Multi-layer multi-pass welding full-process simulation system based on Abaqus kernel

Abstract

The invention discloses a multi-layer multi-pass welding full-process simulation system based on an Abaqus kernel, and relates to the technical field of multi-layer multi-pass welding, the system deeply calls an Abaqus kernel API through a Python script to generate an integrated operation interface with a tree-shaped navigation bar, a welding simulation full-process code driving framework is constructed by packaging a plurality of Python function modules of the Abaqus kernel API, and a multi-layer multi-pass welding full-process code driving framework is constructed by packaging a plurality of Python function modules of the Abaqus kernel API. Parameterized structure modeling, transition grid division, sequential laying of multiple welding seams, dynamic configuration of heat source subprograms and thermal-force collaborative analysis full-process simulation of multi-pass welding can be achieved, multi-type multi-layer multi-pass welding simulation results are obtained and used for evaluating the welding quality and effect, and support is provided for quality evaluation and parameter optimization of multi-layer multi-pass welding.

Description

Technical Field

[0001] This application relates to the field of multilayer and multipass welding technology, and in particular to a multilayer and multipass welding full-process simulation system based on the Abaqus kernel. Background Technology

[0002] Multi-pass welding is an indispensable joining technology in key industrial fields such as heavy equipment manufacturing, shipbuilding, oil and gas pipelines, and pressure vessels. This technology involves depositing filler metal layer by layer in multiple passes to ultimately form a welded joint that meets requirements. This process can weld thick and large components, and through the "tempering" effect of subsequent weld passes on previous passes, it refines the grains and improves the microstructure, thereby enhancing the overall mechanical properties of the joint. However, multi-pass welding is a highly complex physicochemical process, involving strong spatiotemporal coupling effects of multiple physical fields, including arc physics, molten pool dynamics, heat and mass transfer, phase transformation metallurgy, and stress-strain evolution caused by rapid and uneven heating and cooling. This complexity leads to process design and quality control heavily relying on engineers' experience and extensive process testing, making it difficult to guarantee weld quality. Summary of the Invention

[0003] To address the aforementioned problems and technical requirements, this application proposes a multi-layer, multi-pass welding full-process simulation system based on the Abaqus kernel. The technical solution of this application is as follows: A multi-layer, multi-pass welding full-process simulation system based on the Abaqus kernel, comprising: The main program calls a module used to start the Abaqus computing environment and call Python scripts; The kernel interaction layer, built on the abaqusGuiToolset library, is used to realize real-time bidirectional communication between the integrated operation interface and the Abaqus kernel. The integrated user interface includes a tree-structured navigation toolkit for the structured display and management of multiple Python functional modules that encapsulate the Abaqus core API. These Python functional modules include: The structural modeling module is used to construct the geometric model of the base material; The weld modeling module is used to generate multi-layer, multi-pass weld geometry on the base material geometry model based on the input weld parameters, and obtain a simulation model. The transition mesh generation module is used to mesh the base material geometry model and the weld geometry according to the preset mesh size and transition ratio. The life and death unit module is used to divide the life and death unit set according to the welding layer sequence and perform correlation analysis steps to realize weld activation. The welding heat source generation module is used to acquire welding heat source parameters and generate welding heat sources that act on the simulation model according to the welding heat source parameters. The thermal analysis module is used to obtain the thermophysical property parameters of the base material as temperature changes and allocate them to the entire simulation model. Based on the thermophysical property parameters and the welding heat source, thermal analysis is performed to obtain temperature field data and then transmitted to the stress field analysis module. The stress field analysis module is used to perform force analysis based on the temperature field data transmitted from the thermal analysis module and obtain simulation results of multi-layer multi-pass welding.

[0004] The further technical solution is that the stress field analysis module includes a fixture constraint setting module, a stress field analysis setting module, and a post-processing module: The tooling and fixture constraint setting module is used to pick up fixed endpoints and set constraints based on the fixed endpoints; The stress field analysis setting module is used to obtain welding-cooling analysis steps, interactions, and load parameters, and to create static mechanical welding, cooling analysis steps, interactions, and loads that match the thermal analysis in batches. Under constraints, it realizes the collaborative calculation of temperature field and stress field to obtain stress field data. The post-processing module is used to obtain multi-layer, multi-pass welding simulation results based on temperature field data and stress field data.

[0005] The further technical solution is that the post-processing module obtains multi-layer multi-pass welding simulation results based on temperature field data and stress field data, including temperature distribution data, stress distribution data, strain distribution data along any path, welding transient thermal cycle curve, three-dimensional cloud map of residual stress field, and structural deformation vector map.

