Research On Key Techniques Of Local Mesh Dynamic Refinement And Preprocessing In 2D Cutting Simulation Based On Abaqus

With the development of computer technology,numerical methods such as finite element methods are playing an increasingly important role in the fields of scientific research and engineering applications.The first task of the finite element method is to perform model discretization,that is,the generation of finite element meshes.As an approximate numerical simulation method,the degree of approximation of the analysis results and theoretical solutions depends on the number of elements,element shape,and node positions.For many factors,a reasonable grid can greatly improve the accuracy of the finite element calculation results.With the increase of the number of grid nodes,although the accuracy of the solution can be improved,it will also increase the calculation time and resources.In actual simulation,people only need to set in the area of interest,such as a region with a large stress gradient.A denser grid is sufficient.The local mesh dynamic refinement technology is to dynamically refine the mesh of the local area by filtering the mesh area,and finally can obtain relatively accurate results in a short time.Metal cutting is a very complex geometrically nonlinear and large deformation process with thermal and mechanical coupling.When the metal cutting process is simulated by finite element simulation,it is often the area near the tool tip that needs attention.Therefore,in this paper,the meshes near the tip of the blade are screened,and the meshes in the area are encrypted.At the same time,the physical field of the mesh between the thickness and thickness is transferred.The secondary development of the technology,while ensuring the accuracy of the simulation,significantly reduced the time required for the simulation.This article focuses on the following:(1)Aiming at how to apply the local mesh dynamic thinning technology in Abaqus,three key issues are proposed: the determination of the thinning area,the selection of the thinning mode and transition mode,and the transfer of the physics field.A corresponding solution was proposed,and the script programming of the mesh region filtering algorithm,the mesh refinement transition algorithm,and the physics field transfer algorithm was completed using Python language.(2)Based on the Abaqus simulation software and the above research results,the local mesh dynamic refinement technology was applied to the two-dimensional cutting simulation,and the orthogonal turning experiments of the titanium alloy Ti6Al4 V were carried out.The same cutting parameters were used under the same conditions.The accuracy of the finite element simulation model of the local mesh dynamic refinement technology was verified.At the same time,a quantitative comparative analysis of the calculation efficiency was performed on the finite element models with different mesh densities.Compared with the global mesh refinement method,the calculation efficiency Increased by 210%.(3)Based on the Plug-ins plug-in program in Abaqus,use Python to perform parametric modeling of 2D cutting simulation.By writing the kernel program and defining keywords,complete the fast 2D cutting model under different parameters.The modeling process,including the establishment of the tool workpiece geometric model and the division of the mesh,the determination of the workpiece material,and the setting of the cutting parameters,etc.,save the time consumed by the pre-processing in the finite element simulation.