Research On Finite Element Automatic Modeling Technology Of Radial Tire Tread Pattern

With the rapid development of China's automobile and tire industry,radial tires have become the leading products in the tire market with their excellent performance.However,the radial tire tread pattern has a complicated geometric structure,and the finite element modeling process is very difficult.The traditional method is to first establish a three-dimensional geometric shape through the two-dimensional structural design of the pattern,and then import it into the finite element preprocessing software for manual meshing.The process requires a lot of time and effort.This paper studies the technology of generating three-dimensional mesh models based on finite element nodes,and develops and designs an automatic modeling program for tire patterns.It realizes the direct generation of three-dimensional meshes from two-dimensional structural design drawings of patterns,avoiding the tedious construction of three-dimensional geometric shapes.The steps greatly improve the modeling efficiency,and at the same time ensure the high-quality characteristics of the grid cells,laying the foundation for the establishment of a tire automation simulation system.This paper first summarizes the typical hexahedral meshing method,and explores the possibility of applying its algorithmic ideas to tire pattern modeling.Then,based on the two difficult points of three-dimensional geometric modeling and meshing in the tire pattern modeling process,combined with the actual tire design and production process,a method for creating a tread pattern model based on finite element nodes was proposed,and the overall modeling process was planned.Visual LISP was used to carry out the secondary development of AutoCAD to assist in realizing the two-dimensional grid division of the pattern structure diagram.In HyperMesh,based on the parameters such as the groove depth of the pattern,the extraction of the grid cells and node information of the pattern structure graph is completed.Use MATLAB to compile a program to classify the extracted grid information and store it in an EXCEL table to prepare for the subsequent automatic modeling program calls.A pattern automatic modeling program was developed based on MATLAB,which mainly includes two modules:3D node coordinate acquisition and grid unit connection.First,map the grid pattern of the pattern development map to the actual surface mesh model,generate all nodes by projecting the normal direction of the actual surface,and then use the node numbering method on the actual surface mesh model for each layer of the auxiliary surface.The units are classified and connected based on the right-hand rule to generate a three-dimensional grid model of the pattern.Finally,the program is expanded and a GUI parameterized interface is developed to achieve the universality of the program.Taking the 205/55R16 semi-steel radial tire as the reference tire,a tire body part model is created and combined with the tread pattern model generated by the automatic modeling program described above to form a complete tread tire model.In the ABAQUS,the inflation and static load simulation analysis of the tread tire model was carried out.Under the inflation condition,the tire crown and sidewall were significantly deformed,and the shoulder and bead were basically unchanged.The MISES stress is symmetrical about the midface of the tire,and the skeleton material bears most of the stress of the tire.The axial force of the belt steel cord along the tire circumferential direction is evenly distributed.Under static load conditions,the grounding end of the tire is significantly deformed,and the axial force of the belt cord is antisymmetrically distributed about the 180°meridian plane and the midplane of the tire.The shape of the ground contact mark has undergone an elliptical to rectangular-like change.The stress is dispersed from the center of the tread to the shoulder area,and the phenomenon of "warpage" occurs.When the tire establishes stable contact with the ground,there is an approximately linear relationship between the amount of vertical load applied and the amount of tire sinking.Both simulation results are consistent with the actual situation,illustrating the effectiveness of the automatic tread pattern modeling technology.