A fuel cell test stand design method and system

Abstract

The present invention relates to the field of structural design technology, specifically a fuel cell test stand design method and system, comprising the following steps: obtaining usage records of test stand components during a typical usage cycle, extracting real-time temperature values, heat flux density values, and heat dissipation power per unit area of ​​each region's heat load node, calculating the heat load level value of each region, classifying the heat load regions, and obtaining heat load region classification results. The present invention classifies the heat load regions of the fuel cell test stand, extracts real-time temperature values, heat flux density values, and heat dissipation power per unit area, calculates the heat load level, and calculates the rib density in combination with the structural strength target, thereby ensuring ventilation and heat dissipation effects while improving structural strength, evaluating the adjusted thermal stress distribution, cyclic loading stability, and ventilation performance parameters, so that the fuel cell test stand has better thermal management capabilities, load adaptability, and overall stability, thereby improving the reliability and efficiency of fuel cell testing.

Description

Technical Field

[0001] The present invention relates to the technical field of structural design, and in particular to a fuel cell test stand design method and system. Background Art

[0002] The field of structural design technology primarily involves the optimization and implementation of various types of equipment, systems, or components in terms of geometric layout, spatial structure, connection methods, and load-bearing characteristics. This field focuses on improving the functional performance, stability, and reliability of equipment through reasonable structural combinations and design solutions. Typical applications include support frame construction, assembly unit layout, connection structure design, modular structure implementation, and material layout optimization. Structural design often combines the specific use environment, mechanical properties, and spatial constraints. Through modeling analysis and engineering implementation, it ensures that the device has good load-bearing capacity, convenient installation and maintenance methods, and efficient space utilization.

[0003] The fuel cell test rack design method is primarily used to construct the support and integrated structure of the fuel cell test platform. This method aims to rationally plan and construct the test rack structure to ensure the orderly arrangement of the gas, electrical, and water systems required for fuel cell testing, while ensuring the stable installation and safe operation of the test equipment. The test rack design aims to accommodate test units, integrate pipeline interfaces, facilitate equipment adjustment and maintenance, and improve the overall operational efficiency and reliability of the test system.

[0004] Traditional design methods use preset structural arrangements and fixed material solutions for construction, failing to fully consider the changes in thermal load during the use cycle and the long-term mechanical response of the material, resulting in local overheating or uneven thermal expansion in high thermal load areas, affecting the stability of the test frame. Material selection is based on experience or unified standards, without targeted optimization based on thermal load distribution and stress characteristics, resulting in redundant or insufficient strength of some components, affecting overall durability. The heat dissipation design mainly relies on the overall ventilation solution, failing to perform local optimization based on the heat flux characteristics of different areas, resulting in uneven heat dissipation effects and heat accumulation problems in some areas. The thermal stress distribution, material adaptability and structural strength have not been comprehensively optimized. The fuel cell test frame will be deformed, suffer local fatigue failure or be inconvenient to maintain during long-term use, affecting the test accuracy and equipment service life. Summary of the Invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a fuel cell test stand design method and system.

[0006] In order to achieve the above-mentioned object, the present invention adopts the following technical solution: a fuel cell test stand design method, comprising the following steps:

[0007] S1: Obtain usage records of test frame components during a typical usage cycle, extract the real-time temperature value, heat flux density value, and heat dissipation power per unit area value of each area's heat load node, calculate the heat load level value of each area, perform heat load area classification, and obtain the heat load area classification results;

[0008] S2: Based on the thermal load area classification results, obtain the number of mechanical cycles, unit component strain range, and contact node continuous loading time of the load-bearing components in the fuel cell test rack during the service life, calculate the material strength grade required for each component, compare with the available material library, identify the matching material for each component, and obtain component material matching information;

[0009] S3: Calling the component material matching information and the heat load area classification result, screening the materials suitable for the high heat load area, performing material replacement, and calculating the adjusted component thickness based on the component strength requirements to obtain the plate replacement information for the heat load area;

[0010] S4: Based on the plate replacement information of the heat load zone and in combination with the heat dissipation target of each zone, the required opening ratio of the baffle member of each zone is calculated. In combination with the strength target of the baffle member, the required reinforcement density of the baffle member is calculated to obtain the partition opening ratio configuration information.

[0011] The present invention has improvements in that the heat load area classification results include a high heat load area, a low heat load area and a heat load transition area; the component material matching information specifically includes the material strength grade, the component fatigue tolerance grade and the material cyclic loading stability evaluation value; the heat load area plate replacement information includes the high heat load area replacement material type, the low heat load area maintenance material type and the structural plate thermal expansion adjustment strategy; the partition opening rate configuration information specifically includes the high heat load area opening rate setting value, the low heat load area opening rate setting value and the airflow guide adjustment parameter.

[0012] The present invention is improved in that the steps of obtaining the heat load area classification result are specifically as follows:

[0013] S111: Obtaining usage records of test frame components during a typical usage cycle, extracting real-time temperature values, heat flux density values, and heat dissipation power per unit area values ​​of heat load nodes in each region, organizing the acquired data in time series to form a temperature curve, heat flux density curve, and heat dissipation power curve distributed over time, establishing a data index, and generating a temperature, heat flux density, and heat dissipation power data series;

[0014] S112: Based on the temperature, heat flux density, and heat dissipation power data sequence, a calculation formula is used:

[0015] ;

[0016] Calculate and obtain the heat load level value, and generate heat load level data;

[0017] in, Represents the thermal load level value, Representative time The temperature value at Representative time The heat flux density value, represents the unit area, represents the total time step;

[0018] S113: Based on the thermal load level data, a set thermal load determination threshold is called to perform thermal load area classification, and areas where the thermal load level value exceeds the threshold are selected as high thermal load areas, and areas where the thermal load level value is lower than the threshold are selected as low thermal load areas, thereby generating a thermal load area classification result.

