Stress distribution evaluation method and device of superconducting magnet, electronic equipment and storage medium

Abstract

The invention discloses a stress distribution evaluation method and device of a superconducting magnet, electronic equipment and a storage medium, and belongs to the field of stress distribution calculation.The method comprises the steps that a finite element model of the superconducting magnet is obtained, winding simulation and cooling simulation are sequentially carried out, winding stress distribution and thermal stress distribution are obtained through calculation, and a finite element model of the superconducting magnet is obtained; superposing the two to construct a pre-stress field; performing electromagnetic field modeling on the model to obtain electromagnetic force distribution; further carrying out multi-field coupling stress analysis, and identifying a key stress plane with most concentrated stress; and finally, constructing a two-dimensional plane stress model based on the plane, and inputting winding and thermal stress as pre-stress and electromagnetic force as external load into the two-dimensional model so as to efficiently calculate final stress distribution of the superconducting magnet. Therefore, by implementing the method, the problems of unreliable stress calculation and low solving efficiency in the prior art can be solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of stress distribution calculation, and in particular to a stress distribution evaluation method and device for a superconducting magnet, an electronic device and a storage medium. BACKGROUND

[0002] The internal stress distribution of a superconducting magnet operating under extreme conditions such as strong magnetic fields, extremely low temperatures and large currents has a decisive influence on the structural integrity and superconducting performance of the magnet. If there is stress concentration or stress exceeding in a local area, it is easy to cause failure problems such as tape quenching and insulation damage, and further lead to magnet de-excitation and even permanent damage. Therefore, accurately evaluating the stress distribution of a superconducting magnet under actual working conditions, especially the superposition effect of multiple sources of stress, is of great significance for superconducting magnet design optimization, structural safety verification and service reliability guarantee.

[0003] The existing stress calculation methods mostly rely on static loading or simplified multi-field boundary conditions, which are difficult to accurately reflect the dynamic evolution process of the pre-stress in the winding process and the cooling process, and are easy to lead to unrealistic expression of the initial stress field, thereby affecting the reliability of the final stress calculation. In addition, the current full-scale simulation is mostly carried out by using a superconducting magnet finite element model, which is limited by factors such as complex magnet structure and multiple coupled loads, and has a large calculation scale and low solving efficiency. SUMMARY

[0004] The embodiments of the present application provide a stress distribution evaluation method and device for a superconducting magnet, an electronic device and a storage medium, which can solve the problems of unreliable stress calculation and low solving efficiency in the prior art.

[0005] An embodiment of the present application provides a stress distribution evaluation method for a superconducting magnet, comprising:

[0006] obtaining a superconducting magnet finite element model;

[0007] performing winding simulation on the superconducting magnet finite element model to calculate and generate a winding stress distribution of the superconducting magnet;

[0008] performing cooling simulation on the superconducting magnet finite element model with the winding stress distribution as an initial stress distribution to calculate and generate a thermal stress distribution of the superconducting magnet;

[0009] performing electromagnetic field modeling on the superconducting magnet finite element model to generate an electromagnetic force distribution of the superconducting magnet;

[0010] performing multi-field stress superposition analysis on the superconducting magnet finite element model to determine a maximum stress plane of the superconducting magnet under the coupling action of winding stress, thermal stress and electromagnetic force;

[0011] A two-dimensional plane stress model is established according to the maximum stress plane, and the winding stress distribution and the thermal stress distribution are taken as prestresses, and the electromagnetic force distribution is taken as an external load to input into the two-dimensional plane stress model, so that a final stress distribution of the superconducting magnet is generated.

[0012] Further, the superconducting magnet finite element model is obtained, including:

[0013] Obtaining the structural parameters and material attribute parameters of the superconducting magnet to be calculated stress;

[0014] According to the structural parameters of the superconducting magnet to be calculated stress, a three-dimensional geometric model of the superconducting magnet is constructed;

[0015] The three-dimensional geometric model is meshed to generate a meshed model of the superconducting magnet;

[0016] The material attribute parameters are configured to the meshed model to generate a superconducting magnet finite element model.

[0017] Further, the winding stress distribution is taken as the initial stress distribution, and the superconducting magnet finite element model is simulated to calculate the thermal stress distribution of the superconducting magnet, including:

[0018] Obtaining a target temperature value gradually decreasing in several temperature values;

[0019] For each target temperature value, the superconducting magnet finite element model is subjected to thermodynamic analysis to generate a thermal stress increment of each grid element of the superconducting magnet finite element model under the current target temperature value;

[0020] The thermal stress increments of each grid element of the superconducting magnet finite element model under all target temperature values are accumulated to generate a thermal stress distribution of the superconducting magnet.

