Application of 2D base force element method with complementary energy principle for arbitrary meshes

作者：Peng Yijiang^*; Zong Nana; Zhang Lijuan; Pu Jiwei

来源：Engineering Computations, 2014, 31(4): 691-708.

DOI：10.1108/EC-10-2011-0125

• Finite element method
• Elasticity
• Arbitrary mesh
• Base force element method
• Base forces
• Complementary energy

Purpose - The purpose of this paper is to present a two-dimensional (2D) model of the base force element method (BFEM) based on the complementary energy principle. The study proposes a model of the BFEM for arbitrary mesh problems.
Design/methodology/approach - The BFEM uses the base forces given by Gao (2003) as fundamental variables to describe the stress state of an elastic system. An explicit expression of element compliance matrix is derived using the concept of base forces. The detailed formulations of governing equations for the BFEM are given using the Lagrange multiplier method. The explicit displacement expression of nodes is given. To verify the 2D model, a program on the BFEM using MATLAB language is made and a number of examples on arbitrary polygonal meshes and aberrant meshes are provided to illustrate the BFEM.
Findings - A good agreement is obtained between the numerical and theoretical results. Based on the studies, it is found that the 2D formulation of BFEM with complementary energy principle provides reliable predictions for arbitrary mesh problems.
Research limitations/implications - Due to the use of Lagrange multiplier method, there are more basic unknowns in the control equation. The proposed method will be improved in the future.
Practical implications - This paper presents a new idea and a new numerical method, and to explore new ways to solve the problem of arbitrary meshes.
Originality/value - The paper presents a 2D model of the BFEM using the complementary energy principle for arbitrary mesh problems.

• 出版日期2014
• 单位北京工业大学