[0019] The present invention is improved in that the step of obtaining the component material matching information is specifically as follows:

[0020] S211: Based on the thermal load area classification results, the number of mechanical cycles, unit component strain range and contact node continuous loading time of the load-bearing components in the fuel cell test stand during the service life are obtained, the obtained data are sorted, the data index is divided by component, and the cumulative stress change of each component is calculated to generate component stress change data.

[0021] S212: Based on the component stress change data and the target thickness of each component, a calculation formula is used:

[0022] ;

[0023] Obtain the material strength grade required for the component through calculation and generate component material strength grade data;

[0024] in, Represents the material strength grade required for the component, Representative time The number of mechanical cycles, Representative time The strain change of the internal components, Representative time The duration of loading of the inner contact nodes, represents the target thickness of the component, represents the total time step;

[0025] S213: Based on the component material strength grade data, compare with the available material library, screen materials that meet the component material strength requirements, match the mechanical property parameters of the materials, and generate component material matching information.

[0026] The present invention is improved in that the steps for obtaining the replacement information of the heat load zone plate are specifically as follows:

[0027] S311: Call the component material matching information and the heat load area classification result to calculate the temperature distribution of the fuel cell test frame structure plate in the high heat load area, identify the spatial coordinates of the temperature extreme point, and calculate the maximum temperature difference in the area using the formula:

[0028] ;

[0029] The heat flux density in the high heat load area is calculated;

[0030] in, represents the heat flux density in the high heat load area, represents the thermal conductivity of the material, Represents the maximum temperature in the high heat load area, Represents the minimum temperature in the high heat load area, represents the thickness of the test frame structure plate;

[0031] S312: Based on the heat flux density in the high heat load area, calling the material thermal expansion coefficient standard, screening materials that meet the requirements of the high heat load area, extracting the material name, thermal expansion coefficient, thermal conductivity and mechanical strength parameters, calculating the thermal strain of the material in the high heat load area, and obtaining the suitable material for the high heat load area;

[0032] S313: Based on the high heat load area adaptive material and in combination with the component strength requirements, the adjusted component thickness is calculated, the plate configuration is optimized according to the adaptability of the heat load area, and the heat load area plate replacement information is obtained.

[0033] The present invention is improved in that the step of obtaining the partition opening ratio configuration information is specifically as follows:

[0034] S411: Based on the plate replacement information of the heat load area, the unit area heat flux value, the heat dissipation surface area and the gas convection rate ratio of each functional unit of the fuel cell test rack are obtained, the data is sorted, and the unit area heat dissipation capacity of each area is calculated to generate unit area heat dissipation capacity data.

[0035] S412: Based on the heat dissipation capacity per unit area data and in combination with the heat dissipation target of each area, the formula is used:

[0036] ;

[0037] Obtaining the opening ratio of the baffle member in each area by calculation, and generating baffle member opening ratio data;

[0038] in, represents the opening ratio of the baffle component, represents the heat flux per unit area, represents the heat dissipation surface area, represents the gas convection rate, Represents the heat dissipation target, represents the total surface area of ​​the baffle members;

[0039] S413: Based on the baffle member opening rate data and in combination with the strength target of the baffle member, the reinforcement density of the baffle member is calculated to obtain the partition opening rate configuration information.

[0040] The present invention is improved in that the method further comprises:

[0041] S5: Recalling the component material matching information, the heat load zone plate replacement information, and the zone opening ratio configuration information, obtaining the overall thermal stress distribution, cyclic loading stability, and ventilation performance parameters of the adjusted fuel cell test stand, determining the compatibility of the adjusted material and structural configuration, and obtaining structural compatibility test information;

[0042] The structural adaptability test information includes a thermal stress distribution coefficient, a cyclic loading stability parameter, and a ventilation performance evaluation value.

[0043] The present invention is improved in that the steps of obtaining the structural adaptability test information are specifically as follows:

[0044] S511: Calling the component material matching information, the heat load zone plate replacement information, and the zone opening ratio configuration information to obtain the overall thermal stress distribution, cyclic loading stability, and ventilation performance parameters of the adjusted fuel cell test rack, calculate the thermal stress peak, loading stability parameters, and air flow distribution characteristics of each area, and generate thermal stress and ventilation performance data of the fuel cell test rack;

[0045] S512: Based on the thermal stress and ventilation performance data of the fuel cell test stand, a calculation formula is used:

[0046] ;

[0047] Calculate and obtain the suitability of the adjusted material and structural configuration to generate structural suitability data;

[0048] in, represents the structural fitness, Representative time The peak thermal stress at Representative time The material bearing stress at Representative time The air velocity at Representative time The target flow rate, represents the total time step;

[0049] S513: Based on the structural fitness data, the fitness standard is compared to determine whether the adjusted material and structural configurations meet the expected goals, and structural fitness test information is generated.

[0050] A fuel cell test rack design system is provided, wherein the fuel cell test rack design system is used to execute the above-mentioned fuel cell test rack design method, and the system comprises:

[0051] The thermal load classification module obtains the usage records of the test frame components in a typical usage cycle, calculates the thermal load level value of each area, classifies the thermal load areas, and obtains the thermal load area classification results;

[0052] The material matching module calculates the material strength grade required for each component based on the heat load area classification result, identifies the matching material for each component, and obtains component material matching information;

[0053] The heat load area plate adjustment module calls the component material matching information and the heat load area classification result, selects the material suitable for the high heat load area, replaces the material, and obtains the heat load area plate replacement information;

[0054] The opening adjustment module calculates the opening ratio required for the baffle member of each area based on the plate replacement information of the heat load area and the heat dissipation target of each area, and obtains the partition opening ratio configuration information;

[0055] The design effect analysis module calls the component material matching information, the heat load zone plate replacement information and the partition opening ratio configuration information to determine the compatibility of the adjusted material and structural configuration and obtain structural adaptability inspection information.

