Environmental protection cabinet temperature rise modeling method and system based on multi-physical field coupling

Abstract

The present application belongs to the technical field of simulation analysis, and specifically relates to an environmental protection cabinet temperature rise modeling method and system based on multi-physical field coupling, which comprises the following steps: carrying out curved surface reconstruction on geometric structure data to generate a three-dimensional geometric curved surface model and construct a conformal grid model; collecting real-time current and voltage data, combining a preset temperature-dependent material attribute library, determining time-varying volume heat source density distribution, loading the heat source distribution to the conformal grid, setting coupling boundary conditions, establishing a fluid-solid-thermal multi-physical field coupling simulation model, and performing transient solution to obtain a steady-state fluid-thermal coupling simulation result; according to the comparison result of the simulation temperature steady-state value and the measured temperature, correcting the material thermal conductivity parameter to form a high-precision material attribute library; carrying out intrinsic orthogonal decomposition on the high-precision attribute library and the steady-state simulation result to obtain a temperature field base mode; and finally constructing a temperature rise prediction simulation model. The present application can improve the precision and efficiency of environmental protection cabinet temperature rise modeling.

Description

Technical Field

[0001] This invention belongs to the field of simulation analysis technology, and in particular relates to a method and system for modeling the temperature rise of environmental protection cabinets based on multi-physics coupling. Background Technology

[0002] As core electrical equipment in fields such as power, chemical industry, and industrial control, environmental protection cabinets are crucial carriers for key components such as circuit breakers and instrument transformers. Their operational stability directly affects industrial production safety and the reliable power supply of the power system. The electrical components inside the environmental protection cabinet generate Joule heat under load. Inadequate heat dissipation can easily lead to excessive temperature rise inside the cabinet, causing safety accidents such as insulation aging, electrical short circuits, and even fires and explosions. Therefore, accurate temperature rise simulation modeling to predict the temperature field and provide risk warnings is a key technical requirement for ensuring the safe and efficient operation of environmental protection cabinets.

[0003] Existing environmental protection cabinet temperature rise simulation technologies generally employ simplified geometric modeling, empirical heat source estimation, and single-physics field solution modes, which have several technical bottlenecks: First, traditional mesh models cannot accurately reproduce the complex cavity structure and component layout inside the environmental protection cabinet, resulting in large data interaction errors at the fluid-solid interface and affecting simulation accuracy; second, time-varying heat source density relies on empirical formulas rather than real-time electrical parameters, resulting in low matching with actual heating conditions and failing to accurately reflect the dynamic temperature rise under load changes; third, single-physics field solutions ignore the coupling effect between the flow field and the temperature field, making it difficult to capture the temperature rise law under the synergistic effect of multiple fluid-solid-thermal physics fields; fourth, existing technologies have long modeling cycles and low solution efficiency, making it difficult to meet the engineering application requirements for real-time monitoring and early warning of environmental protection cabinets. Therefore, a high-precision and high-efficiency temperature rise modeling scheme is urgently needed. Summary of the Invention

[0004] This invention provides a method and system for modeling the temperature rise of environmental protection cabinets based on multi-physics coupling. By constructing an accurate simulation model through multi-physics coupling, and combining it with measured material parameters for correction, a prediction model is built through intrinsic orthogonal decomposition. This improves the accuracy and efficiency of environmental protection cabinet temperature rise modeling, and enables real-time accurate prediction of temperature rise, adapting to actual monitoring and early warning needs.

[0005] To achieve the above objectives, the present invention provides a method for modeling the temperature rise of environmental protection cabinets based on multi-physics coupling, comprising the following steps:

[0006] S1. Reconstruct the surface of the geometric structure data of the environmental protection cabinet to obtain the three-dimensional geometric surface model of the environmental protection cabinet, and extract the fluid domain from the three-dimensional geometric surface model to obtain the conformal mesh model of the environmental protection cabinet.

[0007] S2. Collect the real-time current and voltage values ​​of the heating devices inside the environmental protection cabinet, and combine them with the preset temperature-dependent material property library to determine the time-varying volumetric heat source density distribution of the heating devices.

[0008] S3. The time-varying volumetric heat source density distribution is applied as a volume load to the solid region of the conformal mesh model, and the coupling boundary conditions between the solid region and the fluid region in the conformal mesh model are set to construct a fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet.

[0009] S4. The fluid-solid-thermal multiphysics coupling simulation model is solved transiently. During the solution process, the temperature distribution in the solid region and the flow field distribution in the fluid region are updated alternately, and the temperature value and heat flow value are exchanged at the interface to obtain the steady-state fluid-thermal coupling simulation results of the environmental protection cabinet.

[0010] S5. Based on the comparison between the steady-state temperature value and the measured temperature value in the environmental protection cabinet in the steady-state flow-heat coupling simulation results, the material thermal conductivity parameters in the conformal mesh model are corrected to obtain a high-precision material property library for the environmental protection cabinet.

[0011] S6. Perform intrinsic orthogonal decomposition on the high-precision material property library and steady-state flow-heat coupling simulation results to obtain the temperature field fundamental mode of the environmental protection cabinet. Based on the mapping relationship between the temperature field fundamental mode and the real-time current and voltage values, construct a temperature rise prediction simulation model for the environmental protection cabinet.

[0012] Preferably, in S1, the process of obtaining the conformal mesh model of the environmental protection cabinet includes:

[0013] The original point cloud data of the internal cavity and external shell of the environmental protection cabinet are obtained, and the original point cloud data are registered and fused to obtain the closed surface point cloud set of the environmental protection cabinet.

[0014] The closed surface point cloud is triangularly meshed, and the meshed triangular mesh is smoothed to obtain the initial three-dimensional geometric surface model of the environmental protection cabinet.

[0015] Identify the closed surface region representing the internal cavity of the environmental protection cabinet in the initial three-dimensional geometric surface model, and mark the fluid domain boundary in the initial three-dimensional geometric surface model according to the relative positional relationship between the closed surface region and the outer shell surface in the environmental protection cabinet.

[0016] Based on the fluid domain boundary, the fluid domain surface model of the environmental protection cabinet is extracted from the initial three-dimensional geometric surface model;

[0017] By integrating the fluid domain surface model and the solid domain surface model of the environmental protection cabinet, a composite geometric model of the environmental protection cabinet is obtained.

[0018] The fluid domain part of the composite geometric model is discretized into an unstructured hexahedral mesh, the solid domain part of the composite geometric model is discretized into a tetrahedral mesh, and a conformal mesh interface with completely corresponding nodes is generated at the interface between the fluid domain and the solid domain to obtain the conformal mesh model of the environmental protection cabinet.

[0019] Preferably, in S2, the process of determining the time-varying volumetric heat source density distribution of the heating device includes:

[0020] Obtain the original current sampling sequence and original voltage sampling sequence of the heating device inside the environmental protection cabinet during the monitoring period;

[0021] The original current sampling sequence and the original voltage sampling sequence are timestamped to obtain the synchronous current timing data and synchronous voltage timing data of the environmental protection cabinet;

[0022] Based on the material identifier of the heating device, the corresponding resistivity-temperature relationship data is extracted from a preset temperature-dependent material property library;

[0023] The estimated temperature field distribution data of the environmental protection cabinet at the initial moment is obtained, and the temperature value of the spatial location of the heating device is extracted from the estimated temperature field distribution data as the current temperature input of the environmental protection cabinet.

[0024] Linear interpolation is performed on the current temperature input and resistivity-temperature relationship data to obtain the current resistivity of the heating device, and the equivalent resistance of the heating device is determined by combining the geometric parameters of the heating device.

[0025] Based on the synchronous current timing data and equivalent resistance, the instantaneous heating power timing data of the heating device is determined, and based on the geometric volume of the heating device, the instantaneous heating power timing data is converted into the time-varying volumetric heat source density distribution of the heating device.

[0026] Preferably, in S3, the time-varying volumetric heat source density distribution is applied as a volume load to the solid region of the conformal mesh model, specifically including:

[0027] Read the grid cell identifier information and corresponding geometric center coordinates belonging to the solid region in the conformal mesh model to obtain the solid cell index table of the environmental protection cabinet;

[0028] Traverse the grid cells in the solid element index table, determine the corresponding heating device based on the geometric center coordinates, and assign the time-varying volume heat source density distribution of the heating device to the grid cell to obtain the solid element-heat source density mapping relationship of the environmental protection cabinet.

[0029] Based on the solid element-heat source density mapping relationship, the heat source density of the solid region is written into the data structure of the conformal mesh model in the form of a scalar field, thus obtaining the conformal mesh model of the heat source load of the environmental protection cabinet.

