Huan Wang¹, Weifeng Yuan^2,3, Fei Jia²

CMC-Computers, Materials & Continua, Vol.47, No.1, pp. 31-43, 2015, DOI:10.3970/cmc.2015.047.031

Abstract Compared with dealing with a linear system, solving a nonlinear system equation in numerical simulation requires generally more CPU time since iterative approach is usually used in the latter. To cut down the computing cost, a direct way is to reduce the degree of freedoms (DOF) of the problem under investigation. However, this kind of treatment may result in poorer accuracy. In this manuscript, a macro element method is proposed to improve computational efficiency in large-scaled nonlinear analysis. When this concept is incorporated into finite element analysis (FEA), all the members in the linear zones of a structure can be… More >

L. Dong¹, S. N. Atluri²

CMC-Computers, Materials & Continua, Vol.24, No.1, pp. 61-104, 2011, DOI:10.3970/cmc.2011.024.061

Abstract A simple procedure to formulate efficient and stable hybrid/mixed finite elements is developed, for applications in macro- as well as micromechanics. In this method, the strain and displacement field are independently assumed. Instead of using two-field variational principles to enforce both equilibrium and compatibility conditions in a variational sense, the independently assumed element strains are related to the strains derived from the independently assumed element displacements, at a finite number of collocation points within the element. The element stiffness matrix is therefore derived, by simply using the principle of minimum potential energy. Taking the four-node plane isoparametric element as an… More >

Yong Kou¹, Ke Jin¹, Xiaojing Zheng^1,2

CMC-Computers, Materials & Continua, Vol.22, No.2, pp. 129-146, 2011, DOI:10.3970/cmc.2011.022.129

Abstract Magnetic shielding needs to be employed to ensure proper operation of some electronic equipment which are sensitive to external magnetic interference, such as cryogenic valves located inside the ITER feeder cubicles. This paper is concerned with the shielding efficiency of the magnetic shielding enclosures. A 3-D theoretical model for Fe-Ni alloy magnetic shielding enclosures based on finite element method (FEM) is obtained with the nonlinear law of magnetization. The influence of shielding materials, enclosure configurations, single or multi- layer designs, and apertures on the shielding efficiency is investigated. It is shown that the proposed model can predict the shielding efficiency… More >

CMC-Computers, Materials & Continua, Vol.18, No.3, pp. 271-300, 2010, DOI:10.3970/cmc.2010.018.271

Abstract The processing maps are a superimposition of iso-efficiency contour map and flow instability map, which are used to design hot working processing conditions in a wide variety of materials. In order to construct the processing maps, the efficiency of power dissipation and an instability criterion taking into account the contribution of strain and microstructure evolution are proposed based on a set of microstructure-based viscoplastic constitutive equations. In viscoplastic constitutive equations, the grain size of matrix phase and the dislocation density are taken as internal state variables. And, the material constants in present equations can be identified by a genetic algorithm… More >