Material dynamic mechanical behavior simulation method and system based on LS-DYNA

Abstract

The invention provides a material dynamic mechanical behavior simulation method and system based on LS-DYNA, and relates to the technical field of material simulation analysis methods. The method comprises the following steps: compiling a viscous-hyperelastic constitutive mathematical model into a UMAT subprogram, and embedding the UMAT subprogram into a solver of LS-DYNA software; the method comprises the following steps: carrying out finite element mesh generation on a geometric simulation model of a high polymer material sample, and generating a k file according to the characteristics of a high polymer material, keywords of a defined UMAT subprogram and parameter assignment of a viscous-hyperelastic constitutive mathematical model; and calling a solver of the LS-DYNA software according to the keyword of the UMAT subprogram, and calculating a k file to obtain a simulation result. According to the method, the dynamic mechanical response of the high polymer material can be predicted with high precision, the simulation precision of LS-DYNA software is improved, and the method is widely applicable to dynamic response simulation of materials such as rubber, a polyurea coating and a polyether polyurethane solid propellant in an impact environment.

Description

Technical Field

[0001] This specification relates to the technical field of material simulation analysis methods, and more specifically, to a material dynamic mechanical behavior simulation method and system based on LS-DYNA. Background Technology

[0002] Polymer materials have wide applications not only in daily civilian life but also play a crucial role in aerospace and military industries. Hyperelasticity and viscoelasticity are two typical mechanical properties of polymer materials. Hyperelasticity is characterized by high elongation and the ability to essentially recover its original length after deformation. The most classic example is the hyperelastic constitutive model based on the strain energy function proposed by RSRivlin et al. The viscoelastic mechanical response characteristics of polymer materials are complex. Viscoelasticity refers to the mechanical response of materials that combines the characteristics of elastic solids and viscous fluids to external forces. The properties of viscoelastic materials are strongly time-dependent. The strain of a viscoelastic body depends not only on the magnitude of the applied force but also on the loading history and the duration of the force's action. This time dependence of viscoelastic materials is ultimately reflected in several mechanical properties of viscous materials, including relaxation, creep, recovery, and strain rate effects. In mechanical constitutive model studies, spring models and sticky pot models are commonly used to represent elastic and viscous responses, respectively.

[0003] Many polymer materials, such as rubber, polyurea coatings, and polyether polyurethane solid propellants, exhibit both rate-dependent viscoelasticity and deformation-recoverable hyperelasticity under impact conditions. However, existing material model libraries lack constitutive models that can simultaneously describe both viscosity and hyperelasticity. Therefore, current simulation software cannot predict the viscoelastic mechanical responses of polymer materials under different force conditions. Summary of the Invention

[0004] The purpose of this specification is to provide a simulation method for the dynamic mechanical behavior of materials based on LS-DYNA, which can solve the following problems.

[0005] The embodiments described in this specification are implemented as follows:

[0006] On the one hand, this specification provides a simulation method for the dynamic mechanical behavior of materials based on LS-DYNA, which mainly includes:

[0007] Construct a constitutive mathematical model of viscoelasticity;

[0008] The aforementioned viscoelastic constitutive mathematical model was written as a UMAT subroutine and embedded into the solver of the LS-DYNA software;

[0009] Import the constructed geometric simulation model of the polymer material sample into LS-DYNA software;

[0010] By performing finite element mesh generation on the geometric simulation model of the polymer material sample, and generating a k file based on the properties of the polymer material, the keywords of the defined UMAT subroutine, and the parameter assignment of the viscoelastic-hyperelastic constitutive mathematical model, the k file contains the calculation command file for each finite element information of the geometric simulation model. The finite element information includes at least the characteristic information of the finite elements, and the characteristics of the polymer material include the deformation characteristics of the polymer material.

[0011] Based on the keywords of the UMAT subroutine, the solver of the LS-DYNA software is called to calculate the k-file and obtain the simulation results of the dynamic mechanical behavior of the polymer material sample.