[0030] Preferably, in S3, the coupling boundary conditions between the solid region and the fluid region in the conformal mesh model are set to construct a fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet, specifically including:

[0031] The grid nodes at the interface between the solid and fluid regions are extracted from the conformal grid model of the heat source load to obtain the boundary nodes of the environmental protection cabinet, and a topological association record between the adjacent regions on the solid side and the adjacent regions on the fluid side is established for the boundary nodes.

[0032] Based on the topology association record, a data exchange channel is defined on the boundary node, and the configuration information of the data exchange channel is bound to the identifier of the boundary node to obtain the coupling boundary conditions of the environmental protection cabinet.

[0033] By integrating the coupled boundary conditions and the conformal mesh model of the heat source load, a fluid-solid-thermal multiphysics coupled simulation model of the environmental protection cabinet is obtained.

[0034] Preferably, in S4, the process of obtaining the steady-state flow-heat coupling simulation results of the environmental protection cabinet includes:

[0035] Set the current time step and initialize the current time to zero. Within the current time step, execute the following iterative process;

[0036] Based on the solid region temperature distribution of the previous iteration step, the flow field of the fluid region is calculated to obtain the fluid region flow field distribution of the current iteration step, and the fluid side temperature value and fluid side heat flux value at the interface node are extracted from the fluid region flow field distribution.

[0037] Using the fluid-side temperature and fluid-side heat flow as boundary conditions, the temperature field of the solid region is solved to obtain the solid region temperature distribution in the current iteration step, and the solid-side temperature and solid-side heat flow values ​​at the interface nodes are extracted from the solid region temperature distribution.

[0038] Calculate the coupling residual of the current iteration step based on the solid-side temperature value, fluid-side temperature value, solid-side heat flow value, and fluid-side heat flow value;

[0039] The coupling residuals are compared and analyzed with the temperature convergence threshold and heat flow convergence threshold of the environmental protection cabinet to obtain the steady-state flow-heat coupling simulation results of the environmental protection cabinet.

[0040] Preferably, the formula for calculating the coupling residual is:

[0041] ;

[0042] in, Indicates coupling residuals, This represents the solid-side temperature value at the i-th interface node in the current iteration step, where N is the number of interface nodes. This represents the fluid-side temperature value at the i-th interface node in the current iteration step. This represents the solid-side heat flux value at the i-th interface node in the current iteration step. This represents the fluid-side heat flux value at the i-th interface node in the current iteration step. This indicates the normalized reference value for the temperature of the eco-friendly cabinet. This indicates the normalized reference value of the heat flow of the environmental protection cabinet. This represents the preset temperature deviation weighting coefficient. This represents the preset heat flow deviation weighting coefficient, and .

[0043] Preferably, in S5, the process of obtaining the high-precision material property library of the environmental protection cabinet includes:

[0044] Simulated temperature data was extracted from the steady-state fluid-thermal coupling simulation results, and measured temperature data at corresponding locations inside the environmental protection cabinet were collected.

[0045] The simulated temperature data and the measured temperature data are compared point by point to obtain the temperature deviation of the environmental protection cabinet. The temperature deviation is then spatially interpolated to obtain the temperature deviation distribution map of the environmental protection cabinet.

[0046] Read the initial thermal conductivity parameters of the solid material region in the conformal mesh model, and identify the area to be corrected in the environmental protection cabinet based on the temperature deviation distribution map;

[0047] Based on the temperature deviation, the initial thermal conductivity parameters of the region to be corrected are iteratively updated to obtain the corrected thermal conductivity parameters of the region to be corrected.

[0048] The corrected thermal conductivity parameters are integrated and packaged to obtain a high-precision material property library for environmental protection cabinets.

[0049] Preferably, in S6, the process of constructing a temperature rise prediction simulation model for the environmental protection cabinet includes:

[0050] Extract the transient temperature field snapshot sequence from the steady-state flow-heat coupling simulation results under different load conditions, and assemble the transient temperature field snapshot sequence into the temperature field snapshot matrix of the environmental protection cabinet;

[0051] The thermal property parameters of solid material regions in the high-precision material property library are associated and bound with the temperature field snapshot matrix to obtain the temperature field snapshot dataset of the environmental protection cabinet.

[0052] The temperature field snapshot dataset is centered to obtain the temperature field fluctuation dataset of the environmental protection cabinet.

[0053] Eigenvalue decomposition was performed on the temperature field fluctuation dataset to obtain the temperature field fundamental modes of the environmental protection cabinet;

[0054] Obtain the real-time current value sequence and real-time voltage value sequence corresponding to the temperature field snapshot dataset, and normalize the real-time current value sequence and real-time voltage value sequence to obtain the electrical parameter feature vector of the environmental protection cabinet;

[0055] Based on the correspondence between the temperature field fundamental modes and the eigenvectors of electrical parameters, a modal coefficient-electrical parameter mapping matrix is ​​constructed for the environmental protection cabinet;

[0056] By combining and encapsulating the temperature field fundamental modes and the mode coefficient-electrical parameter mapping matrix, a temperature rise prediction simulation model for the environmental protection cabinet is obtained.

[0057] A multi-physics coupling-based environmental protection cabinet temperature rise modeling system, used to implement the above method, includes:

[0058] The conformal mesh model construction module is used to reconstruct the surface of the geometric structure data of the environmental protection cabinet to obtain the three-dimensional geometric surface model of the environmental protection cabinet, and to extract the fluid domain from the three-dimensional geometric surface model to obtain the conformal mesh model of the environmental protection cabinet.

[0059] The heat source density determination module is used to collect the real-time current and voltage values ​​of the heating devices inside the environmental protection cabinet, and combine them with a preset temperature-dependent material property library to determine the time-varying volumetric heat source density distribution of the heating devices.

[0060] The simulation model construction module is used to load the time-varying volumetric heat source density distribution as a volume load onto the solid region of the conformal mesh model, and to set the coupling boundary conditions between the solid region and the fluid region in the conformal mesh model to construct a fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet.

[0061] The simulation model solving module is used to perform transient solutions to the fluid-solid-thermal multiphysics coupling simulation model. During the solution process, the temperature distribution in the solid region and the flow field distribution in the fluid region are updated alternately, and the temperature value and heat flow value are exchanged at the interface to obtain the steady-state fluid-thermal coupling simulation results of the environmental protection cabinet.

[0062] The material property library generation module is used to correct the material thermal conductivity parameters in the conformal mesh model based on the comparison between the steady-state temperature value in the steady-state flow-heat coupling simulation results and the measured temperature value in the environmental protection cabinet, so as to obtain a high-precision material property library for the environmental protection cabinet.

[0063] The temperature rise prediction model construction module is used to perform intrinsic orthogonal decomposition on the high-precision material property library and steady-state flow-heat coupling simulation results to obtain the temperature field fundamental mode of the environmental protection cabinet. Based on the mapping relationship between the temperature field fundamental mode and the real-time current and voltage values, the temperature rise prediction simulation model of the environmental protection cabinet is constructed.

[0064] The present invention has the following beneficial effects:

[0065] This invention generates a conformal mesh model by reconstructing the surface of the environmental protection cabinet's geometry and extracting the fluid domain. Combined with a temperature-dependent material property library to determine the time-varying volumetric heat source density distribution, it constructs an accurate fluid-solid-thermal multiphysics coupled simulation model. In the transient solution, the temperature and flow field distribution of the solid and liquid regions are updated alternately. Furthermore, the material thermal conductivity parameters are corrected using measured temperature values, and a high-precision material property library is created. The entire process from model construction and parameter determination to solution correction is technically optimized, significantly improving the accuracy of environmental protection cabinet temperature rise modeling. This allows the modeling results to better reflect the actual temperature rise variation of the environmental protection cabinet, effectively ensuring the scientific validity and reliability of the temperature rise modeling.

[0066] This invention obtains the fundamental modes of the temperature field by performing intrinsic orthogonal decomposition on a high-precision material property library and steady-state fluid-thermal coupling simulation results. Combined with the mapping relationship between these modes and real-time electrical parameters, a temperature rise prediction simulation model is constructed. By using modal analysis and parameter mapping, the calculation process for temperature rise prediction is simplified, improving the efficiency of temperature rise modeling and prediction for environmental protection cabinets. It can quickly respond to real-time changes in the electrical parameters of heating devices, achieving efficient modeling and accurate prediction of temperature rise in environmental protection cabinets, and providing efficient technical support for temperature rise control and performance optimization of environmental protection cabinets. Attached Figure Description

[0067] Figure 1 This is a flowchart illustrating the temperature rise modeling method for environmental protection cabinets based on multi-physics coupling according to the present invention.