[0021] Further, the superconducting magnet finite element model is subjected to multi-field stress superposition analysis to determine the maximum stress plane of the superconducting magnet under the coupling of winding stress, thermal stress and electromagnetic force, including:

[0022] Based on the superconducting magnet finite element model, the winding stress distribution, the thermal stress distribution and the electromagnetic force distribution are spatially superimposed to generate a total stress field;

[0023] Based on the Von Mises stress criterion, the equivalent stress value of each position in the total stress field is calculated;

[0024] All planes of the superconducting magnet are traversed to extract the equivalent stress peak value of each plane, and the plane of the equivalent stress peak value is taken as the maximum stress plane.

[0025] Furthermore, the step of establishing a two-dimensional plane stress model based on the plane of maximum stress, and inputting the winding stress distribution and thermal stress distribution as prestress and the electromagnetic force distribution as external load into the two-dimensional plane stress model to generate the final stress distribution of the superconducting magnet includes:

[0026] Extract the geometric data and boundary constraints of the plane with the maximum force.

[0027] Based on the geometric data and boundary constraints, a two-dimensional plane is constructed, and the mesh elements located on the plane of maximum stress in the finite element model of the superconducting magnet are projected onto the two-dimensional plane to generate a two-dimensional plane stress model.

[0028] The winding stress distribution and thermal stress distribution are mapped to a two-dimensional plane stress model using a stress interpolation algorithm to generate a two-dimensional prestress field, which is then input into the two-dimensional plane stress model as an initial stress condition.

[0029] The electromagnetic force distribution is numerically integrated along the normal of the two-dimensional plane to generate an equivalent surface force load, and the equivalent surface force load is input as an external load into the two-dimensional plane stress model.

[0030] The two-dimensional plane stress model is solved based on the preset plane stress constitutive equation to generate the final stress distribution of the superconducting magnet.

[0031] Furthermore, the plane stress constitutive equation is specifically as follows:

[0032]

[0033]

[0034]

[0035] Where, σ x σ represents the normal stress component in the x-direction within a two-dimensional plane. y τ represents the normal stress component in the y-direction within a two-dimensional plane. xy ε is the in-plane shear stress component; x ε represents the normal strain component in the x-direction; y γ represents the normal strain component in the y-direction; xy ν is the in-plane shear strain component; E is the elastic modulus of the material; v is the Poisson's ratio of the material.

[0036] Based on the above method embodiments, the present invention provides corresponding apparatus embodiments.

[0037] An embodiment of the present application provides a stress distribution evaluation device of a superconducting magnet, comprising: a finite element model acquisition module, a winding stress distribution generation module, a thermal stress distribution generation module, an electromagnetic force distribution generation module, a maximum stress plane determination module and a final stress distribution generation module.

[0038] The finite element model acquisition module is used for acquiring a finite element model of the superconducting magnet.

[0039] The winding stress distribution generation module is used for performing winding simulation on the finite element model of the superconducting magnet, and calculating and generating a winding stress distribution of the superconducting magnet.

[0040] The thermal stress distribution generation module is used for performing cooling simulation on the finite element model of the superconducting magnet with the winding stress distribution as an initial stress distribution, and calculating and generating a thermal stress distribution of the superconducting magnet.

[0041] The electromagnetic force distribution generation module is used for performing electromagnetic field modeling on the finite element model of the superconducting magnet, and generating an electromagnetic force distribution of the superconducting magnet.

[0042] The maximum stress plane determination module is used for performing multi-field stress superposition analysis on the finite element model of the superconducting magnet, and determining a maximum stress plane of the superconducting magnet under the coupling action of winding stress, thermal stress and electromagnetic force.

[0043] The final stress distribution generation module is used for establishing a two-dimensional plane stress model according to the maximum stress plane, and inputting the winding stress distribution and the thermal stress distribution as prestresses and the electromagnetic force distribution as an external load into the two-dimensional plane stress model, so as to generate a final stress distribution of the superconducting magnet.