[0012] On the other hand, this specification provides a material dynamic mechanical behavior simulation system based on LS-DYNA, which mainly includes:

[0013] Modules are used to construct constitutive mathematical models of viscoelasticity;

[0014] An embedded module is used to write the viscoelastic-hyperelastic constitutive mathematical model into a UMAT subroutine and embed it into the solver of the LS-DYNA software;

[0015] The import module is used to import the geometric simulation model of the constructed polymer material sample into the LS-DYNA software;

[0016] The generation module is used to perform finite element mesh generation on the geometric simulation model of the polymer material sample, and generate a k file based on the properties of the polymer material, the keywords of the defined UMAT subroutine, and the parameter assignment of the viscoelastic-hyperelastic constitutive mathematical model. The k file contains the calculation command file of each finite element information of the geometric simulation model. The finite element information includes at least the characteristic information of the finite elements, and the characteristics of the polymer material include the deformation characteristics of the polymer material.

[0017] The simulation module is used to call the solver of the LS-DYNA software according to the keywords of the UMAT subroutine, calculate the k-file, and obtain the simulation results of the dynamic mechanical behavior of the polymer material sample.

[0018] The embodiments described in this specification have at least the following advantages or beneficial effects:

[0019] This LS-DYNA-based simulation method for material dynamic mechanical behavior embeds the constructed viscoelastic constitutive mathematical model into the solver of the LS-DYNA software as a program. Based on the defined k-file, the stress-strain relationship of the polymer material sample is calculated to obtain the simulation results, namely, the viscoelastic mechanical response of the polymer material under different force environments. It is evident that this secondary development of the LS-DYNA software can accurately predict the dynamic mechanical response of polymer materials that simultaneously describe viscous and hyperelastic properties, thereby significantly improving the simulation accuracy of the LS-DYNA software. This method is widely applicable to the dynamic response simulation of materials such as rubber, polyurea coatings, and polyether polyurethane solid propellants under impact environments. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this specification, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this specification and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart illustrating the LS-DYNA-based simulation method for material dynamic mechanical behavior provided in this manual.

[0022] Figure 2 This is another flowchart illustrating the LS-DYNA-based material dynamic mechanical behavior simulation method provided in this manual;

[0023] Figure 3 A schematic diagram of the finite element mesh generation for the geometric simulation model of the polymer material sample provided in this specification;

[0024] Figure 4 This is a schematic diagram illustrating the definition of keywords for a fixed rigid wall provided in this manual.

[0025] Figure 5 This is a schematic diagram illustrating the definition of keywords for a compression-moving rigid wall provided in this specification;

[0026] Figure 6 The custom material keyword provided in this specification is *MAT_USER_DEFINED_MATERIAL_MODELS;

[0027] Figure 7 This is a schematic diagram illustrating the comparison results provided in this specification;

[0028] Figure 8 This is a schematic diagram of the LS-DYNA-based material dynamic mechanical behavior simulation system provided in this manual. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments in this specification clearer, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Generally, the components of the embodiments of this specification described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0030] Please refer to Figures 1 to 7 One embodiment of this specification provides a simulation method for the dynamic mechanical behavior of materials based on LS-DYNA, which mainly includes:

[0031] Step 102: Construct a viscous-hyperelastic constitutive mathematical model;

[0032] Step 104: Compile the viscoelastic-hyperelastic constitutive mathematical model into a UMAT subroutine and embed it into the solver of the LS-DYNA software;

[0033] Step 106: Import the constructed geometric simulation model of the polymer material sample into LS-DYNA software;

[0034] Step 108: By performing finite element mesh generation on the geometric simulation model of the polymer material sample, and generating a k file based on the properties of the polymer material, the keywords of the defined UMAT subroutine, and the parameter assignment of the viscoelastic-hyperelastic constitutive mathematical model, the k file contains the calculation command file for each finite element information of the geometric simulation model. The finite element information includes at least the characteristic information of the finite elements, and the characteristics of the polymer material include the deformation characteristics of the polymer material.

[0035] Step 110: According to the keywords of the UMAT subroutine, call the solver of the LS-DYNA software to calculate the k file and obtain the simulation results of the dynamic mechanical behavior of the polymer material sample.