[0068] Figure 2 This is a functional module diagram of the environmental protection cabinet temperature rise modeling system based on multi-physics coupling of the present invention;

[0069] Figure 3 This is a temperature change curve under operating condition 1 during the verification process of this invention;

[0070] Figure 4 This is a graph showing the change in coupling residuals under operating condition 1 during the verification process of this invention.

[0071] Figure 5 This is a temperature change curve under operating condition 2 during the verification process of this invention;

[0072] Figure 6 This is a curve showing the change of coupling residuals under operating condition 2 during the verification process of this invention. Detailed Implementation

[0073] Example 1: As Figure 1 As shown, the method for modeling the temperature rise of environmental protection cabinets based on multiphysics coupling includes the following steps:

[0074] S1. Reconstruct the surface of the geometric structure data of the environmental protection cabinet to obtain the three-dimensional geometric surface model of the environmental protection cabinet, and extract the fluid domain from the three-dimensional geometric surface model to obtain the conformal mesh model of the environmental protection cabinet.

[0075] S2. Collect the real-time current and voltage values ​​of the heating devices inside the environmental protection cabinet, and combine them with the preset temperature-dependent material property library to determine the time-varying volumetric heat source density distribution of the heating devices.

[0076] S3. The time-varying volumetric heat source density distribution is applied as a volume load to the solid region of the conformal mesh model, and the coupling boundary conditions between the solid region and the fluid region in the conformal mesh model are set to construct a fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet.

[0077] S4. The fluid-solid-thermal multiphysics coupling simulation model is solved transiently. During the solution process, the temperature distribution in the solid region and the flow field distribution in the fluid region are updated alternately, and the temperature value and heat flow value are exchanged at the interface to obtain the steady-state fluid-thermal coupling simulation results of the environmental protection cabinet.

[0078] S5. Based on the comparison between the steady-state temperature value and the measured temperature value in the environmental protection cabinet in the steady-state flow-heat coupling simulation results, the material thermal conductivity parameters in the conformal mesh model are corrected to obtain a high-precision material property library for the environmental protection cabinet.

[0079] S6. Perform intrinsic orthogonal decomposition on the high-precision material property library and steady-state flow-heat coupling simulation results to obtain the temperature field fundamental mode of the environmental protection cabinet. Based on the mapping relationship between the temperature field fundamental mode and the real-time current and voltage values, construct a temperature rise prediction simulation model for the environmental protection cabinet.

[0080] In S1, the conformal mesh model of the environmental protection cabinet is obtained, including:

[0081] The original point cloud data of the internal cavity and external shell of the environmental protection cabinet are obtained, and the original point cloud data are registered and fused to obtain the closed surface point cloud set of the environmental protection cabinet.

[0082] The closed surface point cloud is triangularly meshed, and the meshed triangular mesh is smoothed to obtain the initial three-dimensional geometric surface model of the environmental protection cabinet.

[0083] Identify the closed surface region representing the internal cavity of the environmental protection cabinet in the initial three-dimensional geometric surface model, and mark the fluid domain boundary in the initial three-dimensional geometric surface model according to the relative positional relationship between the closed surface region and the outer shell surface in the environmental protection cabinet.

[0084] Based on the fluid domain boundary, the fluid domain surface model of the environmental protection cabinet is extracted from the initial three-dimensional geometric surface model;

[0085] By integrating the fluid domain surface model and the solid domain surface model of the environmental protection cabinet, a composite geometric model of the environmental protection cabinet is obtained.

[0086] The fluid domain part of the composite geometric model is discretized into an unstructured hexahedral mesh, the solid domain part of the composite geometric model is discretized into a tetrahedral mesh, and a conformal mesh interface with completely corresponding nodes is generated at the interface between the fluid domain and the solid domain to obtain the conformal mesh model of the environmental protection cabinet.

[0087] The original point cloud data of the internal cavity and external shell of the environmental protection cabinet are collected by a 3D scanning device. The point cloud data of the internal cavity and the external shell obtained from different acquisition perspectives are imported into the point cloud processing environment. Using the feature points of the external shell of the environmental protection cabinet as the registration reference, the point cloud data of the internal cavity and the point cloud data of the external shell are spatially aligned. Then, all the aligned point cloud data are fused and stitched together, and redundant point cloud data in overlapping areas are removed to finally obtain the closed curved surface point cloud set of the environmental protection cabinet.

[0088] Based on the triangular meshing rules, points within the closed surface point cloud are used as mesh vertices. Adjacent vertices are connected sequentially to form continuous triangular patches. The entire closed surface point cloud is then subjected to triangular meshing. A vertex smoothing algorithm is then used to adjust the position of all vertices of the triangular mesh after meshing, eliminating sharp protrusions and depressions on the mesh surface. This ensures that the size and shape of the triangular patches are evenly distributed, ultimately yielding the initial three-dimensional geometric surface model of the environmental protection cabinet.

[0089] Based on the structural design drawings of the environmental protection cabinet, a closed region without openings, formed by continuous curved surfaces, is identified in the initial three-dimensional geometric surface model. This closed region is the closed curved surface region representing the internal cavity of the environmental protection cabinet. Then, by comparing spatial coordinates, the relative position of this closed curved surface region and the curved surface of the outer shell of the environmental protection cabinet in three-dimensional space is determined. Based on this relative position, the spatial boundary separating the internal cavity and the outer shell is delineated on the initial three-dimensional geometric surface model. This spatial boundary is marked as the fluid domain boundary in the initial three-dimensional geometric surface model.

[0090] Using the marked fluid domain boundary as the extraction range, all surface structures enclosed by the boundary are segmented in the initial three-dimensional geometric surface model. The integrity of the segmented surface structures is checked to ensure that the surface structures are undamaged and without missing parts. The surface structure that passes the check is directly identified as the fluid domain surface model of the environmental protection cabinet.

[0091] The extracted fluid domain surface model is integrated with the remaining shell-like surface structure in the initial three-dimensional geometric surface model of the environmental protection cabinet. This shell-like surface structure is the solid domain surface model of the environmental protection cabinet. The spatial positions of the fluid domain surface model and the solid domain surface model are calibrated in three-dimensional space to ensure that their relative positions are completely consistent with the actual structure of the environmental protection cabinet. After calibration, the two surface models are combined to form a complete composite geometric model of the environmental protection cabinet.

[0092] For the fluid domain portion of the composite geometric model, an unstructured hexahedral mesh discretization method is adopted to generate size-adapted hexahedral mesh elements in the three-dimensional space of the fluid domain surface model, thus completing the mesh discretization of the fluid domain. For the solid domain portion of the composite geometric model, a tetrahedral mesh discretization method is adopted to generate size-adapted tetrahedral mesh elements in the three-dimensional space of the solid domain surface model, thus completing the mesh discretization of the solid domain. At the interface between the fluid and solid domains, the mesh nodes of the fluid domain and the mesh nodes of the solid domain are made to completely coincide in spatial coordinates, forming a conformal mesh interface with completely corresponding nodes. The overall model with the discretized conformal mesh interface is determined as the conformal mesh model of the environmental protection cabinet.

[0093] Through standardized point cloud processing, mesh generation, and surface extraction operations, a conformal mesh model of the environmental protection cabinet was accurately constructed, achieving precise division between the fluid and solid domains. Furthermore, a conformal mesh interface with completely corresponding nodes was formed at the interface, ensuring a high degree of fit between the mesh model and the actual geometry of the environmental protection cabinet. Simultaneously, the fluid and solid domains adopted an adaptive mesh discretization method, making the mesh model structure more reasonable. This laid a solid geometric model foundation for subsequent boundary data exchange and accurate solution in multiphysics coupling simulations, effectively avoiding simulation result errors caused by mesh model deviations.

[0094] In S2, the time-varying volumetric heat source density distribution of the heating device is determined, including:

[0095] Obtain the original current sampling sequence and original voltage sampling sequence of the heating device inside the environmental protection cabinet during the monitoring period;

[0096] The original current sampling sequence and the original voltage sampling sequence are timestamped to obtain the synchronous current timing data and synchronous voltage timing data of the environmental protection cabinet;

[0097] Based on the material identifier of the heating device, the corresponding resistivity-temperature relationship data is extracted from a preset temperature-dependent material property library;

[0098] The estimated temperature field distribution data of the environmental protection cabinet at the initial moment is obtained, and the temperature value of the spatial location of the heating device is extracted from the estimated temperature field distribution data as the current temperature input of the environmental protection cabinet.

[0099] Linear interpolation is performed on the current temperature input and resistivity-temperature relationship data to obtain the current resistivity of the heating device, and the equivalent resistance of the heating device is determined by combining the geometric parameters of the heating device.