[0044] Further, the stress distribution evaluation device of the superconducting magnet, the thermal stress distribution generation module is used for performing cooling simulation on the finite element model of the superconducting magnet with the winding stress distribution as an initial stress distribution, and calculating and generating a thermal stress distribution of the superconducting magnet, comprising:

[0045] Acquire a plurality of target temperature values gradually decreasing;

[0046] For each target temperature value, perform thermodynamic analysis on the finite element model of the superconducting magnet, and generate a thermal stress increment of each grid cell of the finite element model of the superconducting magnet under the current target temperature value;

[0047] Add up the thermal stress increments of each grid cell of the finite element model of the superconducting magnet under all target temperature values, and generate a thermal stress distribution of the superconducting magnet.

[0048] On the basis of the above-mentioned method embodiment, the present application correspondingly provides an electronic device embodiment.

[0049] An embodiment of the present application provides an electronic device, comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, and the processor implements the stress distribution evaluation method of the superconducting magnet in any of the method embodiments when the computer program is executed.

[0050] On the basis of the above-mentioned method embodiments, the present application correspondingly provides storage medium embodiments.

[0051] An embodiment of the present application provides a storage medium, which has a computer program stored thereon, wherein the computer program controls a device where the storage medium is located to execute the stress distribution evaluation method of the superconducting magnet in any of the method embodiments when the computer program is executed.

[0052] Compared with the prior art, the present application has the following beneficial effects:

[0053] Embodiments of the present application provide a stress distribution evaluation method, device, electronic equipment and storage medium of a superconducting magnet. The method first acquires a finite element model of the superconducting magnet, sequentially carries out winding simulation and cooling simulation, respectively obtains winding stress and thermal stress distribution, and superimposes thermal stress with winding stress as an initial condition to construct a more real pre-stress field; then, electromagnetic field modeling is performed to calculate electromagnetic force distribution; on this basis, multi-field coupling analysis is performed to determine the key plane where stress is most concentrated, and a two-dimensional plane stress model is constructed, the winding and thermal stress are taken as pre-stress, and the electromagnetic force is taken as external load input, thereby realizing fast and efficient calculation of the final stress of the superconducting magnet.

[0054] The present application improves the expression authenticity of the initial stress field from the source by constructing a complete multi-field loading process, sequentially performing winding process simulation and cooling process simulation to obtain dynamically evolving winding stress and thermal stress distribution, and inputting the two as pre-stress. The reliability of the final stress evaluation is improved. At the same time, by identifying the maximum stress plane under the action of multi-field coupling, and establishing a two-dimensional plane stress model based on the plane, the simulation scale is significantly reduced while ensuring the calculation accuracy, which helps to improve the efficiency of solving the stress distribution of the superconducting magnet. BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 is a flowchart of a stress distribution evaluation method of a superconducting magnet provided by an embodiment of the present application.

[0056] Figure 2 is a structural schematic diagram of a stress distribution evaluation device of a superconducting magnet provided by an embodiment of the present application. DETAILED DESCRIPTION

[0057] With reference to the drawings and the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0058] As shown in Figure 1 To solve the problems of unreliable stress calculation and low solving efficiency in the prior art, an embodiment of the present application provides a stress distribution evaluation method of a superconducting magnet, at least comprising the following steps:

[0059] Step S1, obtaining a finite element model of the superconducting magnet;

[0060] In a preferred embodiment, the step of obtaining the finite element model of the superconducting magnet comprises:

[0061] obtaining structure parameters and material attribute parameters of the superconducting magnet to be calculated;

[0062] constructing a three-dimensional geometric model of the superconducting magnet according to the structure parameters of the superconducting magnet to be calculated;

[0063] performing meshing on the three-dimensional geometric model to generate a meshed model of the superconducting magnet;

[0064] configuring the material attribute parameters to the meshed model to generate the finite element model of the superconducting magnet.

[0065] Specifically, the establishment of the finite element model of the superconducting magnet starts from the accurate digital mapping of the actual physical structure. First, the key structure parameters of the magnet to be calculated are obtained, including the number of winding layers, the cross-sectional size of the tape, the geometric topology of the skeleton (such as the inner diameter, the outer diameter, the end flange structure), and the thickness distribution of the insulation layer, etc. At the same time, the material attribute parameters are extracted, such as the elastic modulus, the Poisson's ratio, the thermal expansion coefficient of the superconducting tape, the thermal conductivity, the shear strength of the insulating material, etc. Based on these parameters, a three-dimensional geometric model is constructed through a parameterized modeling tool (such as COMSOL Multiphysics), to ensure that the geometric features of the winding stacking path, the interlayer contact surface and the support structure are consistent with the real magnet.