[0056] Compared with the prior art, the advantages and positive effects of the present invention are:

[0057] In the present invention, the heat load area of ​​the fuel cell test frame is classified, the real-time temperature value, heat flux density value and heat dissipation power per unit area are extracted, the heat load level is calculated, and the preset threshold is called to divide the high and low heat load areas, so that the identification of the heat load distribution is more refined and accurate. The required material strength level is calculated based on the number of mechanical cycles, strain range, contact node loading time and target thickness of the load-bearing component, and the available material library is matched to ensure that the material selection meets the long-term use requirements and avoid the problem of mismatch between material strength and load requirements. Based on the maximum temperature difference and heat flux density in the high heat load area, combined with the material thermal expansion coefficient standard, material replacement is carried out. At the same time, the adjusted component thickness is calculated to optimize the material's heat resistance and overall structural stability, so that the fuel cell test frame has better durability and structural integrity in high-temperature environments. By obtaining the heat flux value per unit area and the ratio of the heat dissipation surface area to the gas convection rate, the opening rate of the baffle component is calculated, and the density of the reinforcement ribs is calculated in combination with the structural strength target to ensure ventilation and heat dissipation effects while improving structural strength. The adjusted thermal stress distribution, cyclic loading stability, and ventilation performance parameters are evaluated, and the adaptability of the structural configuration is determined, so that the fuel cell test frame has better thermal management capabilities, load adaptability, and overall stability, thereby improving the reliability and efficiency of fuel cell testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 is a flow chart of the method of the present invention;

[0059] Figure 2 A flow chart for obtaining heat load area classification results according to the present invention;

[0060] Figure 3 A flow chart for obtaining component material matching information according to the present invention;

[0061] Figure 4 A flow chart for obtaining plate replacement information in a heat load zone according to the present invention;

[0062] Figure 5 A flow chart of obtaining partition opening ratio configuration information of the present invention;

[0063] Figure 6 The flowchart of the present invention is to obtain the structural adaptability test information. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0065] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the devices or elements referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting the present invention. In addition, in the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0066] See also Figure 1 The present invention provides a technical solution: a fuel cell test stand design method, comprising the following steps:

[0067] S1: Obtain usage records of test frame components during a typical usage cycle, extract the real-time temperature value, heat flux density value, and heat dissipation power per unit area of ​​each area's heat load node, calculate the heat load level value of each area, call the set heat load judgment threshold, and classify the heat load areas. Areas exceeding the threshold are selected as high heat load areas, and areas below the threshold are selected as low heat load areas, thereby obtaining the heat load area classification results.

[0068] S2: Based on the thermal load area classification results, the number of mechanical cycles, unit component strain range, and contact node continuous loading time of the load-bearing components in the fuel cell test frame during the service life are obtained. Combined with the target thickness of each accessory, the required material strength grade of each component is calculated. The available material library is compared to identify the matching material for each component and obtain the component material matching information;

[0069] S3: Recall component material matching information and heat load area classification results to obtain the maximum temperature difference and heat flux density of the fuel cell test frame structural plate in the high heat load area. Recall the material thermal expansion coefficient standard to screen materials suitable for the high heat load area, perform material replacement, and calculate the adjusted component thickness size based on the component strength requirements to obtain plate replacement information in the heat load area.

[0070] S4: Based on the plate replacement information of the heat load zone, obtain the unit area heat flux value and the ratio of the heat dissipation surface area to the gas convection rate of each functional unit of the fuel cell test frame. Combined with the heat dissipation target of each area, calculate the required opening ratio of the baffle component of each area. Combined with the strength target of the baffle component, calculate the required reinforcement density of the baffle component, and obtain the partition opening ratio configuration information;

[0071] S5: Call component material matching information, heat load zone plate replacement information and partition opening ratio configuration information to obtain the overall thermal stress distribution, cyclic loading stability and ventilation performance parameters of the adjusted fuel cell test frame, determine the compatibility of the adjusted material and structural configuration, and obtain structural adaptability test information.

[0072] The thermal load area classification results include high thermal load area, low thermal load area and thermal load transition area. The component material matching information specifically includes material strength grade, component fatigue tolerance grade and material cyclic loading stability evaluation value. The thermal load area plate replacement information includes high thermal load area replacement material type, low thermal load area maintenance material type and structural plate thermal expansion adjustment strategy. The partition opening ratio configuration information specifically includes high thermal load area opening ratio setting value, low thermal load area opening ratio setting value and airflow guide adjustment parameters. The structural adaptability test information includes thermal stress distribution coefficient, cyclic loading stability parameters and ventilation performance evaluation value.

[0073] See also Figure 2 , the steps for obtaining the heat load area classification results are as follows:

[0074] S111: Obtaining usage records of test frame components during a typical usage cycle, extracting real-time temperature values, heat flux density values, and heat dissipation power per unit area values ​​of heat load nodes in each region, organizing the acquired data in time series to form a temperature curve, heat flux density curve, and heat dissipation power curve distributed over time, establishing a data index, and generating a temperature, heat flux density, and heat dissipation power data series;

[0075] Obtain the usage records of the test frame components in a typical usage cycle, including the operating status, load level, environmental parameters, etc. at each time point, and extract the real-time temperature value, heat flux density value and unit area heat dissipation power value of the heat load node in each area. The temperature value is collected by the temperature sensor arranged at each node, and the sampling frequency is set to Hz, the data is recorded in the form of time stamps, and the heat flux density value is measured by the thermopile sensor to measure the heat flow per unit area. The measurement range is kW / m2 and converted into a standard data format. The heat dissipation power per unit area is calculated based on the heat flux density and temperature gradient. Each data point is stored in a time series. In the process of data sorting, outliers are removed. The outlier determination method is the mean standard deviation method, that is, the mean of the data series is calculated. and standard deviation , and set the threshold range , data points exceeding the range are removed, threshold and The setting is based on the normal distribution The data points should fall within this range to ensure that the outliers do not affect the overall trend. Affected by environmental stability, the value is small when the test conditions are stable, but it will be large if the temperature fluctuates violently. The data is increased to meet the needs of different test environments. The sorted data is used to construct the temperature curve, heat flux density curve and heat dissipation power curve distributed by time, and a data index is established to optimize the query efficiency. The index adopts the B+ tree structure, which reduces the data retrieval time complexity to , and finally generate temperature, heat flux density and heat dissipation power data series.