[0100] Based on the synchronous current timing data and equivalent resistance, the instantaneous heating power timing data of the heating device is determined, and based on the geometric volume of the heating device, the instantaneous heating power timing data is converted into the time-varying volumetric heat source density distribution of the heating device.

[0101] By deploying current and voltage sampling elements in the heating device circuit inside the environmental protection cabinet, current and voltage data during the operation of the heating device are continuously collected at set sampling intervals. All current data collected in chronological order are organized into the original current sampling sequence of the heating device inside the environmental protection cabinet, and all voltage data collected in chronological order are organized into the original voltage sampling sequence of the heating device inside the environmental protection cabinet.

[0102] Extract the acquisition timestamp corresponding to each data point in the original current sampling sequence and the original voltage sampling sequence. Based on the acquisition timestamp, remove redundant data points with mismatched timestamps in the two sequences. Data points with consistent timestamps are integrated one by one. The integrated current data are rearranged in time order to form synchronous current timing data, and the integrated voltage data are rearranged in time order to form synchronous voltage timing data.

[0103] In a pre-defined temperature-dependent material property library, a unique material identifier is configured for heating devices made of different materials. Each material identifier corresponds to the storage of data on the resistivity of the material as a function of temperature. Based on the actual material identifier of the heating device inside the environmental protection cabinet, a precise search is performed in this property library to directly retrieve the resistivity-temperature relationship data that matches the material identifier.

[0104] The initial simulation calculation of the environmental protection cabinet temperature rise simulation is used to obtain the temperature data of each position in the overall space of the environmental protection cabinet at the initial moment. This data is the estimated temperature field distribution data of the environmental protection cabinet at the initial moment. According to the actual spatial position of the heating device in the environmental protection cabinet, the temperature value corresponding to the position is selected from the estimated temperature field distribution data and used as the current temperature input of the environmental protection cabinet.

[0105] The current temperature input is substituted into the extracted resistivity-temperature relationship data. Linear interpolation is performed within the numerical range of the resistivity-temperature relationship data to obtain the resistivity value corresponding to the current temperature input. This value is the current resistivity of the heating device. Combined with the actual length, cross-sectional area and other geometric parameters of the heating device, the current resistivity and geometric parameters are combined according to the resistance calculation logic to calculate the equivalent resistance of the heating device.

[0106] Based on each current value in the synchronous current time series data, combined with the determined equivalent resistance of the heating device, the heating power value corresponding to each time point is calculated sequentially according to the power calculation logic. The heating power values ​​of all time points are arranged in chronological order to form the instantaneous heating power time series data of the heating device. The actual geometric volume of the heating device is measured and determined in advance. Each power value in the instantaneous heating power time series data is converted with the geometric volume. All the converted data are organized in chronological order to finally form the time-varying volume heat source density distribution of the heating device.

[0107] By accurately collecting and synchronizing the time-series data of electrical parameters of the heating device, and combining it with a temperature-dependent material property library, dynamic matching of resistivity was achieved. Then, the equivalent resistance was determined by combining linear interpolation and geometric parameters. Finally, the accurate conversion from heating power to time-varying volumetric heat source density distribution was completed. The entire process achieved deep integration of electrical parameters, temperature parameters and structural parameters, so that the determined time-varying volumetric heat source density distribution can accurately reflect the actual heating state of the heating device. This provides a realistic heat source load basis for subsequent multiphysics coupling simulation and effectively improves the input accuracy of the simulation model.

[0108] In S3, the time-varying volumetric heat source density distribution is applied as a volume load to the solid region of the conformal mesh model, specifically including:

[0109] Read the grid cell identifier information and corresponding geometric center coordinates belonging to the solid region in the conformal mesh model to obtain the solid cell index table of the environmental protection cabinet;

[0110] Traverse the grid cells in the solid element index table, determine the corresponding heating device based on the geometric center coordinates, and assign the time-varying volume heat source density distribution of the heating device to the grid cell to obtain the solid element-heat source density mapping relationship of the environmental protection cabinet.

[0111] Based on the solid element-heat source density mapping relationship, the heat source density of the solid region is written into the data structure of the conformal mesh model in the form of a scalar field, thus obtaining the conformal mesh model of the heat source load of the environmental protection cabinet.

[0112] By setting coupling boundary conditions between the solid region and the fluid region in the conformal mesh model, a fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet is constructed, specifically including:

[0113] The grid nodes at the interface between the solid and fluid regions are extracted from the conformal grid model of the heat source load to obtain the boundary nodes of the environmental protection cabinet, and a topological association record between the adjacent regions on the solid side and the adjacent regions on the fluid side is established for the boundary nodes.

[0114] Based on the topology association record, a data exchange channel is defined on the boundary node, and the configuration information of the data exchange channel is bound to the identifier of the boundary node to obtain the coupling boundary conditions of the environmental protection cabinet.

[0115] By integrating the coupled boundary conditions and the conformal mesh model of the heat source load, a fluid-solid-thermal multiphysics coupled simulation model of the environmental protection cabinet is obtained.

[0116] From the basic data of the conformal mesh model of the environmental protection cabinet, all mesh units belonging to the solid area are accurately selected, the unique identification information of each mesh unit is extracted, and the geometric center coordinates of each mesh unit are calculated. The identification information of each mesh unit and the corresponding geometric center coordinates are integrated one by one and organized into a solid unit index table of the environmental protection cabinet according to a unified format.

[0117] Following the order of the solid element index table, each grid element in the table is traversed and checked sequentially. Based on the geometric center coordinates of each grid element, the corresponding heating device is matched in three-dimensional space. After clarifying the correspondence between the grid element and the heating device, the time-varying volumetric heat source density distribution of the corresponding heating device is completely assigned to the grid element. The association information between all grid elements and their corresponding heat source density distributions is compiled and summarized to obtain the solid element-heat source density mapping relationship of the environmental protection cabinet.

[0118] Based on the solid element-heat source density mapping relationship, the heat source density values ​​corresponding to each grid element in the solid region are extracted. These values ​​are then processed into a scalar field for data structuring. In accordance with the data structure specifications of the conformal grid model, the processed scalar field data is completely written into the corresponding data storage area of ​​the model. The model after the data writing is completed is the conformal grid model of the heat source load of the environmental protection cabinet.

[0119] From the conformal mesh model of the heat source load of the environmental protection cabinet, the interface between the solid region and the fluid region is identified. All mesh nodes on the interface are extracted and organized into the boundary nodes of the environmental protection cabinet. For each boundary node, the adjacent mesh cell regions on the solid region side and the adjacent mesh cell regions on the fluid region side are found. The spatial association information between the boundary node and the adjacent regions on both sides is recorded to form a complete topological association record.

[0120] Based on the topological association records of the boundary nodes, a dedicated data exchange channel is defined on each boundary node. This channel is used to realize the bidirectional transmission of temperature and heat flow data between the solid region and the fluid region. The transmission rules, data interaction frequency and other configuration information of the data exchange channel are sorted out, and these configuration information are bound to the unique identifier of the corresponding boundary node. The binding information corresponding to all boundary nodes is integrated to form the coupling boundary conditions of the environmental protection cabinet.

[0121] The determined coupling boundary conditions of the environmental protection cabinet are used as the basic constraints and are fully integrated with the existing conformal mesh model of the heat source load. The relevant data of the coupling boundary conditions are incorporated into the overall data structure of the conformal mesh model of the heat source load, so that the model can follow the boundary conditions to realize the multiphysics data interaction between the solid and fluid regions. The model formed after integration is the fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet.

[0122] By standardizing grid cell data extraction, heat source density matching assignment, and scalar field writing, the time-varying volumetric heat source density distribution was accurately loaded onto the solid region of the conformal grid model. Simultaneously, by extracting boundary nodes, establishing topological association records, and defining data exchange channels, coupled boundary conditions that fit the model structure were constructed. The final fluid-solid-thermal multiphysics coupled simulation model not only has a realistic heat source load foundation but also achieves accurate data interaction constraints in the solid-fluid region. This provides a structurally complete and parameter-accurate simulation model foundation for subsequent transient solutions of multiphysics coupling, effectively ensuring the timeliness and accuracy of data interaction during the solution process.

[0123] In S4, the steady-state flow-thermal coupling simulation results of the environmental protection cabinet are obtained, including:

[0124] Set the current time step and initialize the current time to zero. Within the current time step, execute the following iterative process;

[0125] Based on the solid region temperature distribution of the previous iteration step, the flow field of the fluid region is calculated to obtain the fluid region flow field distribution of the current iteration step, and the fluid side temperature value and fluid side heat flux value at the interface node are extracted from the fluid region flow field distribution.

