STORAGE METHOD OF FE EQUATIONS AND ITS APPLICATION IN NUMERICAL SIMULATION OF SHEET METAL FORMING

A finite element equation always is a linear large sparse matrix equation and solving finite element equations is a key process in the numerical simulation of sheet metal forming. The solving method of equations and storage technology of the stiffness matrix affect the calculate efficiency of FEM numerical analysis significantly. In order to improve the solving efficiency of the self-developed code Quick-Form, the direct solver is replaced by the iterative solver. Based on two definitions of general adjacent node and general nodal adjacent relation, the generation principle of the total stiffness matrix and the distribution rules about nonzero matrix are introduced. An improved compact storage scheme named one dimension array with variational band width is proposed for the iterative algorithm solver, which can save large physical memory and avoid the optimization of nodal numbering. Numerical example demonstrates the higher efficiency and less memory needed of this proposed algorithm.