[0036] In this embodiment, the k file contains the calculation command file for all finite element information of the LS-DYNA software, including node information, element information, contact load definition, material model definition, etc.

[0037] Among them, node information includes node coordinates, and unit information includes unit type, node number of the constituent unit, and component number to which the unit belongs.

[0038] In this embodiment, the node coordinates mentioned above are the finite element mesh coordinates of the simulation model.

[0039] Specifically, the constructed viscoelastic constitutive mathematical model is programmed and embedded into the solver of the LS-DYNA software. Based on the defined k-file, the stress-strain relationship of the polymer material sample is calculated, thereby obtaining the simulation results, which are the viscoelastic mechanical response results of the polymer material under different force environments. It is evident that the above-mentioned secondary development of the LS-DYNA software can accurately predict the dynamic mechanical response of polymer materials that simultaneously describe viscous and hyperelastic properties, thus significantly improving the simulation accuracy of the LS-DYNA software. In this embodiment, the above simulation method is widely applicable to the dynamic response simulation of materials such as rubber, polyurea coatings, and polyether polyurethane solid propellants under impact environments.

[0040] In this embodiment, the polymer material sample is either a physical object or a structure designed according to the material's properties. The geometric simulation model can be constructed using mechanical design software, such as Creo software.

[0041] In this embodiment, the characteristics of the polymer material include the loading conditions and boundary conditions of the polymer material. The loading conditions are the relationship between the force and deformation of the polymer material, and the boundary conditions are the force constraint conditions of the polymer material.

[0042] In this embodiment, the loading condition can be a speed-stretching condition or a deformation condition, and the boundary condition is a material constraint condition for the polymer material.

[0043] In this embodiment, one specific implementation of step 102 is as follows:

[0044] Step 122: Obtain the Maxwell model of the linear spring and the sticky pot in series and the Rivlin hyperelastic constitutive model of the power series N=2 of the strain energy function equation;

[0045] Step 124: Construct the viscous-hyperelastic constitutive mathematical model based on the Maxwell model of the linear spring and the sticky pot in series and the Rivlin hyperelastic constitutive model of the power series N=2 of the strain energy function equation.

[0046] In this embodiment, the viscoelastic constitutive mathematical model is:

[0047]

[0048] Where λ = 1 - ε is the tensile ratio in the direction of uniaxial compressive load; σ represents the material stress, and ε represents the material strain. C represents the strain rate, τ represents the time integral variable, and C represents the strain rate. 10 C 20 C 11 C 01 C02 θ1 represents the Rivlin hyperelastic coefficient for a power series N=2, E1 represents the elastic coefficient for viscoelastic properties, and θ1 represents the viscosity coefficient for viscoelastic properties.

[0049] Specifically, the above-mentioned viscous-hyperelastic constitutive mathematical model is constructed as follows:

[0050] The constitutive equation of the Maxwell model of the above-mentioned linear spring and sticky pot in series is:

[0051]

[0052] Where, σ v This represents the Cauchy stress in the viscoelastic portion.

[0053] Under large deformation conditions, the second Piola-Kirchhoff stress S and Green's strain E are uniformly used to represent the stress-strain relationship. The constitutive equation of the Maxwell model with the linear spring and the sticky pot in series can be rewritten as:

[0054]

[0055] Among them, S v E(t) represents the second Piola-Kirchhoff stress of the viscoelastic component as a function of time, and E(r) represents the Green strain as a function of time.

[0056] During the incremental time interval t→t+Δt, the stress increment ΔS of the viscoelastic component v (t+Δt) is:

[0057]

[0058] Extended to three-dimensional form ΔS ij v (t+Δt) is, in other words:

[0059]

[0060] Where i, j, k, l are tensor indices, and ΔS ij v (t+Δt) represents the three-dimensional form of the stress increment of the viscoelastic component at time t+Δt, A ijkl Here is the stiffness matrix, ΔE kl S represents the three-dimensional form of the strain increment during the time interval t→t+Δt. ij v (t) represents the three-dimensional stress form of the viscoelastic component at time t, which is:

[0061]