[0066] Subsequently, the three-dimensional geometric model is discretized by using an adaptive meshing technique: for high stress gradient regions (such as the curvature mutation at the winding end and the interlayer contact interface), local mesh refinement (mesh size can be refined to 0.1-0.5mm) is used to improve the stress resolution; for low stress regions (such as the main body of the skeleton), coarse mesh (mesh size 2-5mm) is used to control the calculation scale. After meshing, the material property parameters are assigned to the corresponding grid elements according to the region, for example, the anisotropic mechanical parameters are assigned to the superconducting tape region, and the orthotropic thermal conductivity is assigned to the insulation layer, thereby generating a finite element model that can bear multi-physical field coupling analysis.

[0067] Through parameterized modeling and adaptive meshing, a balance between geometric accuracy and computational efficiency is achieved, avoiding stress distribution distortion caused by geometric simplification; the fine configuration of material properties provides a physically realistic input condition for subsequent multi-field coupling simulation, ensuring the simulation credibility of the stress evolution path under the action of winding, cooling and electromagnetic load from the source.

[0068] Step S2, performing winding simulation on the superconducting magnet finite element model to calculate the winding stress distribution of the superconducting magnet;

[0069] Specifically, the winding simulation calculates the pre-stress distribution under the action of process tension by reproducing the actual winding process of the superconducting tape. Based on the finite element model, first, according to the actual winding parameters (such as initial tension value, interlayer tension decay rate and winding speed), a dynamically distributed tension load is applied layer by layer to simulate the tension gradient change of the tape from the outer layer to the inner layer during winding. In the contact interface between the tape and the skeleton, and the interlayer tape and the insulation material, the sliding, extrusion behavior and stress accumulation effect of the tape during winding are simulated by defining the friction coefficient and pressure transmission threshold. The mechanical parameters (such as elastic modulus, Poisson's ratio) of the tape are input into the material model and the creep characteristics are considered to reflect the deformation response under the action of continuous tension. The residual stress field after winding is calculated by the finite element solver, and the spatial distribution data of the axial tensile stress, interlayer contact pressure and local bending stress of the tape are output.

[0070] Through dynamic tension loading and contact nonlinear modeling, the gradient distribution characteristics of the pre-stress in the winding process are accurately captured, avoiding the uniformization error caused by the traditional static loading assumption; combined with the material creep effect and friction action, the interlayer stress accumulation law is truly reflected, providing a high-precision initial stress field for subsequent thermal-mechanical-electromagnetic multi-field coupling analysis.

[0071] Step S3, using the winding stress distribution as the initial stress distribution, performing cooling simulation on the superconducting magnet finite element model to calculate the thermal stress distribution of the superconducting magnet;

[0072] In one preferred embodiment, the cooling simulation of the superconducting magnet finite element model with the winding stress distribution as the initial stress distribution to calculate the thermal stress distribution of the superconducting magnet comprises:

[0073] Obtaining a target temperature value gradually decreasing from a plurality of temperature values;

[0074] For each target temperature value, performing a thermodynamic analysis on the superconducting magnet finite element model to generate a thermal stress increment of each grid cell of the superconducting magnet finite element model at the current target temperature value;

[0075] Accumulating the thermal stress increments of each grid cell of the superconducting magnet finite element model at all target temperature values to generate the thermal stress distribution of the superconducting magnet.

[0076] Specifically, the thermal stress calculation needs to simulate the stress accumulation process of the superconducting magnet from the initial temperature (such as room temperature 300K) to the target low temperature (such as 4.2K) step by step. First, the cooling process is divided into a plurality of discrete temperature points (for example, every 50K is a temperature step), and a thermal-mechanical coupling analysis is performed on each temperature step based on the material thermal expansion coefficient and the temperature-dependent elastic modulus, to calculate the thermal strain increment of the magnet due to temperature change, and convert it to thermal stress increment through the material constitutive relationship. The stress increment of each temperature step is accumulated one by one, and the stress relaxation effect caused by plastic deformation is corrected according to the low-temperature yield strength of the material, to finally generate the thermal stress distribution under the complete cooling path.

