. In addition, the connection relationship between the modules in the device embodiment provided by the present application indicates that there is a communication connection between them, which can be implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement it without creative labor.

[0054] The above is the preferred embodiment of the present application. It should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which are also considered within the scope of protection of the present application.

Claims

1. A method for flow channel optimization of a proton exchange membrane fuel cell, characterized by, The method comprises the following steps: An initial variable cross-section multi-cell flow channel structure is obtained by acquiring a traditional battery wave-shaped flow channel structure and performing shape modification preprocessing on the traditional battery wave-shaped flow channel structure, wherein the cross-sectional shape of the initial variable cross-section multi-cell flow channel structure is isosceles trapezoidal; A three-dimensional model is established according to the initial variable cross-section multi-cell flow channel structure, the types of structural parameters causing current density changes are determined, and the specific current densities under different numerical conditions are calculated based on the control variable method; The best specific current density is selected from the plurality of specific current densities as the optimal specific current density, and the initial variable cross-section multi-cell flow channel structure corresponding to the optimal specific current density is taken as the final variable cross-section multi-cell flow channel structure.

2. The PEMFC flow channel optimization method of claim 1, wherein, The upper surface and the lower surface of the initial variable cross-section multi-cell flow channel structure are horizontal, and the two side surfaces of the initial variable cross-section multi-cell flow channel structure are wavy, wherein the trapezoidal cross-sectional height of the initial variable cross-section multi-cell flow channel structure gradually decreases along the gas flow direction.

3. The method of flow channel optimization for a PEM fuel cell of claim 2, wherein, The wavy line type of the initial variable cross-section multi-cell flow channel structure adopts a circular arc tangent design, and the function form is: wherein r is a circular arc radius, A is a wave amplitude, is a wave length.

4. The PEMFC flow channel optimization method of claim 3, wherein, The range of the circular arc radius r is 0.5mm-5.8mm, the range of the wave amplitude A is 0.1mm-0.2mm, the range of the wave length of the wave-shaped structure is 1.6mm-6mm, the upper surface width W1 at the inlet of the initial variable cross-section multi-cell flow channel structure is fixed at 0.8mm, the upper surface width W2 at the outlet of the initial variable cross-section multi-cell flow channel structure ranges from 1mm to 1.2mm, the lower surface width W3 at the inlet of the initial variable cross-section multi-cell flow channel structure is fixed at 1.2mm, the lower surface width W4 at the outlet of the initial variable cross-section multi-cell flow channel structure is fixed at 1.2mm, the total length L0 of the wave-shaped structure of the initial variable cross-section multi-cell flow channel structure is 48mm, the total length L of the initial variable cross-section multi-cell flow channel structure is 50mm, the inlet height H of the initial variable cross-section multi-cell flow channel structure is fixed at 1mm, and the outlet height h of the initial variable cross-section multi-cell flow channel structure ranges from 0.2mm to 0.5mm.

5. The PEMFC flow channel optimization method of claim 1, wherein, A three-dimensional model is established according to the initial variable cross-section multi-cell flow channel structure, the types of structural parameters causing current density changes are determined, and the specific current densities under different numerical conditions are calculated based on the control variable method, specifically as follows: A three-dimensional model of a proton exchange membrane fuel cell with the initial variable cross-section multi-cell flow channel structure is established on the Fluent software, and the three-dimensional model is subjected to grid division processing based on the ICEM software to generate a volume grid; The volume grid is imported into the Fluent software, and materials, properties, and boundary conditions are defined for finite element calculation, so as to obtain the current density polarization curve and post-processing results of the fuel cell, and the post-processing results are imported into the CFD-POST software; According to the post-processing results, the types of structural parameters causing current density changes are determined, including the wave length, the wave amplitude, and the outlet height. Based on the preset parameter data set and the control variable method, the numerical size of the waveform wavelength, the waveform amplitude and the outlet height is adjusted respectively, the current density under different numerical conditions is determined, and the difference of the current density under different numerical conditions is calculated according to the current density and the corresponding parameter variation ; According to the formula The specific current density under a plurality of different numerical conditions is calculated, wherein the parameter variation of Including the waveform wavelength variation , the waveform amplitude variation , the outlet height variation The method comprises the following steps: .

6. A method of flow channel optimization for a proton exchange membrane fuel cell, characterized by, The method comprises the following steps: A preprocessing unit is configured to acquire a traditional battery wave-shaped flow channel structure, perform shape modification preprocessing on the traditional battery wave-shaped flow channel structure, and obtain an initial variable cross-section multi-cell flow channel structure, wherein the cross-sectional shape of the initial variable cross-section multi-cell flow channel structure is isosceles trapezoidal; An optimization unit is configured to establish a three-dimensional model according to the initial variable cross-section multi-cell flow channel structure, determine the types of structural parameters causing current density changes, and calculate a plurality of specific current densities under different numerical conditions based on the control variable method; A screening unit is configured to select the best specific current density from the plurality of specific current densities as the optimal specific current density, and take the initial variable cross-section multi-cell flow channel structure corresponding to the optimal specific current density as the final variable cross-section multi-cell flow channel structure.

7. A proton exchange membrane fuel cell flow channel optimization apparatus, characterized by, The processor executes the computer program to implement the proton exchange membrane fuel cell flow channel optimization method of any one of claims 1 to 5.

8. A readable storage medium, characterized by, The computer program can be executed by the processor of the device where the storage medium is located to implement the proton exchange membrane fuel cell flow channel optimization method of any one of claims 1 to 5.

Images