[0062] In this embodiment, the hyperelastic strain energy function of the Rivlin hyperelastic constitutive model with a power series N=2 of strain energy function equation is:

[0063] W=C 10 (I1-3)+C 01 (I²⁻³) + C 20 (I1-3) 2 +C 02 (I2-3) 2 +C 11 (I1-3)(I2-3)+W H (I3)

[0064]

[0065] Where I1, I2, and I3 are the three principal invariants of the Cauchy-Green deformation tensor, and D1 and D2 are the hyperelastic coefficients C. 10 C 20 C 11 C 01 C 02 The complex polynomial, strain energy density function W with respect to Green's strain components E ij The partial derivatives yield:

[0066]

[0067] Among them, S ij h The second Piola-Kirchhoff stress three-dimensional component is the hyperelastic part.

[0068] In this embodiment, the Green strain component E ij With the right Cauchy-Green deformation tensor C ij The relationship between them is:

[0069]

[0070] Then we have:

[0071]

[0072] It is easy to know:

[0073]

[0074] It can be obtained that the second Piola-Kirchhoff stress component S of the hyperelastic part ij h for:

[0075]

[0076] in:

[0077]

[0078]

[0079] In the formula, v is Poisson's ratio.

[0080] In this embodiment, the second Piola-Kirchhoff stress component S of the viscoelastic constitutive model is... ij For the hyperelastic stress component S ij h and viscoelastic stress component S ij v sum:

[0081] S ij =S ij h +S ij v

[0082] The total Cauchy stress component σ converted to a viscoelastic constitutive model kl Represented as:

[0083]

[0084] Where i, j, k, l are tensor indices, F ki F jl Let J = det(F) be the component of the deformed gradient matrix F, and let J = det(F) be the Jacobian determinant of the deformed gradient matrix F.

[0085] In this embodiment, one specific implementation of step 104 is as follows:

[0086] Step 132: Use FORTRAN language to write the viscoelastic-hyperelastic constitutive mathematical model into the UMAT subroutine;

[0087] Step 134: Open the dyna.f file in the lib folder of the LS-DYNA software on the Microsoft Visual C++ platform, and write the UMAT subroutine into the subroutine umat41() program segment;

[0088] Step 136: Compile the subroutine umat41() program segment using the Intel(R) Fortran Compiler to obtain the lsdyna_visco_hyper.exe executable solver embedded with the UMAT subroutine.

[0089] In this embodiment, the three software programs LS-DYNA, Intel(R) Fortran Compiler, and Microsoft Visual C++ are associated in the manner described above to provide an environment for compiling UMAT subroutines.

[0090] In this embodiment, the UMAT subroutine can be embedded into the LS-DYNA software in the above manner to achieve the purpose of secondary development of the LS-DYNA software.

[0091] In this embodiment, one specific implementation of step 106 is as follows:

[0092] Step 142: Using model design software, construct a geometric simulation model of the polymer material sample based on the characteristics and requirements of the polymer material;

[0093] Step 144: Import the geometric simulation model of the polymer material sample into the preprocessing interface LS-PrePost of LS-DYNA software.

[0094] In this embodiment, the geometric simulation model of the polymer material sample is stored in .igs file format, and it is imported into the preprocessing interface LS-PrePost of the LS-DYNA software in .igs file format.

[0095] In this embodiment, the keywords of the UMAT subroutine include keywords for compressing rigid walls and compression speed, material keywords, calculation time keywords, and calculation step size keywords.

[0096] In this embodiment, one specific implementation of step 108 is as follows:

[0097] Step 152: Perform finite element mesh generation on the geometric simulation model of the polymer material sample to obtain multiple finite element models;

[0098] Step 154: Define the keywords for each finite element, and the keywords for the finite elements correspond to the definitions of the UMAT subroutines;

[0099] Step 156: Assign values ​​to the parameters in the viscoelastic-hyperelastic constitutive mathematical model;

[0100] Step 158: Generate the k-file based on the defined keywords of the finite element method, the parameter assignments of the viscoelastic-hyperelastic constitutive mathematical model, and the properties of the polymer material. In this embodiment, please refer to... Figure 3 The above finite element mesh can be a hexahedral finite element mesh.