[0077] Step S4, performing electromagnetic field modeling on the superconducting magnet finite element model to generate an electromagnetic force distribution of the superconducting magnet;

[0078] Specifically, the electromagnetic field modeling calculates the electromagnetic force distribution on the tape by reproducing the current-magnetic field interaction of the superconducting magnet under the excitation working condition. Based on the finite element model, first define the current load parameters in the superconducting tape area, including the excitation current amplitude (such as 20kA), the current loading path (such as uniformly distributed along the axial direction of the tape), and the current variation curve with time (such as linearly increasing to the target value). Combined with the electromagnetic properties of superconducting materials, the spatial distribution of the magnetic field is solved by coupling Maxwell's equations and the superconducting constitutive equation. According to the Lorentz force formula F = J x B (where J is the current density and B is the magnetic induction intensity), the volume force density of each grid cell of the tape under the action of the magnetic field is calculated, and the electromagnetic force distribution per unit length is generated by area integration along the tape.

[0079] Through magnetic field-current coupling iteration and Lorentz force refinement calculation, the electromagnetic force gradient distribution of the superconducting tape under high field is accurately captured, providing high credibility load input for multi-field coupling.

[0080] Step S5, performing multi-field stress superposition analysis on the superconducting magnet finite element model to determine the maximum stress plane of the superconducting magnet under the coupling of winding stress, thermal stress and electromagnetic force;

[0081] In a preferred embodiment, the multi-field stress superposition analysis on the superconducting magnet finite element model to determine the maximum stress plane of the superconducting magnet under the coupling of winding stress, thermal stress and electromagnetic force includes:

[0082] Based on the superconducting magnet finite element model, the winding stress distribution, the thermal stress distribution and the electromagnetic force distribution are spatially superimposed to generate a total stress field;

[0083] Based on the Von Mises stress criterion, the equivalent stress value of each position in the total stress field is calculated;

[0084] Traverse all planes of the superconducting magnet, extract the equivalent stress peak value of each plane, and take the plane of the equivalent stress peak value as the maximum stress plane.

[0085] Specifically, by superimposing the winding stress, the thermal stress and the electromagnetic force grid by grid according to the actual values, the total stress field data is generated, for example, the total stress of a strip unit winding tensile stress (200 MPa), thermal shrinkage stress (150 MPa) and electromagnetic shear stress (30 MPa) is 380 MPa. Based on the Von Mises stress criterion, the equivalent stress value of each unit is calculated (such as the calculation result of a unit is 420 MPa), which directly reflects the material yield risk. Then, using the finite element post-processing tool, dense parallel sections are generated along the winding axis direction (for example, one section is generated every 5 mm), the maximum equivalent stress value in each section is extracted, and finally the section with the highest peak value is selected as the maximum stress plane. This method directly accumulates stress data and selects engineering criteria, providing accurate input for subsequent dimension reduction modeling.

[0086] Step S6, establishing a two-dimensional plane stress model according to the maximum stress plane, and inputting the winding stress distribution and the thermal stress distribution as prestress and the electromagnetic force distribution as external load into the two-dimensional plane stress model to generate the final stress distribution of the superconducting magnet.

[0087] In a preferred embodiment, the two-dimensional plane stress model is established according to the maximum stress plane, and the winding stress distribution and the thermal stress distribution are inputted as prestress and the electromagnetic force distribution is inputted as external load into the two-dimensional plane stress model to generate the final stress distribution of the superconducting magnet, including:

[0088] Extracting the geometric data and boundary constraint conditions of the maximum stress plane;

[0089] According to the geometric data and the boundary constraint condition, a two-dimensional plane is constructed, and grid elements located on the maximum stress plane in the superconducting magnet finite element model are projected to the two-dimensional plane to generate a two-dimensional plane stress model;

[0090] The winding stress distribution and the thermal stress distribution are mapped to the two-dimensional plane stress model by a stress interpolation algorithm to generate a two-dimensional prestress field, and the two-dimensional prestress field is input as an initial stress condition to the two-dimensional plane stress model;

[0091] The electromagnetic force distribution is numerically integrated along the normal direction of the two-dimensional plane to generate an equivalent surface force load, and the equivalent surface force load is input as an external load to the two-dimensional plane stress model;

[0092] The two-dimensional plane stress model is solved based on a preset plane stress constitutive equation to generate a final stress distribution of the superconducting magnet.

[0093] Specifically, geometric data (including plane contour coordinates, normal direction, and boundary topological relationship) and actual constraint conditions (such as a certain side boundary fixed support and another side free end displacement limitation) of the maximum stress plane are extracted, and a two-dimensional plane geometry strictly aligned with the three-dimensional model is constructed by using a parameterized modeling tool. The grid node coordinates of the three-dimensional model located on the plane are orthogonally projected to the two-dimensional plane along the normal direction to generate a two-dimensional plane stress model grid.

