APPLICATION OF ELEMENT-FREE GALERKIN METHOD IN ROTARY PIERCING PROCESS
A new numerical calculating method,element-free Galerkin method(EFGM),is employed to simulate a three-dimensional rotary piercing process.The element-free Galerkin method adopts Moving Least Squares(MLS) approximate shape functions,not meeting the Kronecker Delta function properties.The shape function is modified and converted to the interpolation function,so that the essential boundary condition can be directly imposed.Then,the calculating model for a rotary piercing process with the element-free Galerkin method is given,also the detailed derivation process is developed.The calculation results are obtained by the element-free Galerkin method with dual convergence criterions.The deformation of the piece is discussed.The variable field results by the element-free Galerkin method are compared with those by finite element methods,and the difference between them are explained.By the analysis and comparison,it is shown that the rotary piercing process calculated with the element-free Galerkin method is feasible and correct.