[0006] A further technical solution is that the transition ratio used in the transition mesh division module is 3:1 or 4:2.

[0007] The further technical solution is a transition mesh division module, which is used to obtain the three-dimensional coordinates of the midpoint, bottom and origin of the transition zone of the base material geometric model on each side of the weld geometry. Based on the three-dimensional coordinates of the midpoint, bottom and origin of the transition zone, the base material geometric model on the current side of the weld geometry is meshed according to the transition ratio. After completing the mesh transition division of the base material geometric models on both sides of the weld geometry, the transition zone is divided out for seeding and sweeping settings, and the weld area, near weld area and base material area are divided in sequence according to the weld sequence.

[0008] The further technical solution is a birth and death unit module, which is used to obtain the starting unit number and the incremental step number, discretize the weld area into multiple unit sets according to the welding layer sequence based on the starting unit number and the incremental step number, and modify the birth and death state of the corresponding unit set in the corresponding analysis step to realize the activation of each weld and simulate the metal deposition process.

[0009] A further technical solution involves the welding heat source generation module acquiring welding heat source parameters including start time and thermal power. Double ellipsoidal heat source shape parameters , , , Heat input distribution coefficient of the front half-ellipsoid Heat input distribution coefficient of the rear hemispherical ellipsoid The welding heat source generation module generates a welding heat source that acts on the simulation model from the start time according to the welding heat source parameters, and: Position on the front half of the ellipsoid in the simulation model Energy density at ; Position on the rear hemisphere in the simulation model Energy density at ; Among them, thermal power It is the product of welding voltage, welding current, and welding thermal efficiency.

[0010] The further technical solution is that the thermophysical property parameters of the base material obtained by the thermal analysis module as a function of temperature include: the elastic modulus, Poisson's ratio, density, specific heat, thermal conductivity, coefficient of thermal expansion, and yield strength of the base material at various different temperatures.

[0011] A further technical solution is a structural modeling module, used to obtain the structural type and geometric parameters, and to set the standard joint model of the corresponding structural type according to the geometric parameters to obtain the base material geometric model. The geometric parameters include bevel angle, plate size, and gap size; or, a structural modeling module, used to obtain the directly imported base material geometric model.

[0012] The further technical solution is that the weld parameters obtained by the weld modeling module include the weld boundary, the weld stretching direction and the weld leg length. The weld modeling module is used to generate weld geometry within the weld boundary, along the weld stretching direction and according to the weld leg length.

[0013] The beneficial technical effects of this application are: This application discloses a multi-layer, multi-pass welding full-process simulation system based on the Abaqus kernel. The system uses Python scripts to deeply call the Abaqus kernel API (such as mdb and session objects) to generate a brand-new GUI interface with a tree-shaped navigation bar. By encapsulating multiple Python functional modules of the Abaqus kernel API, it constructs a code-driven architecture for the entire welding simulation process, providing an intuitive graphical interface. It can easily realize parametric structural modeling, transition mesh generation, sequential laying of multi-pass welds, dynamic configuration of heat source subroutines, and thermo-mechanical co-analysis for multi-pass welding. It can realize the full-process simulation of multi-layer, multi-pass welding and obtain various types of multi-layer, multi-pass welding simulation results for evaluating welding quality and effect, providing support for the quality assessment and parameter optimization of multi-layer, multi-pass welding.

[0014] This system, through modular design, parametric configuration, and automated script integration, creates a brand-new GUI interface with a tree-shaped navigation bar for "welding simulation." It can automate the entire process from modeling, analysis, to post-processing, eliminating dependence on external tools and enabling "one-click" simulation, improving efficiency by more than 50%. Furthermore, its open Python architecture supports user-defined development modules, which can be expanded to include welding process types, material models, post-processing algorithms, and other functions. New modules can be seamlessly integrated into existing systems.

[0015] This system supports linked adjustment of core parameters, eliminates the need for model reconstruction during operating condition switching, and adapts to the needs of multi-joint, multi-weld, and multi-process scenarios. Based on the native Abaqus kernel driver, it supports 3:1 / 4:2 non-uniform transition strategies, parameterizes and visualizes mesh density gradients with one click, and allows for variable mesh size to avoid analysis errors caused by abrupt mesh changes, balancing accuracy and efficiency. It achieves automatic transfer of temperature and stress fields through batch creation of predefined fields, combining the high precision of sequential coupling with the advantages of process automation, and is suitable for complex multi-layer, multi-pass welding process simulation modeling. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the multi-layer, multi-pass welding full-process simulation system implemented through multiple Python functional modules.