[0126] Using the fluid-side temperature and fluid-side heat flow as boundary conditions, the temperature field of the solid region is solved to obtain the solid region temperature distribution in the current iteration step, and the solid-side temperature and solid-side heat flow values ​​at the interface nodes are extracted from the solid region temperature distribution.

[0127] Calculate the coupling residual of the current iteration step based on the solid-side temperature value, fluid-side temperature value, solid-side heat flow value, and fluid-side heat flow value;

[0128] The coupling residuals are compared and analyzed with the temperature convergence threshold and heat flow convergence threshold of the environmental protection cabinet to obtain the steady-state flow-heat coupling simulation results of the environmental protection cabinet.

[0129] The formula for calculating the coupling residual is:

[0130] ;

[0131] in, Indicates coupling residuals, This represents the solid-side temperature value at the i-th interface node in the current iteration step, where N is the number of interface nodes. This represents the fluid-side temperature value at the i-th interface node in the current iteration step. This represents the solid-side heat flux value at the i-th interface node in the current iteration step. This represents the fluid-side heat flux value at the i-th interface node in the current iteration step. This indicates the normalized reference value for the temperature of the eco-friendly cabinet. This indicates the normalized reference value of the heat flow of the environmental protection cabinet. This represents the preset temperature deviation weighting coefficient. This represents the preset heat flow deviation weighting coefficient, and .

[0132] A fixed time step value is set for the fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet. The current time of the model solution is initialized to zero. Within the fixed current time step range, the iterative solution process of the flow field and temperature field is continuously executed until the convergence requirement is met.

[0133] The solid region temperature distribution obtained from the previous iteration is used as the basis for the fluid region solution. The fluid region is completely solved according to the multi-physics field coupled flow field solution logic to obtain the flow field distribution data of the fluid region under the current iteration step. The fluid side temperature value and fluid side heat flow value corresponding to the interface node position are accurately selected from the flow field distribution data to complete the extraction and temporary storage of this type of data.

[0134] The extracted fluid-side temperature and fluid-side heat flow values ​​are used as boundary constraints for the temperature field solution of the solid region. The solid region is completely solved according to the temperature field solution logic of multi-physics coupling to obtain the temperature distribution data of the solid region in the current iteration step. The solid-side temperature and solid-side heat flow values ​​corresponding to the interface node positions are accurately selected from the temperature distribution data to complete the extraction and temporary storage of this type of data.

[0135] The solid-side temperature value, fluid-side temperature value, solid-side heat flow value, and fluid-side heat flow value extracted in the current iteration step are integrated and calculated according to the calculation logic of the coupling residual to obtain the coupling residual value corresponding to the current iteration step. This value directly reflects the degree of matching of physical quantities at the solid-fluid interface.

[0136] In the current iteration step, the 1st The solid-side temperature values ​​at each interface node are extracted from the temperature distribution of the solid region after temperature field calculation; in the current iteration step, the... The fluid-side temperature values ​​at each interface node are extracted from the flow field distribution of the fluid region after flow field calculation; in the current iteration step, the... The solid-side heat flux values ​​at each interface node are extracted from the temperature distribution of the solid region after temperature field calculation; in the current iteration step, the... The fluid-side heat flux values ​​at each interface node are extracted from the flow field distribution of the fluid region after flow field calculation; the temperature normalization reference value of the environmental protection cabinet is a fixed value (dimensioned in °C for calculation) pre-set for normalizing temperature-related data during the environmental protection cabinet temperature rise modeling process; the heat flux normalization reference value of the environmental protection cabinet is a fixed value (dimensioned in W / m³) pre-set for normalizing heat flux-related data during the environmental protection cabinet temperature rise modeling process. 2 (for calculation)

[0137] The preset temperature deviation weighting coefficient is a value pre-set based on the importance of temperature index in coupled simulation during the modeling of the environmental protection cabinet temperature rise; the preset heat flow deviation weighting coefficient is a value pre-set based on the importance of heat flow index in coupled simulation during the modeling of the environmental protection cabinet temperature rise, and the sum of this coefficient and the preset temperature deviation weighting coefficient is 1; the total number of interface nodes is a specific value obtained by counting all interface nodes extracted from the conformal mesh model of heat source load.

[0138] The calculated coupling residual is used to quantify the overall deviation of the solid side and fluid side in terms of temperature and heat flow at the interface node in the current iteration step. By comparing and analyzing the coupling residual with the temperature convergence threshold and heat flow convergence threshold of the environmental protection cabinet, it is possible to determine whether the transient solution process of the fluid-solid-thermal multiphysics coupling simulation model has reached a steady state, and thus obtain the steady-state fluid-thermal coupling simulation results of the environmental protection cabinet.

[0139] First, calculate the difference between the solid-side temperature and the fluid-side temperature at a single interface node. Divide this difference by a normalized temperature reference value and square it. Then multiply the result by a preset temperature deviation weighting coefficient to obtain the temperature deviation contribution value of a single node. Next, calculate the difference between the solid-side heat flux and the fluid-side heat flux at a single interface node. Divide this difference by a normalized heat flux reference value and square it. Then multiply the result by a preset heat flux deviation weighting coefficient to obtain the heat flux deviation contribution value of a single node. Add the temperature deviation contribution value and the heat flux deviation contribution value of a single node to obtain the comprehensive deviation contribution value of a single interface node. Summate the comprehensive deviation contribution values ​​of all interface nodes, divide the sum by the total number of interface nodes, and take the square root to obtain the coupling residual.

[0140] The closer the temperature and heat flow values ​​of the solid and fluid sides at each interface node are, the smaller the temperature deviation contribution and heat flow deviation contribution of a single node, and the smaller the sum of the comprehensive deviation contributions of all nodes, resulting in a smaller final coupling residual value. Conversely, the greater the difference in temperature and heat flow values ​​between the solid and fluid sides at each interface node, the greater the temperature deviation contribution and heat flow deviation contribution of a single node, and the larger the sum of the comprehensive deviation contributions of all nodes, resulting in a larger final coupling residual value. When the coupling residual value gradually decreases and eventually falls below the temperature convergence threshold and heat flow convergence threshold of the environmental protection cabinet, the transient solution process of the fluid-solid-thermal multiphysics coupling simulation model reaches a steady state, the iteration can be stopped, and the steady-state fluid-thermal coupling simulation results of the environmental protection cabinet can be obtained.

[0141] The calculated coupling residual value of the current iteration step is compared and analyzed synchronously with the preset temperature convergence threshold and heat flow convergence threshold of the environmental protection cabinet. If the coupling residual is less than both convergence thresholds at the same time, the model is determined to have reached a steady state. The flow field and temperature field solution data at this time are the steady-state flow-heat coupling simulation results of the environmental protection cabinet. If the convergence requirement is not met, the next round of iterative solution process is continued.

[0142] By setting a fixed time step and using zero as the initial time value for iterative calculation, the ordered transient solution of the fluid-solid-thermal multiphysics coupling simulation model was realized. Through alternating calculation of the solid-fluid region and extraction and exchange of physical quantities at the interface, the calculation process is made to conform to the actual coupling law of the multiphysics field. Then, the steady-state determination is completed by comparing the coupling residual and the double convergence threshold, which ensures the accuracy and reliability of the steady-state fluid-thermal coupling simulation results and provides a calculation data basis that conforms to the actual working state of the environmental protection cabinet for the subsequent correction of the material property library.

[0143] In S5, a high-precision material property library for environmental protection cabinets is obtained, including:

[0144] Simulated temperature data was extracted from the steady-state fluid-thermal coupling simulation results, and measured temperature data at corresponding locations inside the environmental protection cabinet were collected.

[0145] The simulated temperature data and the measured temperature data are compared point by point to obtain the temperature deviation of the environmental protection cabinet. The temperature deviation is then spatially interpolated to obtain the temperature deviation distribution map of the environmental protection cabinet.

[0146] Read the initial thermal conductivity parameters of the solid material region in the conformal mesh model, and identify the area to be corrected in the environmental protection cabinet based on the temperature deviation distribution map;

[0147] Based on the temperature deviation, the initial thermal conductivity parameters of the region to be corrected are iteratively updated to obtain the corrected thermal conductivity parameters of the region to be corrected.

[0148] The corrected thermal conductivity parameters are integrated and packaged to obtain a high-precision material property library for environmental protection cabinets.