[0076] S112: Based on the temperature, heat flux density and heat dissipation power data series, the calculation formula is:

[0077] ;

[0078] Calculate and obtain the heat load level value, and generate heat load level data;

[0079] in, Represents the thermal load level value, Representative time The temperature value at Representative time The heat flux density value, represents the unit area, represents the total time step;

[0080] Based on the temperature, heat flux density and heat dissipation power data series, the calculation formula is called:

[0081] ;

[0082] in, Represents the thermal load level value, Representative time The temperature value at Representative time The heat flux density value, represents the unit area, Represents the total time step. In this calculation process, the data sampling time step is first determined. In this embodiment, Hz sampling, that is Seconds, the unit area is set to , set the temperature value sequence of a certain area to , the heat flux density value sequence is , the formula is calculated as follows:

[0083]

[0084] ;

[0085] Get the heat load level value , and stored in the heat load level data set. The core of this calculation formula is to perform a weighted summation of temperature and heat flux density, and consider the area factor in the calculation process, so as to quantify the heat load level per unit area. The heat load level value increases with the increase of temperature and heat flux density, and the contribution weight of the short-term high temperature or high heat flux area is greater than that of the low temperature and low heat flux area.

[0086] S113: Based on the thermal load level data, the set thermal load determination threshold is called to perform thermal load area classification, and areas where the thermal load level value exceeds the threshold are selected as high thermal load areas, and areas where the thermal load level value is lower than the threshold are selected as low thermal load areas, thereby generating a thermal load area classification result.

[0087] Based on the heat load level data, the set heat load judgment threshold is called to classify the heat load area. The threshold is set based on the temperature influence range of different heat load areas in engineering practice. Specifically, the heat load level exist When the temperature is within the range of 10000, it is classified as the medium heat load area, which corresponds to the stable heat load conditions of common industrial equipment. The area is the high heat load area. This value is selected based on the long-term heat load level that the material can withstand. A value higher than this may increase the heat dissipation demand of the equipment, while a value lower than this may increase the heat dissipation demand of the equipment. The area is a low heat load area and usually does not require additional heat dissipation optimization. According to the above calculation results , belongs to the medium heat load area, the area is marked as the medium heat load area, and the heat load area classification information is updated in the database. The classification results are stored in the system for subsequent thermal management optimization. During the classification process, the set heat load threshold plays the role of defining different heat load areas, and the equipment heat dissipation strategy is adjusted according to the heat load level. High heat load areas may require active cooling measures, such as air cooling or liquid cooling, while low heat load areas can adopt natural heat dissipation. The closer the heat load value is to the threshold boundary, the more refined its adjustment strategy needs to be to avoid classification deviation at the threshold critical point.

[0088] See also Figure 3 ,The specific steps for obtaining component material matching information are:

[0089] S211: Based on the thermal load area classification results, obtain the number of mechanical cycles, unit component strain range, and contact node continuous loading time of the load-bearing components in the fuel cell test rack during the service life, organize the obtained data, divide the data index by component, and calculate the cumulative stress change of each component to generate component stress change data;

[0090] Based on the results of thermal load area classification, the number of mechanical cycles, unit component strain range, and contact node continuous loading time of the load-bearing components in the fuel cell test frame during the service life are obtained. The number of mechanical cycles is monitored in real time by the sensor. Each time the component is subjected to stress loading and reaches a stable state is recorded as a cycle. The data storage frequency is set to Hz, the unit component strain range is measured by the strain gauge, and its value is obtained by calculating the length ratio of the component before and after deformation. The reference strain range is set to The data exceeding this range will be treated as abnormal values. The loading time of the contact node is recorded by the timestamp. The loading time is less than Seconds of recording are not counted as valid data to remove instantaneous vibration interference. After data collection, indexes are established according to component numbers. The cumulative stress change of each component is calculated based on the strain range, number of mechanical cycles and loading time. The stress change is calculated using the Lame stress formula ,in is stress, is the elastic modulus of the material, is the measured strain, and the cumulative stress change is the sum of the stress increments at each measurement time step, as shown in Table 1.

[0091] Table 1 Component mechanical parameter record

[0092]

[0093] As shown in Table 1, each parameter is obtained by measuring equipment and stored in time series, and then used to calculate the cumulative stress change data of the component.

[0094] S212: Based on the component stress change data and the target thickness of each component, the calculation formula is used:

[0095] ;

[0096] Obtain the material strength grade required for the component through calculation and generate component material strength grade data;

[0097] in, Represents the material strength grade required for the component, Representative time The number of mechanical cycles, Representative time The strain change of the internal components, Representative time The duration of loading of the inner contact nodes, represents the target thickness of the component, represents the total time step;

[0098] Based on the component stress change data and the target thickness of each component, the calculation formula is used:

[0099] ;

[0100] in, Represents the material strength grade required for the component, Representative time The number of mechanical cycles, Representative time The strain change of the internal components, Representative time The duration of loading of the inner contact nodes, represents the target thickness of the component, Represents the total time step, in this embodiment, , set the target thickness of a component mm, and the corresponding measurement data are shown in Table 1. The calculation formula is as follows:

[0101] ;

[0102] The material strength grade required for the calculated component is , this value increases with the stress change of the component and is affected by the thickness of the component. The influence of thickness increases, the material strength requirement decreases, and the material strength requirement increases when the thickness decreases.