[0017] Figure 2 This is a schematic diagram of a base material geometric model constructed based on structural type and geometric parameters in an example.

[0018] Figure 3 yes Figure 2 A schematic diagram of the weld geometry generated based on weld parameters in the example.

[0019] Figure 4 yes Figure 3 The example illustrates the transition mesh division using two different transition ratios. Figure 5 yes Figure 4 A schematic diagram of the temperature distribution data obtained from the example.

[0020] Figure 6 yes Figure 4 A schematic diagram of the stress distribution data obtained from the example. Detailed Implementation

[0021] The specific embodiments of this application will be further described below with reference to the accompanying drawings.

[0022] This application discloses a multi-layer, multi-pass welding full-process simulation system based on the Abaqus kernel. The multi-layer, multi-pass welding full-process simulation system includes: The main program calls a module used to start the Abaqus computing environment and call Python scripts.

[0023] The kernel interaction layer, built on the abaqusGuiToolset library, is used to achieve real-time bidirectional communication between the integrated user interface and the AbaqusCAE kernel, ensuring efficient collaboration between Python scripts and the Abaqus CAE kernel. In one embodiment, the specific connection method between Python and the Abaqus kernel is based on the Python API interface of Abaqus CAE. The kernel module is loaded through the "import abaqus" statement, establishing inter-process communication between the Python interpreter and the Abaqus kernel.

[0024] The integrated user interface includes a tree-structured navigation toolkit for the structured display and management of multiple Python functional modules that encapsulate the Abaqus kernel API. In one embodiment, a new main window GUI interface with a "Welding Simulation" tree-structured navigation bar is created, containing a four-level menu: "Parametric Modeling - Thermal Analysis - Force Analysis - Post-processing." Each menu item is bound to a corresponding Python functional module, enabling code-level communication between the GUI and the kernel. The framework consists of an executable program (Run.bat), a startup program (myApp.py), a main window program (caeMainWindow.py), a tree-structured toolkit program (CompositeTreeToolsetGui.py), and multiple Python functional modules. All files are developed in Python, supporting one-click startup and module sharing.

[0025] The system includes several Python functional modules, as shown below. Please refer to them. Figure 1 : (1) Structural modeling module, used to construct the geometric model of the parent material.

[0026] This structural modeling module is used to acquire structural types and geometric parameters, and to obtain the base material geometric model by setting the standard joint model corresponding to the structural type based on the geometric parameters. Structural types include flat plates and T-joints, and geometric parameters include bevel angles, plate dimensions, and gap dimensions. This module uses a dynamic mapping mechanism between structural types and parameters to flexibly switch between flat plates, T-joints, and other structures. It provides schematic diagrams to assist parameter input and uses a trigonometric function analytical algorithm to accurately generate bevel contours that conform to welding standards. The bevel contours are reconstructed in real time, sketches are drawn, and extruded into solids, achieving accurate modeling of the base material and bevel of the welded structure. By picking the boundary to be welded and the extrusion path, it can arbitrarily generate 3D solids for root pass, fill pass, and cap pass welds that are topologically related to the base material, reducing manual weld bead cutting. Therefore, it eliminates the need for external software modeling and avoids data conversion losses.

[0027] In addition, this module also supports one-click import of existing models. By inputting the path or selecting the file, the .cae model can be loaded, and the structural modeling module can directly obtain the imported parent material geometric model.

[0028] For example, in one instance, the structural modeling module obtains a flat plate structure with geometric parameters including a plate thickness of 4mm, a plate length of 60mm, a plate width of 20mm, and a V-groove with a 60° bevel angle. The structural modeling module can then automatically construct the base material geometric model based on the standard joint model of the flat plate and these geometric parameters. Figure 2 As shown.

[0029] (2) The weld modeling module is used to generate multi-layer, multi-pass weld geometry on the base metal geometry model based on the input weld parameters, thus obtaining the simulation model. The weld parameters obtained by the weld modeling module include the weld boundary, weld stretching direction, and weld leg length. The weld modeling module is used to generate weld geometry within the weld boundary, along the weld stretching direction and according to the weld leg length, thereby achieving automatic association of the topological relationship between the weld and the base metal without entering the sketch module.