[0149] From the steady-state flow-heat coupling simulation results of the environmental protection cabinet, the steady-state temperature value corresponding to each sampling point is extracted according to the preset spatial sampling point position, and the steady-state temperature values ​​of all sampling points are integrated to form the simulation temperature data; at the same time, temperature sensors are deployed in the physical positions inside the environmental protection cabinet that correspond exactly to the sampling points to collect the actual temperature values ​​at each position, and all actual temperature values ​​are organized into measured temperature data.

[0150] The simulated temperature data and the measured temperature data are compared one by one at the same spatial location. The difference between the simulated temperature value and the measured temperature value at each location is calculated. This difference is the temperature deviation at the corresponding location. Using a spatial interpolation method, based on the temperature deviations of each discrete location, the temperature deviation values ​​of all locations within the entire space of the environmental protection cabinet are completed. The temperature deviation values ​​of all locations are then organized according to the spatial coordinate distribution to form a temperature deviation distribution map of the environmental protection cabinet.

[0151] From the material parameter database of the conformal mesh model of the environmental protection cabinet, the initial thermal conductivity parameters corresponding to each mesh unit in the solid material region are retrieved. At the same time, by comparing with the temperature deviation distribution map, the spatial regions where the temperature deviation exceeds the preset allowable range are identified. These regions are the areas of the environmental protection cabinet that need to be corrected for thermal conductivity parameter correction.

[0152] Based on the temperature deviation at each location in the area to be corrected, the initial thermal conductivity parameters of each grid cell in the area to be corrected are adjusted and verified one by one according to the correlation adjustment rules between thermal conductivity parameters and temperature deviation. After each adjustment, the simulated temperature of the area is recalculated and compared with the measured temperature until the temperature deviation drops to the preset allowable range. The thermal conductivity parameters obtained at this time are the corrected thermal conductivity parameters of the area to be corrected.

[0153] The corrected thermal conductivity parameters of the area to be corrected are integrated with the initial thermal conductivity parameters of the uncorrected area. All thermal conductivity parameters are classified and packaged according to material type and spatial region. A precise association between parameters and material identification and spatial location is established, and finally a high-precision material property library of environmental protection cabinets containing the corrected precise parameters is formed.

[0154] By comparing simulated and measured temperatures point by point and using spatial interpolation to form a deviation map, the region to be corrected for thermal conductivity parameters in the conformal mesh model was accurately located. Then, parameter correction was completed through iterative updates based on temperature deviation. Finally, a high-precision material property library was integrated and encapsulated to compensate for the deviation between the initial thermal conductivity parameters and the actual values. This allowed the material property parameters to accurately match the actual heat conduction characteristics of the environmental protection cabinet, providing high-precision parameter support for subsequent temperature rise modeling and prediction, and effectively improving the accuracy of temperature rise modeling results.

[0155] In S6, a simulation model for predicting the temperature rise of the environmental protection cabinet is constructed, including:

[0156] Extract the transient temperature field snapshot sequence from the steady-state flow-heat coupling simulation results under different load conditions, and assemble the transient temperature field snapshot sequence into the temperature field snapshot matrix of the environmental protection cabinet;

[0157] The thermal property parameters of solid material regions in the high-precision material property library are associated and bound with the temperature field snapshot matrix to obtain the temperature field snapshot dataset of the environmental protection cabinet.

[0158] The temperature field snapshot dataset is centered to obtain the temperature field fluctuation dataset of the environmental protection cabinet.

[0159] Eigenvalue decomposition was performed on the temperature field fluctuation dataset to obtain the temperature field fundamental modes of the environmental protection cabinet;

[0160] Obtain the real-time current value sequence and real-time voltage value sequence corresponding to the temperature field snapshot dataset, and normalize the real-time current value sequence and real-time voltage value sequence to obtain the electrical parameter feature vector of the environmental protection cabinet;

[0161] Based on the correspondence between the temperature field fundamental modes and the eigenvectors of electrical parameters, a modal coefficient-electrical parameter mapping matrix is ​​constructed for the environmental protection cabinet;

[0162] By combining and encapsulating the temperature field fundamental modes and the mode coefficient-electrical parameter mapping matrix, a temperature rise prediction simulation model for the environmental protection cabinet is obtained.

[0163] From the steady-state flow-heat coupling simulation results of the environmental protection cabinet, the transient temperature field data corresponding to each time node under different load conditions are selected. The transient temperature field data of each time node is a temperature field snapshot. The temperature field snapshots under all load conditions are arranged in order of load type and time to form a transient temperature field snapshot sequence of the environmental protection cabinet. Then, each temperature field snapshot in the sequence is arranged in the form of matrix elements and assembled into a dimension-matched environmental protection cabinet temperature field snapshot matrix.

[0164] Thermal properties such as thermal conductivity and specific heat capacity are extracted from the high-precision material property library of the environmental protection cabinet. According to the spatial grid cell position of each temperature field snapshot in the temperature field snapshot matrix, the thermal properties are associated with the corresponding elements in the temperature field snapshot matrix one by one. All the corresponding thermal properties are bound to each temperature field snapshot, and the integrated data forms the temperature field snapshot dataset of the environmental protection cabinet.

[0165] The average temperature field of all temperature field snapshots in the temperature field snapshot dataset is calculated. The corresponding value of the average temperature field is subtracted from the temperature value of each temperature field snapshot in the dataset to eliminate the overall offset in the temperature field snapshots. Only the fluctuation part of each temperature field snapshot relative to the average temperature field is retained. The dataset obtained after this centralization process is the temperature field fluctuation dataset of the environmental protection cabinet.

[0166] The intrinsic orthogonal decomposition method is used to decompose the temperature field fluctuation dataset into eigenvalues, solve the covariance matrix of the dataset, calculate the eigenvalues ​​and corresponding eigenvectors of the covariance matrix, sort the eigenvalues ​​in descending order, and select the first few eigenvectors whose contribution rates meet the preset requirements. These eigenvectors are the temperature field fundamental modes that can characterize the main changes in the temperature field of the environmental protection cabinet.

[0167] Retrieve real-time current and voltage data corresponding to each load condition and time point in the temperature field snapshot dataset. Organize these data into real-time current and voltage value sequences in chronological order. Normalize the values ​​in the two sequences by subtracting the minimum value of the sequence from each value and then dividing by the difference between the maximum and minimum values ​​of the sequence, so that all values ​​are mapped to the range of 0 to 1. After processing, the electrical parameter feature vector of the environmental protection cabinet is obtained.

[0168] A mathematical relationship is established between the modal coefficients of the temperature field fundamental modes and the eigenvectors of electrical parameters. By using multiple regression analysis, a quantitative relationship between the modal coefficients and the eigenvectors of electrical parameters is fitted. This quantitative relationship is represented in matrix form, which is the modal coefficient-electrical parameter mapping matrix of the environmental protection cabinet that reflects the correspondence between the two.

[0169] The extracted temperature field fundamental modes are structurally combined with the constructed modal coefficient-electrical parameter mapping matrix, and packaged into a whole according to the data format requirements of the simulation model. The input interface of the model is configured as real-time current value and real-time voltage value, and the output interface is the temperature field prediction result of the environmental protection cabinet. Finally, a temperature rise prediction simulation model for the environmental protection cabinet that can be directly used for temperature rise prediction is formed.

[0170] By extracting core temperature field fundamental modes from temperature field data under multiple operating conditions through intrinsic orthogonal decomposition, redundant temperature field information is removed. At the same time, after normalizing the electrical parameters, a mapping matrix with the mode coefficients is constructed. Finally, the temperature rise prediction simulation model is combined and encapsulated, which greatly simplifies the computational complexity of temperature rise prediction. It can directly and quickly output accurate temperature field prediction results based on real-time current and voltage values, realizing efficient and accurate prediction of temperature rise in environmental protection cabinets, and providing convenient and reliable technical support for temperature rise control of environmental protection cabinets.

[0171] Example 2: As Figure 2 The diagram shows the functional modules of the environmental protection cabinet temperature rise modeling system based on multiphysics coupling, used to implement the method in Example 1, including:

[0172] The conformal mesh model construction module is used to reconstruct the surface of the geometric structure data of the environmental protection cabinet to obtain the three-dimensional geometric surface model of the environmental protection cabinet, and to extract the fluid domain from the three-dimensional geometric surface model to obtain the conformal mesh model of the environmental protection cabinet.

[0173] The heat source density determination module is used to collect the real-time current and voltage values ​​of the heating devices inside the environmental protection cabinet, and combine them with a preset temperature-dependent material property library to determine the time-varying volumetric heat source density distribution of the heating devices.

[0174] The simulation model construction module is used to load the time-varying volumetric heat source density distribution as a volume load onto the solid region of the conformal mesh model, and to set the coupling boundary conditions between the solid region and the fluid region in the conformal mesh model to construct a fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet.