[0101] In this embodiment, the material keyword *MAT_USER_DEFINED_MATERIAL_MODELS corresponding to the above UMAT subroutine definition is set to complete the writing of the above k file.

[0102] In this embodiment, by generating k-files, different k-files can be generated for different polymer material samples, or k-files with different parameters can be generated. The simulation results can then be calculated using the UMAT subroutine, resulting in higher simulation accuracy.

[0103] In this embodiment, after step 110, the following steps are also included:

[0104] Step 162: Compare the simulation results of the dynamic mechanical behavior of the polymer material sample with the stress-strain theoretical data of the same polymer material sample to obtain the comparison structure;

[0105] Step 164: Based on the comparison results, verify the simulation results of the dynamic mechanical behavior of the polymer material sample.

[0106] In this embodiment, the correctness, effectiveness, and reliability of the above method can be effectively verified through the above method.

[0107] In this embodiment, simulation and theoretical calculations were performed on the same polymer material sample. The comparison results are detailed below. Figure 7 As can be seen, the theoretical data and simulation results have good data consistency, which verifies the correctness of the above method.

[0108] Please refer to Figure 8 Another embodiment of this specification provides a material dynamic mechanical behavior simulation system based on LS-DYNA, which mainly includes:

[0109] Module 202 is used to construct a viscous-hyperelastic constitutive mathematical model;

[0110] Embedded module 204 is used to write the viscoelastic-hyperelastic constitutive mathematical model into a UMAT subroutine and embed it into the solver of LS-DYNA software;

[0111] Import module 206 is used to import the geometric simulation model of the constructed polymer material sample into the LS-DYNA software;

[0112] The generation module 208 is used to generate a k file by performing finite element mesh generation on the geometric simulation model of the polymer material sample, and generating the k file according to the properties of the polymer material, the keywords of the defined UMAT subroutine, and the parameter assignment of the viscoelastic-hyperelastic constitutive mathematical model. The k file contains the calculation command file of each finite element information of the geometric simulation model. The finite element information includes at least the characteristic information of the finite elements, and the characteristics of the polymer material include the deformation characteristics of the polymer material.

[0113] The simulation module 210 is used to call the solver of the LS-DYNA software according to the keywords of the UMAT subroutine, calculate the k file, and obtain the simulation results of the dynamic mechanical behavior of the polymer material sample.

[0114] Specifically, the constructed viscoelastic constitutive mathematical model is programmed and embedded into the solver of the LS-DYNA software. The stress-strain relationship of the polymer material sample is calculated according to the defined k-file, thereby obtaining the simulation results, which are the viscoelastic mechanical response results of the polymer material under different force environments. It can be seen that the above-mentioned secondary development of LS-DYNA software can accurately predict the dynamic mechanical response of polymer materials that take into account both viscous and hyperelastic properties, thereby greatly improving the simulation accuracy of the LS-DYNA software.

[0115] In this embodiment, the construction module 202 is used to obtain the Maxwell model of the linear spring and the sticky pot in series and the Rivlin hyperelastic constitutive model of the strain energy function equation with power series N=2; based on the Maxwell model of the linear spring and the sticky pot in series and the Rivlin hyperelastic constitutive model of the strain energy function equation with power series N=2, the viscoelastic-hyperelastic constitutive mathematical model is constructed.

[0116] In this embodiment, the embedding module 204 is used to write the viscoelastic-hyperelastic constitutive mathematical model into the UMAT subroutine using FORTRAN language; open the dyna.f file in the lib file package of the LS-DYNA software on the Microsoft Visual C++ platform, and write the UMAT subroutine into the subbroutine umat41() program segment; compile the subbroutine umat41() program segment using the Intel(R) FortranCompiler compiler to obtain the lsdynavisco_hyper.exe executable solver embedded with the UMAT subroutine. Through the above method, the UMAT subroutine can be embedded into the LS-DYNA software to achieve the function of secondary development of the LS-DYNA software.