[0103] S213: Based on the component material strength grade data, compare the available material library, select materials that meet the component material strength requirements, match the mechanical property parameters of the materials, and generate component material matching information;

[0104] Based on the component material strength grade data, compare the available material library and select materials that meet the component material strength requirements. The selection of material strength is based on the material yield strength. and fatigue limit , the materials in the material library must meet conditions, among which is the safety factor, and this embodiment sets , the calculated Substitute and filter materials:

[0105] ;

[0106] Query the material library, select materials that meet the standard, and match their mechanical performance parameters, as shown in Table 2.

[0107] Table 2 Component material matching table

[0108]

[0109] As shown in Table 2, 304 stainless steel, aluminum alloy 7075, and carbon fiber composite materials all meet the material strength requirements, and the final matching component material information is provided for subsequent component production and material selection optimization.

[0110] See also Figure 4 ,The specific steps for obtaining the replacement information of the plate in the heat load area are as follows:

[0111] S311: Call the component material matching information and the heat load area classification results to calculate the temperature distribution of the fuel cell test frame structure plate in the high heat load area, identify the spatial coordinates of the temperature extreme point, and calculate the maximum temperature difference in the area using the formula:

[0112] ;

[0113] The heat flux density in the high heat load area is calculated;

[0114] in, represents the heat flux density in the high heat load area, represents the thermal conductivity of the material, Represents the maximum temperature in the high heat load area, Represents the minimum temperature in the high heat load area, represents the thickness of the test frame structure plate;

[0115] The component material matching information and heat load area classification results are called to calculate the temperature distribution of the fuel cell test frame structure plate in the high heat load area. When obtaining temperature data, the temperature values ​​at different positions of the structure plate are collected using thermocouple sensors. The data collection frequency is set to Hz, and use the interpolation algorithm to spatially supplement the temperature of the unmeasured points to make the temperature distribution data complete. The spatial coordinates of the temperature extreme point are obtained by scanning the measurement point data, and the temperature maximum value of the high heat load area is set. and minimum The thresholds are the highest and lowest values ​​in the temperature data of the area. The selection criteria of extreme points are based on the order of measurement point data, and the highest and lowest values ​​are selected first. The data is averaged and the temperature maximum and minimum are defined based on the average to reduce the impact of local outliers and calculate the maximum temperature difference in the region. , and call the formula:

[0116] ;

[0117] The heat flux density in the high heat load area is calculated, where represents the thermal conductivity of the material, Represents the thickness of the test frame structure plate. In this embodiment, the thickness of the structure plate is selected mm, set the thermal conductivity of the material W / (m·K), maximum temperature in high heat load area °C, minimum temperature °C, then:

[0118] ;

[0119] The final calculation results in the heat flux density of the high heat load area W / m2, this value is affected by the temperature difference and the thermal conductivity of the material. An increase in the temperature difference will increase the heat flux density, and when the thermal conductivity is larger, the heat flux density is higher.

[0120] S312: Based on the heat flux density in the high heat load area, the material thermal expansion coefficient standard is called to screen materials that meet the requirements of the high heat load area. The material name, thermal expansion coefficient, thermal conductivity, and mechanical strength parameters are extracted, and the thermal strain of the material in the high heat load area is calculated to obtain the suitable material for the high heat load area.

[0121] Based on the heat flux density in the high heat load area, the material thermal expansion coefficient standard is called to screen the materials that meet the requirements of the high heat load area. The material screening standard is based on the thermal expansion coefficient. Should meet conditions, among which is the Young's modulus of the material. This embodiment sets the minimum load modulus of the material GPa, and substitute the above calculation results W / m2, calculation filter conditions:

[0122] ;

[0123] ;

[0124] Query the material library, select materials that meet the standard, and match their mechanical performance parameters, as shown in Table 3.

[0125] Table 3 Material screening results for high heat load area

[0126]

[0127] As shown in Table 3, the thermal expansion coefficient of carbon fiber composite materials K It meets the screening criteria and is finally determined to be suitable material for high heat load area.

[0128] S313: Based on the adaptive materials for the high heat load area and the component strength requirements, the adjusted component thickness is calculated. The plate configuration is optimized based on the adaptability of the heat load area, and plate replacement information for the heat load area is obtained.

[0129] Based on the material adaptation in the high heat load area and the component strength requirements, the adjusted component thickness is calculated. The component thickness adjustment standard is based on meeting the thermal strain requirements in the heat load area and setting the adjustment formula: in, is the thickness of the component after adjustment, is the original thickness, To adapt the Young's modulus of the material, the original material of this embodiment is 304 stainless steel, and the Young's modulus is GPa, thickness mm, the suitable material is carbon fiber composite material, Young's modulus GPa, then:

[0130] ;

[0131] Calculate the adjusted component thickness mm, and obtain the plate replacement information in the heat load area after optimization.

[0132] See also Figure 5 , the specific steps for obtaining the partition opening ratio configuration information are as follows:

[0133] S411: Based on the plate replacement information of the heat load area, obtain the unit area heat flux value, heat dissipation surface area and gas convection rate ratio of each functional unit of the fuel cell test rack, organize the data, and calculate the unit area heat dissipation capacity of each area to generate unit area heat dissipation capacity data.