[0175] The simulation model solving module is used to perform transient solutions to the fluid-solid-thermal multiphysics coupling simulation model. During the solution process, the temperature distribution in the solid region and the flow field distribution in the fluid region are updated alternately, and the temperature value and heat flow value are exchanged at the interface to obtain the steady-state fluid-thermal coupling simulation results of the environmental protection cabinet.

[0176] The material property library generation module is used to correct the material thermal conductivity parameters in the conformal mesh model based on the comparison between the steady-state temperature value in the steady-state flow-heat coupling simulation results and the measured temperature value in the environmental protection cabinet, so as to obtain a high-precision material property library for the environmental protection cabinet.

[0177] The temperature rise prediction model construction module is used to perform intrinsic orthogonal decomposition on the high-precision material property library and steady-state flow-heat coupling simulation results to obtain the temperature field fundamental mode of the environmental protection cabinet. Based on the mapping relationship between the temperature field fundamental mode and the real-time current and voltage values, the temperature rise prediction simulation model of the environmental protection cabinet is constructed.

[0178] This system can be installed in electronic devices. Each module can also be called a unit, which refers to a series of computer program segments that can be executed by the processor of an electronic device and can perform a fixed function. They are stored in the memory of the electronic device, and the computer program segments can perform the corresponding functions when executed by the processor.

[0179] The implementation details of each module in this system are the same as in Example 1.

[0180] The system was validated using a full-process algorithm for fluid-solid-thermal multiphysics coupling simulation. For the core technical aspect of temperature rise modeling of the environmental protection cabinet, copper was selected as the test substrate, and simulations were conducted under different current loads, wind speeds, and other conditions. The temperature change trend and coupling residual convergence characteristics were monitored to verify the effectiveness and accuracy of the system in temperature field calculation, coupling residual calculation, boundary condition construction, and transient solution convergence.

[0181] like Figure 3 As shown, operating condition 1 is set with copper material (thermal conductivity 401W / (m・K)), current range 5-20A, ambient temperature 25℃, wind speed 1.0m / s, and temperature convergence threshold 0.001 (dimensionless relative convergence criterion, the subsequent heat flow convergence threshold is the same). Figure 3 The red dashed line represents the measured temperature rise, the blue solid line represents the simulated temperature rise, and the gray dashed line represents the constant ambient temperature. Figure 5 Similarly). Figure 3 The results show that both the measured and simulated temperature rises inside the environmental protection cabinet gradually increase over time and tend to a steady state. The overall trends of the two are highly consistent, with no abnormal fluctuations. This is highly consistent with the actual temperature rise law of the environmental protection cabinet, verifying the accuracy of the temperature field distribution calculation in the transient solution of this system, as well as the matching degree between the time-varying volume heat source density loading and the actual heating conditions.

[0182] like Figure 4 As shown, the heat flow convergence threshold for operating condition 1 is 0.0001. The calculation is carried out based on the coupled residual calculation formula of this system, combined with the dual-dimensional weights of temperature and heat flow. Figure 4 The solid orange line represents the coupling residual, the dashed green line represents the temperature convergence threshold (0.001), and the dashed purple line represents the heat flux convergence threshold (…). Figure 6 Similarly). Figure 4The results show that the coupling residual continuously decreases with iterative solution and eventually converges stably to below the dual thresholds of temperature and heat flow, verifying the reliability of the coupling residual calculation and convergence judgment of this system, as well as the high efficiency of fluid-solid interface data exchange.

[0183] like Figure 5 As shown, operating condition 2 is set with copper material (thermal conductivity 401W / (m・K)), current range 5-25A, ambient temperature 25℃, wind speed 0.8m / s, and temperature convergence threshold 0.001. Figure 5 The results show that as the load changes, both the measured and simulated temperature rises of the environmental protection cabinet gradually increase and reach a steady state. The steady-state temperature value conforms to the physical laws of heat conduction, and the trends of the two are highly consistent, which verifies the accuracy of the temperature field calculation of this system and the degree of restoration of the geometric structure and heat conduction characteristics by the conformal mesh model.

[0184] like Figure 6 As shown, the heat flow convergence threshold for operating condition 2 is 0.0001. Based on the characteristic that the nodes of the conformal mesh interface of this system are completely corresponding, data interaction and coupled residual calculation of the fluid-solid domain are carried out. Figure 6 The coupled residuals show a rapid decrease without rebound, eventually converging below the double threshold, which verifies the accuracy of the coupled boundary condition construction of the system and the efficiency of the transient solution mechanism of alternating updates of the flow field and temperature field, enabling the rapid acquisition of stable fluid-thermal coupling simulation results.

Claims

1. A method for modeling the temperature rise of environmental protection cabinets based on multiphysics coupling, characterized in that, Includes the following steps: S1. Reconstruct the surface of the geometric structure data of the environmental protection cabinet to obtain the three-dimensional geometric surface model of the environmental protection cabinet, and extract the fluid domain from the three-dimensional geometric surface model to obtain the conformal mesh model of the environmental protection cabinet. S2. Collect the real-time current and voltage values ​​of the heating devices inside the environmental protection cabinet, and combine them with the preset temperature-dependent material property library to determine the time-varying volumetric heat source density distribution of the heating devices. S3. The time-varying volumetric heat source density distribution is applied as a volume load to the solid region of the conformal mesh model, and the coupling boundary conditions between the solid region and the fluid region in the conformal mesh model are set to construct a fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet. S4. The fluid-solid-thermal multiphysics coupling simulation model is solved transiently. During the solution process, the temperature distribution in the solid region and the flow field distribution in the fluid region are updated alternately, and the temperature value and heat flow value are exchanged at the interface to obtain the steady-state fluid-thermal coupling simulation results of the environmental protection cabinet. S5. Based on the comparison between the steady-state temperature value and the measured temperature value in the environmental protection cabinet in the steady-state flow-heat coupling simulation results, the material thermal conductivity parameters in the conformal mesh model are corrected to obtain a high-precision material property library for the environmental protection cabinet. S6. Perform intrinsic orthogonal decomposition on the high-precision material property library and steady-state flow-heat coupling simulation results to obtain the temperature field fundamental mode of the environmental protection cabinet. Based on the mapping relationship between the temperature field fundamental mode and the real-time current and voltage values, construct a temperature rise prediction simulation model for the environmental protection cabinet.

2. The method for modeling the temperature rise of an environmental protection cabinet based on multiphysics coupling as described in claim 1, characterized in that, In S1, the process of obtaining the conformal mesh model of the environmental protection cabinet includes: The original point cloud data of the internal cavity and external shell of the environmental protection cabinet are obtained, and the original point cloud data are registered and fused to obtain the closed surface point cloud set of the environmental protection cabinet. The closed surface point cloud is triangularly meshed, and the meshed triangular mesh is smoothed to obtain the initial three-dimensional geometric surface model of the environmental protection cabinet. Identify the closed surface region representing the internal cavity of the environmental protection cabinet in the initial three-dimensional geometric surface model, and mark the fluid domain boundary in the initial three-dimensional geometric surface model according to the relative positional relationship between the closed surface region and the outer shell surface in the environmental protection cabinet. Based on the fluid domain boundary, the fluid domain surface model of the environmental protection cabinet is extracted from the initial three-dimensional geometric surface model; By integrating the fluid domain surface model and the solid domain surface model of the environmental protection cabinet, a composite geometric model of the environmental protection cabinet is obtained. The fluid domain part of the composite geometric model is discretized into an unstructured hexahedral mesh, the solid domain part of the composite geometric model is discretized into a tetrahedral mesh, and a conformal mesh interface with completely corresponding nodes is generated at the interface between the fluid domain and the solid domain to obtain the conformal mesh model of the environmental protection cabinet.

3. The method for modeling the temperature rise of an environmental protection cabinet based on multiphysics coupling as described in claim 1, characterized in that, In S2, the process of determining the time-varying volumetric heat source density distribution of the heating device includes: Obtain the original current sampling sequence and original voltage sampling sequence of the heating device inside the environmental protection cabinet during the monitoring period; The original current sampling sequence and the original voltage sampling sequence are timestamped to obtain the synchronous current timing data and synchronous voltage timing data of the environmental protection cabinet; Based on the material identifier of the heating device, the corresponding resistivity-temperature relationship data is extracted from a preset temperature-dependent material property library; The estimated temperature field distribution data of the environmental protection cabinet at the initial moment is obtained, and the temperature value of the spatial location of the heating device is extracted from the estimated temperature field distribution data as the current temperature input of the environmental protection cabinet. Linear interpolation is performed on the current temperature input and resistivity-temperature relationship data to obtain the current resistivity of the heating device, and the equivalent resistance of the heating device is determined by combining the geometric parameters of the heating device. Based on the synchronous current timing data and equivalent resistance, the instantaneous heating power timing data of the heating device is determined, and based on the geometric volume of the heating device, the instantaneous heating power timing data is converted into the time-varying volumetric heat source density distribution of the heating device.