[0094] Three-dimensional winding stress and thermal stress are mapped to the corresponding elements of the two-dimensional model by a bilinear stress interpolation algorithm to generate a two-dimensional prestress field data file, and the prestress field is loaded as an initial stress to the two-dimensional model by a finite element pre-processing module to ensure that the stress boundary and the geometric constraint are matched.

[0095] Gaussian numerical integration is performed on the three-dimensional electromagnetic force distribution along the normal direction of the two-dimensional plane to convert the volume force into an equivalent surface force load, and the total force conservation before and after integration is verified by a post-processing script, and finally the equivalent surface force is applied to the corresponding boundary of the two-dimensional model.

[0096] Based on a preset plane stress constitutive equation, finite element solving is performed to output the final stress distribution of the two-dimensional model.

[0097] In a preferred embodiment, the plane stress constitutive equation is specifically:

[0098]

[0099]

[0100]

[0101] wherein σ xσ represents the normal stress component in the x-direction within a two-dimensional plane. y τ represents the normal stress component in the y-direction within a two-dimensional plane. xy ε is the in-plane shear stress component; x ε represents the normal strain component in the x-direction; y γ represents the normal strain component in the y-direction; xy ν is the in-plane shear strain component; E is the elastic modulus of the material; v is the Poisson's ratio of the material.

[0102] like Figure 2 As shown, an embodiment of the present invention provides a stress distribution evaluation device for a superconducting magnet, including: a finite element model acquisition module, a winding stress distribution generation module, a thermal stress distribution generation module, an electromagnetic force distribution generation module, a maximum force plane determination module, and a final stress distribution generation module;

[0103] The finite element model acquisition module is used to acquire the finite element model of the superconducting magnet;

[0104] The winding stress distribution generation module is used to perform winding simulation on the finite element model of the superconducting magnet and calculate and generate the winding stress distribution of the superconducting magnet.

[0105] The thermal stress distribution generation module is used to perform a cooling simulation on the finite element model of the superconducting magnet, using the winding stress distribution as the initial stress distribution, and to calculate and generate the thermal stress distribution of the superconducting magnet.

[0106] The electromagnetic force distribution generation module is used to perform electromagnetic field modeling on the finite element model of the superconducting magnet and generate the electromagnetic force distribution of the superconducting magnet.

[0107] The maximum stress plane determination module is used to perform multi-field stress superposition analysis on the finite element model of the superconducting magnet to determine the maximum stress plane of the superconducting magnet under the action of winding stress, thermal stress and electromagnetic force coupling.

[0108] The final stress distribution generation module is used to establish a two-dimensional plane stress model based on the maximum stress plane, and input the winding stress distribution and thermal stress distribution as prestress and the electromagnetic force distribution as external load into the two-dimensional plane stress model to generate the final stress distribution of the superconducting magnet.

[0109] In a preferred embodiment, the stress distribution evaluation device for the superconducting magnet includes a thermal stress distribution generation module, used to perform a cooling simulation on the finite element model of the superconducting magnet using the winding stress distribution as the initial stress distribution, and to calculate and generate the thermal stress distribution of the superconducting magnet, including:

[0110] Obtain a target temperature value that gradually decreases from several temperature values;

[0111] performing a thermal stress increment analysis on the superconducting magnet finite element model at each target temperature value to generate thermal stress increments of each grid cell of the superconducting magnet finite element model at the current target temperature value;

[0112] accumulating the thermal stress increments of each grid cell of the superconducting magnet finite element model at all target temperature values to generate a thermal stress distribution of the superconducting magnet.

[0113] It should be noted that the above-described embodiments of the device correspond to the above-described embodiments of the application, and can implement the stress distribution evaluation method of the superconducting magnet according to any one of the above-described embodiments of the application. In addition, the above-described embodiments of the device are merely illustrative, and the modules described as separate components can or can not be physically separated, and the components displayed as modules can or can not be physical units, i.e., they can be located in one place or distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the present embodiment. In addition, in the drawings of the device embodiments provided by the present application, the connection relationship between the modules indicates that there is a communication connection between them, which can be implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement it without creative labor.

[0114] On the basis of the above-described method embodiments of the application, an electronic device embodiment is correspondingly provided.

[0115] An electronic device is provided in an embodiment of the application, which includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, the stress distribution evaluation method of the superconducting magnet according to any one of the above-described embodiments of the application is implemented, or when the processor executes the computer program, the functions of the modules in the above-described device embodiments are implemented.

