Development Of Key Element Algorithm For Autonomous CAE Implicit Solver

As a typical representative of industrial software,CAE software is widely used in all aspects of manufacturing industry,and plays an important role in aerospace,automobile,ship,home appliances,consumer electronics,biomedical and many other fields.Based on the implicit statics solver development project of our research group,combined with the element theory and related algorithms,this paper mainly studies the key element algorithm development of the independent CAE implicit statics solver(1)Based on the calculation and development framework of implicit statics solver,the development framework of its internal computing unit is constructed,which improves the scalability and ease of use of the solver in cell development,and facilitates subsequent expansion and user use.(2)Based on the mechanical expression of plane stress and strain problems,the finite element solutions of plane stress and strain problems are studied.Combined with the interpolation functions of first-order triangle,first-order quadrilateral,secondorder triangle and second-order quadrilateral,eight kinds of plane stress and strain elements based on different interpolation functions are developed Some typical examples,such as slender straight beam and cook film,are used to test the performance of the developed element and verify the correctness of the element.(3)Based on the mechanical expression of three-dimensional stress problem,the finite element solution format of three-dimensional stress problem is studied.Combining the interpolation functions of first-order tetrahedron,first-order triangular prism,first-order hexahedron,second-order tetrahedron,second-order triangular prism and second-order hexahedron,six kinds of conventional three-dimensional stress elements based on different geometric configurations are developed;based on firstorder hexahedron element,combined with reduced product The hexahedral reduced integral element is developed by using the finite element method,and the hexahedral incompatible element is developed by combining the incompatible element theory.Based on the second-order tetrahedral element and the strain decomposition technique,the second-order tetrahedral modified format element is developed.The correctness of the element is verified by examples of three-dimensional cantilever slender straight beam and twisted beam.(4)Based on the central point based discrete shear gap(CP-DSG3)element algorithm of virtual center point,the triangular shell element is developed.The quadrilateral shell element is developed based on physical stabilization(QPH)element algorithm.The performance of the developed element in bending deformation,membrane deformation,shear deformation and other aspects is tested by classical plate and shell examples such as square plate,cylindrical shell,spherical shell,etc.,and the correctness of the developed element is verified.