[0134] Based on the replacement information of the plate in the heat load area, the unit area heat flux value, heat dissipation surface area and gas convection rate ratio of each functional unit of the fuel cell test frame are obtained. The unit area heat flux value is calculated from the temperature data measured by the thermocouple sensor. The heat dissipation surface area is obtained based on the surface area statistics of the plate in each area. The gas convection rate ratio is calculated based on the wind speed sensor data, and the flow rate measurement point spacing is set. m, measurement interval s, the convection rate changes in different areas are calculated through multi-point measurements, and the convection rate ratio is used Calculate, where is the highest airflow velocity in the area, is the lowest airflow velocity in the region. This ratio is used to characterize the flow stability in different regions. If the ratio is greater than It is considered as unstable area, below The threshold is selected based on the common ratio range of turbulent and laminar transition in fluid mechanics. The larger the airflow rate ratio, the higher the turbulence of the flow field. This indicates that there is air stagnation or high-speed flow in some local areas, which affects the uniformity of heat dissipation. This shows that the airflow is basically evenly distributed. After sorting the data, the heat dissipation capacity per unit area of ​​each area is calculated. The heat dissipation capacity calculation is based on the heat exchange amount of the plate per unit time, and finally the heat dissipation capacity per unit area data is generated, as shown in Table 4.

[0135] Table 4 Heat dissipation capacity per unit area

[0136]

[0137] As shown in Table 4, the heat dissipation capacity per unit area of ​​each region is calculated comprehensively through the heat flux value, heat dissipation area and gas convection conditions, and is used for the subsequent calculation of the opening ratio.

[0138] S412: Based on the heat dissipation capacity per unit area and the heat dissipation target for each area, the following formula is used:

[0139] ;

[0140] Obtaining the opening ratio of the baffle member in each area by calculation, and generating baffle member opening ratio data;

[0141] in, represents the opening ratio of the baffle component, represents the heat flux per unit area, represents the heat dissipation surface area, represents the gas convection rate, Represents the heat dissipation target, represents the total surface area of ​​the baffle members;

[0142] Based on the heat dissipation capacity per unit area data and the heat dissipation target for each area, the calculation formula is:

[0143] ;

[0144] Calculate the opening ratio of the baffle components in each area, where Represents the regional heat dissipation target and sets the heat dissipation target range W / m2, this range is set according to the thermal load characteristics and industrial standards of the fuel cell test rack. Within this range, the test rack plate can be guaranteed to be in a stable heat flow exchange state. If the opening rate is higher than the target value, the opening rate will increase. If the opening rate is lower than the target value, the opening rate will decrease. The actual structural dimensions are measured and calculated based on the unit area to set the A1 area. m2, W / m2, then:

[0145] ;

[0146] Calculate the opening ratio of the baffle member in area A1: , other areas are calculated in the same way to generate the opening ratio data of the baffle components.

[0147] S413: Based on the baffle member opening rate data and in combination with the strength target of the baffle member, the reinforcement density of the baffle member is calculated to obtain the partition opening rate configuration information.

[0148] Based on the baffle component opening rate data and the strength target of the baffle component, the reinforcement density of the baffle component is calculated. The reinforcement density calculation is based on the structural strength requirements and the reinforcement spacing is set. and opening rate The relationship between ,in is the safety factor, and this embodiment sets The safety factor is set based on the industrial structural design standard. Usually the safety factor is A larger safety factor ensures the strength requirement, but may increase the amount of material used, so choose As the optimized value, the Substitute:

[0149] ;

[0150] The reinforcement spacing of area A1 is calculated to be 1850 mm, and the partition opening ratio configuration information is obtained.

[0151] See also Figure 6 , the specific steps for obtaining structural adaptability test information are:

[0152] S511: Calling component material matching information, heat load zone plate replacement information, and zone opening ratio configuration information to obtain the overall thermal stress distribution, cyclic loading stability, and ventilation performance parameters of the adjusted fuel cell test rack, calculate the thermal stress peak, loading stability parameters, and air flow distribution characteristics of each area, and generate thermal stress and ventilation performance data of the fuel cell test rack;

[0153] Call the component material matching information, heat load zone plate replacement information and partition opening ratio configuration information to obtain the overall thermal stress distribution, cyclic loading stability and ventilation performance parameters of the adjusted fuel cell test frame. The thermal stress distribution is obtained through finite element analysis and the thermal stress peak value is set. The calculation basis is to use the maximum principal stress method to extract the local stress peak value and set the benchmark value. The bearing stress of the material is set according to the bearing capacity of the material under long-term loading conditions, and the maximum static load stress is taken. As a calculation benchmark, this benchmark value is set to ensure that the material will not approach its yield limit in actual working conditions, while still having sufficient safety margin under different working conditions. This benchmark value varies with the material type. For example, for 304 stainless steel, its maximum static load stress is MPa, then MPa, and for aluminum alloy 7075, its maximum static load stress is MPa, then MPa. The cyclic loading stability calculation is based on the cumulative stress change rate. The ventilation performance parameters are obtained by collecting data from the wind speed sensor. The flow field mean square error is used to calculate the airflow distribution uniformity. The thermal stress peak value, loading stability parameters, and air flow distribution characteristics of each area are calculated and stored in the database. Finally, the thermal stress and ventilation performance data of the fuel cell test rack are generated, as shown in Table 5.

[0154] Table 5 Thermal stress and ventilation performance data of fuel cell test rack

[0155]

[0156] As shown in Table 5 , the thermal stress and ventilation data of each area are used for subsequent fitness calculations.

