Hybrid Natural Element Method for Elastic Large Deformation Problems

Elastic large deformation analysis based on the hybrid natural element method (HNEM) is presented in this paper. The natural neighbor interpolation is adopted to construct the shape functions for the HNEM. The incremental formulation of Hellinger-Reissner variational principle is used to derive discrete system of incremental equations under the total Lagrangian formulation. And the Newton-Raphson iteration is applied to solve these incremental equations. Compared with the natural element method (NEM), the HNEM can directly obtain nodal stresses of higher precision, which will bring advantage in the iteration process and improve computational efficiency in solving elastic large deformation problems. Some numerical examples demonstrate the validity of the HNEM for elastic large deformation problems.