[0117] In this embodiment, the import module 206 is used to construct a geometric simulation model of the polymer material sample using model design software, based on the characteristic requirements of the polymer material; and to import the geometric simulation model of the polymer material sample into the preprocessing interface LS-PrePost of the LS-DYNA software.

[0118] In this embodiment, the generation module 208 is used to perform finite element mesh generation on the geometric simulation model of the polymer material sample to obtain multiple finite elements; define keywords for each finite element, which correspond to the UMAT subroutine; assign values ​​to the parameters in the viscoelastic-hyperelastic constitutive mathematical model; and generate the k-file based on the defined finite element keywords, the parameter values ​​of the viscoelastic-hyperelastic constitutive mathematical model, and the properties of the polymer material. By generating k-files, different polymer material samples can generate different k-files, or k-files with different parameters can be generated, thereby solving and calculating the simulation results through the aforementioned UMAT subroutine, resulting in higher simulation accuracy.

[0119] Simulation module 210 is used to compare the simulation results of the dynamic mechanical behavior of the polymer material sample with the stress-strain theoretical data of the same polymer material sample to obtain a comparison structure; based on the comparison results, the simulation results of the dynamic mechanical behavior of the polymer material sample are verified. This method effectively verifies the correctness, effectiveness, and reliability of the above approach.

[0120] Based on the same inventive concept, another embodiment of this specification provides a computer-readable storage medium storing one or more programs, which, when executed by an electronic device including multiple application programs, cause the electronic device to perform... Figure 1 The corresponding embodiment provides a simulation method for the dynamic mechanical behavior of materials based on LS-DYNA.

[0121] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on its differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0122] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0123] Those skilled in the art will understand that the embodiments of this specification can be provided as methods, systems, or computer program products. Therefore, this specification may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this specification may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0124] This specification is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this specification. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 The device that provides the function specified in each box.

[0125] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0126] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0127] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0128] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0129] The above description is merely an embodiment of this application and is not intended to limit this specification. Various modifications and variations can be made to this specification by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of the claims.

Claims

1. A simulation method for the dynamic mechanical behavior of materials based on LS-DYNA, characterized in that, include: Construct a constitutive mathematical model of viscoelasticity; The aforementioned viscoelastic constitutive mathematical model was written as a UMAT subroutine and embedded into the solver of the LS-DYNA software; Import the constructed geometric simulation model of the polymer material sample into LS-DYNA software; By performing finite element mesh generation on the geometric simulation model of the polymer material sample, and generating a k file based on the properties of the polymer material, the keywords of the defined UMAT subroutine, and the parameter assignment of the viscoelastic-hyperelastic constitutive mathematical model, the k file contains the calculation command file for each finite element information of the geometric simulation model. The finite element information includes at least the characteristic information of the finite elements, and the characteristics of the polymer material include the deformation characteristics of the polymer material. Based on the keywords of the UMAT subroutine, the solver of the LS-DYNA software is called to calculate the k-file and obtain the simulation results of the dynamic mechanical behavior of the polymer material sample.

2. The material dynamic mechanical behavior simulation method based on LS-DYNA according to claim 1, characterized in that, The properties of the polymer material include the loading conditions and boundary conditions of the polymer material. The loading conditions are the relationship between the force and deformation of the polymer material, and the boundary conditions are the force constraint conditions of the polymer material.

3. The material dynamic mechanical behavior simulation method based on LS-DYNA according to claim 1, characterized in that, The construction of the viscoelastic-hyperelastic constitutive mathematical model includes: Obtain the Maxwell model of a linear spring and a sticky pot in series and the Rivlin hyperelastic constitutive model of the power series N=2 of the strain energy function equation; Based on the Maxwell model of the linear spring and the sticky pot in series and the Rivlin hyperelastic constitutive model of the strain energy function equation with power series N=2, the viscous-hyperelastic constitutive mathematical model is constructed.