[0116] For example, the computer program can be divided into one or more modules, which are stored in the memory and executed by the processor to complete the application. The one or more modules can be a series of computer program instruction segments that can complete a specific function, which are used to describe the execution process of the computer program in the terminal device.

[0117] The terminal device can be a desktop computer, a notebook computer, a palm computer, a cloud server, and other computing devices. The terminal device can include, but is not limited to, a processor and a memory.

[0118] The processor can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor. The processor is a control center of the terminal device, and connects all parts of the terminal device through various interfaces and lines.

[0119] The memory can be used to store the computer program and / or modules, and the processor realizes various functions of the terminal device by running or executing the computer program and / or modules stored in the memory, and calling data stored in the memory. The memory can mainly include a program storage area and a data storage area. The program storage area can store an operating system, at least one application program required by a function, etc.; and the data storage area can store data created according to the use of the mobile phone, etc. In addition, the memory can include a high-speed random access memory, and can also include a nonvolatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, at least one disk storage device, a flash memory device, or other volatile solid-state memory devices.

[0120] On the basis of the above-mentioned method embodiment, the application further provides a storage medium embodiment;

[0121] Another embodiment of the application provides a storage medium, which comprises a stored computer program, wherein when the computer program runs, the device where the storage medium is located performs the stress distribution evaluation method of any one of the superconducting magnets described above.

[0122] The storage medium is a computer readable storage medium, and the computer program includes computer program code in the form of source code, object code, an executable file, or some intermediate form, etc. The computer readable medium can include any entity or device capable of carrying the computer program code, a recording medium, a U disk, a mobile hard disk, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, a software distribution medium, etc.

[0123] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0124] The above is the preferred embodiment of the present application. It should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which are also considered within the scope of protection of the present application.

Claims

1. A method for evaluating the stress distribution of a superconducting magnet, characterized in that, include: Obtain the finite element model of the superconducting magnet; The winding simulation of the superconducting magnet finite element model was performed to calculate and generate the winding stress distribution of the superconducting magnet; Using the winding stress distribution as the initial stress distribution, a cooling simulation is performed on the finite element model of the superconducting magnet to calculate and generate the thermal stress distribution of the superconducting magnet; Electromagnetic field modeling is performed on the finite element model of the superconducting magnet to generate the electromagnetic force distribution of the superconducting magnet; Multi-field stress superposition analysis was performed on the finite element model of the superconducting magnet to determine the maximum stress plane of the superconducting magnet under the coupling of winding stress, thermal stress and electromagnetic force. A two-dimensional plane stress model is established based on the plane of maximum stress, and the winding stress distribution and thermal stress distribution are used as prestresses, while the electromagnetic force distribution is used as an external load input to the two-dimensional plane stress model, thereby generating the final stress distribution of the superconducting magnet.

2. The method for evaluating the stress distribution of a superconducting magnet as described in claim 1, characterized in that, The process of obtaining the finite element model of the superconducting magnet includes: Obtain the structural parameters and material property parameters of the superconducting magnet whose stress is to be calculated; Based on the structural parameters of the superconducting magnet whose stress is to be calculated, a three-dimensional geometric model of the superconducting magnet is constructed. The three-dimensional geometric model is meshed to generate a meshed model of the superconducting magnet; The material property parameters are configured into the meshed model to generate a finite element model of a superconducting magnet.

3. The method for evaluating the stress distribution of a superconducting magnet as described in claim 1, characterized in that, The step of using the winding stress distribution as the initial stress distribution to perform a cooling simulation on the finite element model of the superconducting magnet, and calculating the thermal stress distribution of the superconducting magnet, includes: Obtain a target temperature value that gradually decreases from several temperature values; For each target temperature value, a thermodynamic analysis is performed on the finite element model of the superconducting magnet to generate the thermal stress increment of each mesh element of the finite element model of the superconducting magnet at the current target temperature value; The thermal stress increments of each mesh element in the finite element model of the superconducting magnet at all target temperature values ​​are accumulated to generate the thermal stress distribution of the superconducting magnet.

4. The method for evaluating the stress distribution of a superconducting magnet as described in claim 3, characterized in that, The multi-field stress superposition analysis of the finite element model of the superconducting magnet to determine the maximum stress plane of the superconducting magnet under the coupling of winding stress, thermal stress, and electromagnetic force includes: Based on the finite element model of the superconducting magnet, the winding stress distribution, thermal stress distribution and electromagnetic force distribution are spatially superimposed to generate the total stress field; Based on the Von Mises stress criterion, the equivalent stress values ​​at each location in the total stress field are calculated; Traverse all planes of the superconducting magnet, extract the peak equivalent stress of each plane, and take the plane with the peak equivalent stress as the plane with the maximum force.