[0030] For example, in one instance, taking multi-layer, multi-pass welding using manual TIG welding, including a first root pass and a second fill pass, based on... Figure 2 The base metal geometry model and the weld parameters obtained by the weld modeling module include: using the two sides of the bevel of the base metal geometry model as weld boundaries SideEdge1 and SideEdge2, the weld stretching direction AlongPath is along the bevel extension direction, and the weld leg length LegLength1 = 2.309 mm. The weld modeling module can then automatically generate a 2-layer, 2-pass weld geometry, such as... Figure 3 As shown, BottomEdge represents the top edge of the root weld.

[0031] (3) Transition mesh generation module, used to mesh the base material geometry model and weld geometry according to the preset mesh size and transition ratio.

[0032] Based on the native Abaqus kernel driver, the transition meshing module supports 3:1 and 4:2 non-uniform transition strategies. This module obtains the 3D coordinates of the midpoint, bottom, and origin of the transition zone of the base material geometry model on each side of the weld geometry. Based on these coordinates, it performs mesh transitioning on the base material geometry model on the current side of the weld geometry according to the transition ratio. Specifically, it calls the corresponding generation module based on the selected ratio, first constructing a baseline sketch of the transition zone, adapting it to the structural dimensions using a scaling algorithm, and then expanding it into a gradient template using a linear array. Based on the input 3D coordinates of the midpoint, bottom, and origin of the transition zone, it achieves precise alignment between the sketch and the structure. After completing the mesh transitioning of the base material geometry models on both sides of the weld geometry, the transition zone is segmented for seeding and sweep settings. The weld region, near-weld region, and base material region are divided sequentially according to the weld bead sequence to ensure compatibility with the birth and death element generation logic. The thermal analysis element type is DC3D8. Region segmentation divides the transition zone into a high-quality gradient transition mesh, avoiding element distortion and abrupt size changes. The entire process is based on the native Abaqus kernel driver, without relying on external meshing tools, and the mesh and geometry have good compatibility.

[0033] For example in Figure 2 and Figure 3 In this example, the transition mesh generation module obtains the midpoint coordinates (MidpointCoordinate_XYZ = -8.8094, 4, 30), boundary coordinates (BottomCoordinate_XYZ = -8.8094, 4, 60), and originalCoordinate_XYZ = -6.3094, 4, 0) of the base metal geometry model on one side of the weld geometry. By setting the mesh size to 1mm for the weld region and 3mm for the base metal region, a mesh transition segmentation is generated on one side using a 3:1 transition ratio. This automatically generates the mesh transition segmentation on one side of the weld geometry, as shown below. Figure 4 As shown, the same operation is performed on the other side. Mesh transition segmentation can also be performed when using a 4:1 transition ratio.

[0034] (4) The birth and death unit module is used to divide the birth and death unit sets according to the welding layer sequence and associate the analysis steps to realize weld activation. Specifically, the birth and death unit module obtains the starting unit number and the incremental step number, discretizes the weld area into multiple unit sets according to the starting unit number and the incremental step number according to the welding layer sequence, and modifies the birth and death state of the corresponding unit set in the corresponding analysis step to realize the activation of each weld and simulate the metal deposition process. Based on the loop interception algorithm and parameter standardization transfer, the birth and death unit sets matching multiple welds are generated in batches. Through the model state change logic, the dynamic timing matching of "number of unit sets - number of welds - activation sequence" is realized to ensure that the activation order of the unit sets is consistent with the welding sequence, realize the code-level collaboration between thermal boundary and unit activation, and realistically simulate the process of adding weld metal one by one.

[0035] (5) A welding heat source generation module, used to acquire welding heat source parameters and generate a welding heat source acting on the simulation model according to the welding heat source parameters. In one embodiment, the welding heat source parameters acquired by the welding heat source generation module include start time and thermal power. Double ellipsoidal heat source shape parameters , , , Heat input distribution coefficient of the front half-ellipsoid Heat input distribution coefficient of the rear hemispherical ellipsoid Among them, thermal power It is the product of welding voltage, welding current, and welding thermal efficiency.

[0036] The welding heat source generation module generates welding heat sources that act on the simulation model from the start time according to the welding heat source parameters, and: the position located on the front half of the ellipsoid in the simulation model is... Energy density at The position on the rear hemisphere in the simulation model. Energy density at .