[0157] S512: Based on the thermal stress and ventilation performance data of the fuel cell test rack, the calculation formula is:

[0158] ;

[0159] Calculate and obtain the suitability of the adjusted material and structural configuration to generate structural suitability data;

[0160] in, represents the structural fitness, Representative time The peak thermal stress at Representative time The material bearing stress at Representative time The air velocity at Representative time The target flow rate, represents the total time step;

[0161] Based on the thermal stress and ventilation performance data of the fuel cell test rack, the calculation formula is:

[0162] ;

[0163] The calculation obtains the adaptability of the adjusted material and structural configuration, where and The difference is used to measure the utilization rate of thermal stress on the material's bearing capacity, and the target benchmark is set as MPa. This value is set based on the material's fatigue limit and cyclic loading stability. Usually in mechanical structures, the fatigue limit is the maximum static load stress. to , here we take No more than MPa to ensure that there will be no cumulative damage during long-term use. If this range is exceeded, the material may cause crack propagation due to local overload, and the target flow rate may deviate. Used to measure the deviation of air flow rate, the target benchmark is set to m / s. This value is set with reference to the airflow uniformity standard of the fuel cell thermal management system to ensure that airflow velocity deviation does not affect the heat dissipation efficiency. Substitute the data of area A1 into the calculation:

[0164] ;

[0165] The structural fitness of the A1 region is calculated as , the remaining regions are calculated in the same way to generate structural fitness data.

[0166] S513: Based on the structural suitability data, the suitability standards are compared to determine whether the adjusted material and structural configurations meet the expected goals, and generate structural suitability test information.

[0167] Based on the structural fitness data, the fitness standards are compared to determine whether the adjusted material and structural configurations meet the expected goals. The fitness standards are set as The threshold is set based on the rationality of the structural force and the uniformity of the airflow distribution. Usually, in the process of thermal management optimization, the adaptation threshold is set at In the range, the larger the value, the lower the degree of structural optimization. As a criterion, it is ensured that the structure will not affect the overall performance due to excessive stress or excessive airflow deviation, such as in the A1 area. If the value is less than the set standard, the structural configuration is judged to meet the requirements, and finally the structural suitability test information is generated.

[0168] A fuel cell test rack design system is provided. The fuel cell test rack design system is used to execute the above-mentioned fuel cell test rack design method. The system includes:

[0169] The thermal load classification module obtains the usage records of the test frame components during a typical usage cycle, extracts the real-time temperature value, heat flux density value, and heat dissipation power per unit area value of each area's thermal load node, calculates the thermal load level value of each area, classifies the thermal load areas, and obtains the thermal load area classification results;

[0170] Based on the thermal load area classification results, the material matching module obtains the number of mechanical cycles, unit component strain range, and contact node continuous loading time of the load-bearing components in the fuel cell test rack during the service life. It calculates the required material strength grade for each component, compares it with the available material library, identifies the matching material for each component, and obtains component material matching information.

[0171] The heat load zone plate adjustment module calls component material matching information and heat load zone classification results to screen materials suitable for high heat load areas, perform material replacement, and calculate the adjusted component thickness based on component strength requirements to obtain heat load zone plate replacement information;

[0172] The opening adjustment module calculates the opening ratio required for each baffle component in each area based on the plate replacement information in the heat load zone and the heat dissipation target of each area. It also calculates the required reinforcement density of the baffle component based on the strength target of the baffle component to obtain the zone opening ratio configuration information.

[0173] The design effect analysis module calls on component material matching information, heat load zone plate replacement information and partition opening ratio configuration information to obtain the overall thermal stress distribution, cyclic loading stability and ventilation performance parameters of the adjusted fuel cell test frame, determine the compatibility of the adjusted material and structural configuration, and obtain structural adaptability test information.

[0174] The above are merely preferred embodiments of the present invention and do not limit the present invention in any other form. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A fuel cell test stand design method, characterized in that: The following steps are involved: S1: Obtain usage records of test frame components during a typical usage cycle, extract the real-time temperature value, heat flux density value, and heat dissipation power per unit area value of each area's heat load node, calculate the heat load level value of each area, perform heat load area classification, and obtain the heat load area classification results; S2: Based on the thermal load area classification results, obtain the number of mechanical cycles, unit component strain range, and contact node continuous loading time of the load-bearing components in the fuel cell test rack during the service life, calculate the material strength grade required for each component, compare with the available material library, identify the matching material for each component, and obtain component material matching information; S3: Calling the component material matching information and the heat load area classification result, screening the materials suitable for the high heat load area, performing material replacement, and calculating the adjusted component thickness based on the component strength requirements to obtain the plate replacement information for the heat load area; S4: Based on the plate replacement information of the heat load zone and in combination with the heat dissipation target of each zone, the required opening ratio of the baffle member of each zone is calculated. In combination with the strength target of the baffle member, the required reinforcement density of the baffle member is calculated to obtain the zone opening ratio configuration information; The steps for obtaining the heat load area classification result are specifically as follows: S111: Obtaining usage records of test frame components during a typical usage cycle, extracting real-time temperature values, heat flux density values, and heat dissipation power per unit area values ​​of heat load nodes in each region, organizing the acquired data in time series to form a temperature curve, heat flux density curve, and heat dissipation power curve distributed over time, establishing a data index, and generating a temperature, heat flux density, and heat dissipation power data series; S112: Based on the temperature, heat flux density, and heat dissipation power data sequence, a calculation formula is used: ； Calculate and obtain the heat load level value, and generate heat load level data; in, Represents the thermal load level value, Representative time The temperature value at Representative time The heat flux density value, represents the unit area, represents the total time step; S113: Based on the thermal load level data, calling a set thermal load determination threshold, performing thermal load area classification, screening areas where the thermal load level exceeds the threshold as high thermal load areas, and areas where the thermal load level is below the threshold as low thermal load areas, and generating a thermal load area classification result; The steps for obtaining the component material matching information are specifically as follows: S211: Based on the thermal load area classification result, obtaining the number of mechanical cycles, unit component strain range, and contact node continuous loading time of the load-bearing components in the fuel cell test rack during the service life, organizing the obtained data, dividing the data index by component, and calculating the cumulative stress change of each component to generate component stress change data; S212: Based on the component stress change data and the target thickness of each component, a calculation formula is used: ； Obtain the material strength grade required for the component through calculation and generate component material strength grade data; in, Represents the material strength grade required for the component, Representative time The number of mechanical cycles, Representative time The strain change of the internal components, Representative time The duration of loading of the inner contact nodes, represents the target thickness of the component, represents the total time step; S213: Based on the component material strength grade data, compare with the available material library, screen materials that meet the component material strength requirements, match the mechanical property parameters of the materials, and generate component material matching information.