5. The method for evaluating the stress distribution of a superconducting magnet as described in claim 4, characterized in that, The step of establishing a two-dimensional plane stress model based on the plane of maximum stress, and inputting the winding stress distribution and thermal stress distribution as prestress and the electromagnetic force distribution as external load into the two-dimensional plane stress model to generate the final stress distribution of the superconducting magnet includes: Extract the geometric data and boundary constraints of the plane with the maximum force. Based on the geometric data and boundary constraints, a two-dimensional plane is constructed, and the mesh elements located on the plane of maximum stress in the finite element model of the superconducting magnet are projected onto the two-dimensional plane to generate a two-dimensional plane stress model. The winding stress distribution and thermal stress distribution are mapped to a two-dimensional plane stress model using a stress interpolation algorithm to generate a two-dimensional prestress field, which is then input into the two-dimensional plane stress model as an initial stress condition. The electromagnetic force distribution is numerically integrated along the normal of the two-dimensional plane to generate an equivalent surface force load, and the equivalent surface force load is input as an external load into the two-dimensional plane stress model. The two-dimensional plane stress model is solved based on the preset plane stress constitutive equation to generate the final stress distribution of the superconducting magnet.

6. The method for evaluating the stress distribution of a superconducting magnet as described in claim 5, characterized in that, The plane stress constitutive equation is as follows: Where, σ x σ represents the normal stress component in the x-direction within a two-dimensional plane. y τ represents the normal stress component in the y-direction within a two-dimensional plane. xy ε is the in-plane shear stress component; x ε represents the normal strain component in the x-direction; y γ represents the normal strain component in the y-direction; xy ν is the in-plane shear strain component; E is the elastic modulus of the material; v is the Poisson's ratio of the material.

7. A stress distribution evaluation device for a superconducting magnet, characterized in that, include: The module includes: finite element model acquisition module, winding stress distribution generation module, thermal stress distribution generation module, electromagnetic force distribution generation module, maximum stress plane determination module, and final stress distribution generation module. The finite element model acquisition module is used to acquire the finite element model of the superconducting magnet; The winding stress distribution generation module is used to perform winding simulation on the finite element model of the superconducting magnet and calculate and generate the winding stress distribution of the superconducting magnet. The thermal stress distribution generation module is used to perform a cooling simulation on the finite element model of the superconducting magnet, using the winding stress distribution as the initial stress distribution, and to calculate and generate the thermal stress distribution of the superconducting magnet. The electromagnetic force distribution generation module is used to perform electromagnetic field modeling on the finite element model of the superconducting magnet and generate the electromagnetic force distribution of the superconducting magnet. The maximum stress plane determination module is used to perform multi-field stress superposition analysis on the finite element model of the superconducting magnet to determine the maximum stress plane of the superconducting magnet under the action of winding stress, thermal stress and electromagnetic force coupling. The final stress distribution generation module is used to establish a two-dimensional plane stress model based on the maximum stress plane, and input the winding stress distribution and thermal stress distribution as prestress and the electromagnetic force distribution as external load into the two-dimensional plane stress model to generate the final stress distribution of the superconducting magnet.

8. The stress distribution evaluation device for superconducting magnets as described in claim 7, characterized in that, A thermal stress distribution generation module is used to perform a cooling simulation on the finite element model of the superconducting magnet, using the winding stress distribution as the initial stress distribution, and to calculate and generate the thermal stress distribution of the superconducting magnet, including: Obtain a target temperature value that gradually decreases from several temperature values; For each target temperature value, a thermodynamic analysis is performed on the finite element model of the superconducting magnet to generate the thermal stress increment of each mesh element of the finite element model of the superconducting magnet at the current target temperature value; The thermal stress increments of each mesh element in the finite element model of the superconducting magnet at all target temperature values ​​are accumulated to generate the thermal stress distribution of the superconducting magnet.

9. An electronic device, characterized in that, The system includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor, when executing the computer program, implements the stress distribution assessment method for a superconducting magnet as described in any one of claims 1 to 6.

10. A storage medium, characterized in that, The storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device containing the storage medium to perform the stress distribution assessment method for a superconducting magnet as described in any one of claims 1 to 6.

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