[0037] The welding heat source generation module is based on the "parameter input - path processing - heat source adaptation - subroutine generation" model. Through standardized parameter table definition, adaptive path discretization and splicing, dynamic extraction of normal vectors, and collaborative parameter calculation, it achieves accurate matching of heat source parameters with welding path and process parameters. It calculates heat source movement parameters through path discretization algorithm, generates and loads heat source subroutines in .for format, verifies path validity using regular expressions, and automatically generates heat source subroutines and thermal analysis jobs adapted to Abaqus, ensuring the timing and spatial distribution accuracy of heat source loading.

[0038] (6) Thermal analysis module, used to obtain the thermophysical performance parameters of the base material as the temperature changes and allocate them to the entire simulation model. Based on the thermophysical performance parameters and the welding heat source, thermal analysis is performed to obtain temperature field data and transmit it to the stress field analysis module.

[0039] The thermal analysis module acquires the following thermophysical property parameters of the base material as a function of temperature: elastic modulus, Poisson's ratio, density, specific heat, thermal conductivity, coefficient of thermal expansion, and yield strength at various temperatures. The module supports parameterized configuration of the welding step (Wstep) and cooling step (Cstep), including parameters such as time period, maximum number of increments, initial increment, and maximum allowable temperature increment. Based on these parameters, it automatically creates transient welding and cooling analysis steps, interactions, loads, and predefined fields in batches. Convection boundary conditions are set by writing the *FILM keyword.

[0040] The stress field analysis module seamlessly transfers temperature field data from the predefined field loading thermal analysis module in FROM_FILE format to the stress field, avoiding the result deviations caused by manual temperature field transfer and time asynchrony. Force analysis is then performed to obtain multi-layer, multi-pass welding simulation results. Specifically, the stress field analysis module includes a fixture constraint setting module, a stress field analysis setting module, and a post-processing module. (7) Fixture constraint setting module, used to pick up fixed endpoints and set constraints based on fixed endpoints. Remember that constraints are set through the Fix module in three types: Fix_xyz, Fix_yz, and Fix_z. Fix_xyz is a full constraint that restricts displacement in three directions: U1, U2, and U3. Fix_yz restricts displacement in the directions of U2 and U3. Fix_z is a unidirectional constraint that only restricts displacement in the direction of U3.

[0041] (8) Stress field analysis setting module, used to acquire welding-cooling analysis steps, interaction, and load parameters, and sequentially couple them in a fully automated manner to create static mechanical welding, cooling analysis steps, interaction, and loads that match the thermal analysis in batches. Under constraints, it realizes the collaborative calculation of temperature field and stress field to obtain stress field data. It integrates input boxes for model name, boundary condition name, and analysis step name, as well as viewport picking function, and automatically binds user parameters and Abaqus kernel call commands to complete assembly constraint configuration.

[0042] (9) Post-processing module, used to obtain multi-layer multi-pass welding simulation results based on temperature field data and stress field data. The post-processing module supports selecting ODB files, extraction paths, analysis steps, and frame numbers. The extracted multi-layer multi-pass welding simulation results include temperature distribution data, stress distribution data, strain distribution data along any path, welding transient thermal cycle curves, three-dimensional cloud maps of residual stress fields, and structural deformation vector maps. The obtained multi-layer multi-pass welding simulation results can be automatically generated into a CSV format data file and output to a specified directory. For example, in... Figures 2-4 In the example, the final extracted temperature distribution data is as follows: Figure 5 As shown, the stress distribution data is as follows: Figure 6 As shown.

[0043] The above descriptions are merely preferred embodiments of this application, and this application is not limited to the above embodiments. It is understood that other improvements and variations that can be directly derived or conceived by those skilled in the art without departing from the spirit and concept of this application should be considered to be included within the protection scope of this application.

Claims

1. A simulation system for the entire multi-layer, multi-pass welding process based on the Abaqus kernel, characterized in that, The multi-layer, multi-pass welding full-process simulation system includes: The main program calls a module used to start the Abaqus computing environment and call Python scripts; The kernel interaction layer, built on the abaqusGuiToolset library, is used to realize real-time bidirectional communication between the integrated operation interface and the Abaqus kernel. The integrated user interface includes a tree-structured navigation toolkit for the structured display and management of multiple Python functional modules that encapsulate the Abaqus core API. These Python functional modules include: The structural modeling module is used to construct the geometric model of the base material; The weld modeling module is used to generate multi-layer, multi-pass weld geometry on the base material geometry model based on the input weld parameters, and obtain a simulation model. The transition mesh generation module is used to mesh the base material geometry model and the weld geometry according to the preset mesh size and transition ratio. The life and death unit module is used to divide the life and death unit set according to the welding layer sequence and perform correlation analysis steps to realize weld activation. The welding heat source generation module is used to acquire welding heat source parameters and generate welding heat sources that act on the simulation model according to the welding heat source parameters. The thermal analysis module is used to obtain the thermophysical property parameters of the base material as a function of temperature and distribute them to the entire simulation model. Based on the thermophysical property parameters and the welding heat source, thermal analysis is performed to obtain temperature field data and then transmitted to the stress field analysis module. The stress field analysis module is used to perform force analysis based on the temperature field data transmitted from the thermal analysis module and obtain simulation results of multi-layer multi-pass welding.