4. The method for modeling the temperature rise of an environmental protection cabinet based on multiphysics coupling as described in claim 1, characterized in that, In S3, the time-varying volumetric heat source density distribution is applied as a volume load to the solid region of the conformal mesh model, specifically including: Read the grid cell identifier information and corresponding geometric center coordinates belonging to the solid region in the conformal mesh model to obtain the solid cell index table of the environmental protection cabinet; Traverse the grid cells in the solid element index table, determine the corresponding heating device based on the geometric center coordinates, and assign the time-varying volume heat source density distribution of the heating device to the grid cell to obtain the solid element-heat source density mapping relationship of the environmental protection cabinet. Based on the solid element-heat source density mapping relationship, the heat source density of the solid region is written into the data structure of the conformal mesh model in the form of a scalar field, thus obtaining the conformal mesh model of the heat source load of the environmental protection cabinet.

5. The method for modeling the temperature rise of an environmental protection cabinet based on multiphysics coupling as described in claim 4, characterized in that, In S3, coupling boundary conditions are set between the solid region and the fluid region in the conformal mesh model to construct a fluid-solid-thermal multiphysics coupling simulation model for the environmental protection cabinet. Specifically, this includes: The grid nodes at the interface between the solid and fluid regions are extracted from the conformal grid model of the heat source load to obtain the boundary nodes of the environmental protection cabinet, and a topological association record between the adjacent regions on the solid side and the adjacent regions on the fluid side is established for the boundary nodes. Based on the topology association record, a data exchange channel is defined on the boundary node, and the configuration information of the data exchange channel is bound to the identifier of the boundary node to obtain the coupling boundary conditions of the environmental protection cabinet. By integrating the coupled boundary conditions and the conformal mesh model of the heat source load, a fluid-solid-thermal multiphysics coupled simulation model of the environmental protection cabinet is obtained.

6. The method for modeling the temperature rise of an environmental protection cabinet based on multiphysics coupling as described in claim 1, characterized in that, In S4, the process of obtaining the steady-state flow-heat coupling simulation results of the environmental protection cabinet includes: Set the current time step and initialize the current time to zero. Within the current time step, execute the following iterative process; Based on the solid region temperature distribution of the previous iteration step, the flow field of the fluid region is calculated to obtain the fluid region flow field distribution of the current iteration step, and the fluid side temperature value and fluid side heat flux value at the interface node are extracted from the fluid region flow field distribution. Using the fluid-side temperature and fluid-side heat flow as boundary conditions, the temperature field of the solid region is solved to obtain the solid region temperature distribution in the current iteration step, and the solid-side temperature and solid-side heat flow values ​​at the interface nodes are extracted from the solid region temperature distribution. Calculate the coupling residual of the current iteration step based on the solid-side temperature value, fluid-side temperature value, solid-side heat flow value, and fluid-side heat flow value; The coupling residuals are compared and analyzed with the temperature convergence threshold and heat flow convergence threshold of the environmental protection cabinet to obtain the steady-state flow-heat coupling simulation results of the environmental protection cabinet.

7. The method for modeling the temperature rise of an environmental protection cabinet based on multiphysics coupling as described in claim 6, characterized in that, The formula for calculating the coupling residual is: ； in, Indicates coupling residuals, This represents the solid-side temperature value at the i-th interface node in the current iteration step, where N is the number of interface nodes. This represents the fluid-side temperature value at the i-th interface node in the current iteration step. This represents the solid-side heat flux value at the i-th interface node in the current iteration step. This represents the fluid-side heat flux value at the i-th interface node in the current iteration step. This indicates the normalized reference value for the temperature of the eco-friendly cabinet. This indicates the normalized reference value of the heat flow of the environmental protection cabinet. This represents the preset temperature deviation weighting coefficient. This represents the preset heat flow deviation weighting coefficient, and .

8. The method for modeling the temperature rise of an environmental protection cabinet based on multiphysics coupling as described in claim 1, characterized in that, In S5, the process of obtaining a high-precision material property library for environmental protection cabinets includes: Simulated temperature data was extracted from the steady-state fluid-thermal coupling simulation results, and measured temperature data at corresponding locations inside the environmental protection cabinet were collected. The simulated temperature data and the measured temperature data are compared point by point to obtain the temperature deviation of the environmental protection cabinet. The temperature deviation is then spatially interpolated to obtain the temperature deviation distribution map of the environmental protection cabinet. Read the initial thermal conductivity parameters of the solid material region in the conformal mesh model, and identify the area to be corrected in the environmental protection cabinet based on the temperature deviation distribution map; Based on the temperature deviation, the initial thermal conductivity parameters of the region to be corrected are iteratively updated to obtain the corrected thermal conductivity parameters of the region to be corrected. The corrected thermal conductivity parameters are integrated and packaged to obtain a high-precision material property library for environmental protection cabinets.

9. The method for modeling the temperature rise of an environmental protection cabinet based on multiphysics coupling as described in claim 1, characterized in that, In S6, the process of constructing a temperature rise prediction simulation model for the environmental protection cabinet includes: Extract the transient temperature field snapshot sequence from the steady-state flow-heat coupling simulation results under different load conditions, and assemble the transient temperature field snapshot sequence into the temperature field snapshot matrix of the environmental protection cabinet; The thermal property parameters of solid material regions in the high-precision material property library are associated and bound with the temperature field snapshot matrix to obtain the temperature field snapshot dataset of the environmental protection cabinet. The temperature field snapshot dataset is centered to obtain the temperature field fluctuation dataset of the environmental protection cabinet. Eigenvalue decomposition was performed on the temperature field fluctuation dataset to obtain the temperature field fundamental modes of the environmental protection cabinet; Obtain the real-time current value sequence and real-time voltage value sequence corresponding to the temperature field snapshot dataset, and normalize the real-time current value sequence and real-time voltage value sequence to obtain the electrical parameter feature vector of the environmental protection cabinet; Based on the correspondence between the temperature field fundamental modes and the eigenvectors of electrical parameters, a modal coefficient-electrical parameter mapping matrix is ​​constructed for the environmental protection cabinet; By combining and encapsulating the temperature field fundamental modes and the mode coefficient-electrical parameter mapping matrix, a temperature rise prediction simulation model for the environmental protection cabinet is obtained.

10. A system for modeling the temperature rise of an environmentally friendly cabinet based on multi-physics coupling, used to implement the method for modeling the temperature rise of an environmentally friendly cabinet based on multi-physics coupling as described in any one of claims 1-9, characterized in that, include: The conformal mesh model construction module is used to reconstruct the surface of the geometric structure data of the environmental protection cabinet to obtain the three-dimensional geometric surface model of the environmental protection cabinet, and to extract the fluid domain from the three-dimensional geometric surface model to obtain the conformal mesh model of the environmental protection cabinet. The heat source density determination module is used to collect the real-time current and voltage values ​​of the heating devices inside the environmental protection cabinet, and combine them with a preset temperature-dependent material property library to determine the time-varying volumetric heat source density distribution of the heating devices. The simulation model construction module is used to load the time-varying volumetric heat source density distribution as a volume load onto the solid region of the conformal mesh model, and to set the coupling boundary conditions between the solid region and the fluid region in the conformal mesh model to construct a fluid-solid-thermal multiphysics coupling simulation model of the environmental protection cabinet. The simulation model solving module is used to perform transient solutions to the fluid-solid-thermal multiphysics coupling simulation model. During the solution process, the temperature distribution in the solid region and the flow field distribution in the fluid region are updated alternately, and the temperature value and heat flow value are exchanged at the interface to obtain the steady-state fluid-thermal coupling simulation results of the environmental protection cabinet. The material property library generation module is used to correct the material thermal conductivity parameters in the conformal mesh model based on the comparison between the steady-state temperature value in the steady-state flow-heat coupling simulation results and the measured temperature value in the environmental protection cabinet, so as to obtain a high-precision material property library for the environmental protection cabinet. The temperature rise prediction model construction module is used to perform intrinsic orthogonal decomposition on the high-precision material property library and steady-state flow-heat coupling simulation results to obtain the temperature field fundamental mode of the environmental protection cabinet. Based on the mapping relationship between the temperature field fundamental mode and the real-time current and voltage values, the temperature rise prediction simulation model of the environmental protection cabinet is constructed.

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