4. The material dynamic mechanical behavior simulation method based on LS-DYNA according to claim 3, characterized in that, The viscoelastic constitutive mathematical model is as follows: Where λ = 1 - ε is the tensile ratio in the direction of uniaxial compressive load; σ represents the material stress, and ε represents the material strain. C represents the strain rate, τ represents the time integral variable, and C represents the strain rate. 10 C 20 C 11 C 01 C 02 θ1 represents the Rivlin hyperelastic coefficient for a power series N=2, E1 represents the elastic coefficient for viscoelastic properties, and θ1 represents the viscosity coefficient for viscoelastic properties.

5. The material dynamic mechanical behavior simulation method based on LS-DYNA according to claim 1, characterized in that, The step of writing the viscoelastic-hyperelastic constitutive mathematical model into a UMAT subroutine and embedding it into the solver of the LS-DYNA software includes: The viscoelastic-hyperelastic constitutive mathematical model was written as the UMAT subroutine using the FORTRAN language; Open the dyna.f file in the lib folder of the LS-DYNA software on the C++ platform, and write the UMAT subroutine into the umat410 program segment; The subroutine umat41() program segment is compiled using the Intel(R) Fortran Compiler to obtain the lsdyna_visco_hyper.exe executable solver embedded with the UMAT subroutine.

6. The material dynamic mechanical behavior simulation method based on LS-DYNA according to claim 1, characterized in that, The process of importing the constructed geometric simulation model of the polymer material sample into the LS-DYNA software includes: Using model design software, a geometric simulation model of the polymer material sample is constructed based on the characteristics and requirements of the polymer material. The geometric simulation model of the polymer material sample is imported into the LS-DYNA software's preprocessing interface, LS-PrePost.

7. The material dynamic mechanical behavior simulation method based on LS-DYNA according to claim 1, characterized in that, The keywords for the UMAT subroutine include keywords for compressing rigid walls and compression speed, material keywords, calculation time keywords, and calculation step size keywords.

8. The material dynamic mechanical behavior simulation method based on LS-DYNA according to claim 7, characterized in that, The process involves generating a k-file by performing finite element mesh generation on the geometric simulation model of the polymer material sample, based on the properties of the polymer material, the defined keywords of the UMAT subroutine, and the parameter assignments of the viscoelastic-hyperelastic constitutive mathematical model. The k-file includes: Finite element meshing was performed on the geometric simulation model of the polymer material sample to obtain multiple finite element models; Define keywords for each finite element, and the keywords for each finite element correspond to the definitions of the UMAT subroutines; The parameters in the viscoelastic constitutive mathematical model are assigned values; The k-file is generated based on the defined keywords of the finite element method, the parameter assignments of the viscoelastic constitutive mathematical model, and the properties of the polymer material.

9. The material dynamic mechanical behavior simulation method based on LS-DYNA according to claim 1, characterized in that, After the UMAT subroutine's keywords are used to call the solver of the LS-DYNA software to calculate the k-file and obtain the simulation results of the dynamic mechanical behavior of the polymer material sample, the process includes: The simulation results of the dynamic mechanical behavior of the polymer material sample are compared with the stress-strain theoretical data of the same polymer material sample to obtain the comparison structure. Based on the comparison results, the simulation results of the dynamic mechanical behavior of the polymer material sample are verified.

10. A material dynamic mechanical behavior simulation system based on LS-DYNA, characterized in that, include: Modules are used to construct constitutive mathematical models of viscoelasticity; An embedded module is used to write the viscoelastic-hyperelastic constitutive mathematical model into a UMAT subroutine and embed it into the solver of the LS-DYNA software; The import module is used to import the geometric simulation model of the constructed polymer material sample into the LS-DYNA software; The generation module is used to perform finite element mesh generation on the geometric simulation model of the polymer material sample, and generate a k file based on the properties of the polymer material, the keywords of the defined UMAT subroutine, and the parameter assignment of the viscoelastic-hyperelastic constitutive mathematical model. The k file contains the calculation command file of each finite element information of the geometric simulation model. The finite element information includes at least the characteristic information of the finite elements, and the characteristics of the polymer material include the deformation characteristics of the polymer material. The simulation module is used to call the solver of the LS-DYNA software according to the keywords of the UMAT subroutine, calculate the k-file, and obtain the simulation results of the dynamic mechanical behavior of the polymer material sample.

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