2. The fuel cell test stand design method according to claim 1, characterized in that: The thermal load area classification results include high thermal load areas, low thermal load areas, and thermal load transition areas. The component material matching information specifically includes material strength grade, component fatigue tolerance grade, and material cyclic loading stability assessment value. The thermal load area plate replacement information includes high thermal load area replacement material type, low thermal load area maintenance material type, and structural plate thermal expansion adjustment strategy. The partitioned opening ratio configuration information specifically includes high thermal load area opening ratio setting value, low thermal load area opening ratio setting value, and airflow guide adjustment parameters.

3. The fuel cell test stand design method according to claim 1, characterized in that: The specific steps for obtaining the heat load zone plate replacement information are as follows: S311: Call the component material matching information and the heat load area classification result to calculate the temperature distribution of the fuel cell test frame structure plate in the high heat load area, identify the spatial coordinates of the temperature extreme point, and calculate the maximum temperature difference in the area using the formula: ； The heat flux density in the high heat load area is calculated; in, represents the heat flux density in the high heat load area, represents the thermal conductivity of the material, Represents the maximum temperature in the high heat load area, Represents the minimum temperature in the high heat load area, represents the thickness of the test frame structure plate; S312: Based on the heat flux density in the high heat load area, calling the material thermal expansion coefficient standard, screening materials that meet the requirements of the high heat load area, extracting the material name, thermal expansion coefficient, thermal conductivity and mechanical strength parameters, calculating the thermal strain of the material in the high heat load area, and obtaining the suitable material for the high heat load area; S313: Based on the high heat load area adaptive material and in combination with the component strength requirements, the adjusted component thickness is calculated, the plate configuration is optimized according to the adaptability of the heat load area, and the heat load area plate replacement information is obtained.

4. The fuel cell test rack design method according to claim 1, characterized in that: The steps for obtaining the partition opening ratio configuration information are specifically as follows: S411: Based on the plate replacement information of the heat load area, obtaining the unit area heat flux value, heat dissipation surface area, and gas convection rate ratio of each functional unit of the fuel cell test rack, sorting the data, and calculating the unit area heat dissipation capacity of each area to generate unit area heat dissipation capacity data; S412: Based on the heat dissipation capacity per unit area data and in combination with the heat dissipation target of each area, the formula is used: ； Obtaining the opening ratio of the baffle member in each area by calculation, and generating baffle member opening ratio data; in, represents the opening ratio of the baffle component, represents the heat flux per unit area, represents the heat dissipation surface area, represents the gas convection rate, Represents the heat dissipation target, represents the total surface area of ​​the baffle members; S413: Based on the baffle member opening rate data and in combination with the strength target of the baffle member, the reinforcement density of the baffle member is calculated to obtain the partition opening rate configuration information.

5. The fuel cell test stand design method according to claim 1, characterized in that: The method further comprises: S5: Recalling the component material matching information, the heat load zone plate replacement information, and the zone opening ratio configuration information, obtaining the overall thermal stress distribution, cyclic loading stability, and ventilation performance parameters of the adjusted fuel cell test stand, determining the compatibility of the adjusted material and structural configuration, and obtaining structural compatibility test information; The structural adaptability test information includes a thermal stress distribution coefficient, a cyclic loading stability parameter, and a ventilation performance evaluation value.

6. The fuel cell test rack design method according to claim 5, characterized in that: The steps for obtaining the structural adaptability test information are specifically as follows: S511: Calling the component material matching information, the heat load zone plate replacement information, and the zone opening ratio configuration information to obtain the overall thermal stress distribution, cyclic loading stability, and ventilation performance parameters of the adjusted fuel cell test rack, calculate the thermal stress peak, loading stability parameters, and air flow distribution characteristics of each area, and generate thermal stress and ventilation performance data of the fuel cell test rack; S512: Based on the thermal stress and ventilation performance data of the fuel cell test stand, a calculation formula is used: ； Calculate and obtain the suitability of the adjusted material and structural configuration to generate structural suitability data; in, represents the structural fitness, Representative time The peak thermal stress at Representative time The material bearing stress at Representative time The air velocity at Representative time The target flow rate, represents the total time step; S513: Based on the structural fitness data, the fitness standard is compared to determine whether the adjusted material and structural configurations meet the expected goals, and structural fitness test information is generated.

7. A fuel cell test rack design system, characterized in that: The fuel cell test rack design method according to any one of claims 1 to 6, wherein the system comprises: The thermal load classification module obtains the usage records of the test frame components in a typical usage cycle, calculates the thermal load level value of each area, classifies the thermal load areas, and obtains the thermal load area classification results; The material matching module calculates the material strength grade required for each component based on the heat load area classification result, identifies the matching material for each component, and obtains component material matching information; The heat load area plate adjustment module calls the component material matching information and the heat load area classification result, selects the material suitable for the high heat load area, replaces the material, and obtains the heat load area plate replacement information; The opening adjustment module calculates the opening ratio required for the baffle member of each area based on the plate replacement information of the heat load area and the heat dissipation target of each area, and obtains the partition opening ratio configuration information; The design effect analysis module calls the component material matching information, the heat load zone plate replacement information and the partition opening ratio configuration information to determine the compatibility of the adjusted material and structural configuration and obtain structural adaptability inspection information.

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