2. The multi-layer, multi-pass welding full-process simulation system according to claim 1, characterized in that, The stress field analysis module includes a fixture constraint setting module, a stress field analysis setting module, and a post-processing module. The tooling and fixture constraint setting module is used to pick up fixed endpoints and set constraints based on the fixed endpoints; The stress field analysis setting module is used to obtain welding-cooling analysis steps, interactions, and load parameters, and to create static mechanical welding, cooling analysis steps, interactions, and loads that match the thermal analysis in batches. Under constraints, it realizes the collaborative calculation of temperature field and stress field to obtain stress field data. The post-processing module is used to obtain multi-layer, multi-pass welding simulation results based on temperature field data and stress field data.

3. The multi-layer, multi-pass welding full-process simulation system according to claim 2, characterized in that, The post-processing module obtains multi-layer, multi-pass welding simulation results based on temperature field data and stress field data, including temperature distribution data, stress distribution data, strain distribution data along any path, welding transient thermal cycle curve, three-dimensional cloud map of residual stress field, and structural deformation vector map.

4. The multi-layer, multi-pass welding full-process simulation system according to claim 1, characterized in that, The transition ratio used in the transition mesh generation module is 3:1 or 4:

2.

5. The multi-layer, multi-pass welding full-process simulation system according to claim 4, characterized in that, The transition mesh generation module is used to obtain the three-dimensional coordinates of the midpoint, bottom, and origin of the transition zone of the base material geometry model on each side of the weld geometry. Based on the three-dimensional coordinates of the midpoint, bottom, and origin of the transition zone, the base material geometry model on the current side of the weld geometry is meshed according to the transition ratio. After completing the mesh transition of the base material geometry models on both sides of the weld geometry, the transition zone is separated for seeding and sweep settings. The weld area, near-weld area, and base material area are divided in sequence according to the weld sequence.

6. The multi-layer, multi-pass welding full-process simulation system according to claim 1, characterized in that, The life and death unit module is used to obtain the starting unit number and the increment step number. According to the welding layer sequence, the weld area is discretized into multiple unit sets based on the starting unit number and the increment step number. The life and death status of the corresponding unit set is modified in the corresponding analysis step to realize the activation of each weld layer and simulate the metal deposition process.

7. The multi-layer, multi-pass welding full-process simulation system according to claim 1, characterized in that, The welding heat source parameters acquired by the welding heat source generation module include start time and thermal power. Double ellipsoidal heat source shape parameters , , , Heat input distribution coefficient of the front half-ellipsoid Heat input distribution coefficient of the rear hemispherical ellipsoid ; The welding heat source generation module generates welding heat sources that act on the simulation model from the start time according to the welding heat source parameters, and: Position on the front half of the ellipsoid in the simulation model Energy density at ; Position on the rear hemisphere in the simulation model Energy density at ; Among them, thermal power It is the product of welding voltage, welding current, and welding thermal efficiency.

8. The multi-layer, multi-pass welding full-process simulation system according to claim 1, characterized in that, The thermophysical property parameters of the base material obtained by the thermal analysis module as a function of temperature include: elastic modulus, Poisson's ratio, density, specific heat, thermal conductivity, coefficient of thermal expansion, and yield strength of the base material at various temperatures.

9. The multi-layer, multi-pass welding full-process simulation system according to claim 1, characterized in that, The structural modeling module is used to obtain the structural type and geometric parameters, and to set the standard joint model of the corresponding structural type according to the geometric parameters to obtain the base material geometric model. The geometric parameters include bevel angle, plate size, and gap size; or, the structural modeling module is used to obtain the directly imported base material geometric model.

10. The multi-layer, multi-pass welding full-process simulation system according to claim 1, characterized in that, The weld parameters obtained by the weld modeling module include the weld boundary, weld stretching direction, and weld leg length. The weld modeling module is used to generate weld geometry within the weld boundary, along the weld stretching direction, according to the weld leg length.

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