J. Sladek¹, V. Sladek¹, P. Stanak¹, Ch. Zhang², M. Wünsche²

CMC-Computers, Materials & Continua, Vol.23, No.1, pp. 35-68, 2011, DOI:10.3970/cmc.2011.023.035

Abstract A contour integral method is developed for the computation of stress intensity, electric and magnetic intensity factors for cracks in continuously nonhomogeneous magnetoelectroelastic solids under a transient dynamic load. It is shown that the asymptotic fields in the crack-tip vicinity in a continuously nonhomogeneos medium are the same as in a homogeneous one. A meshless method based on the local Petrov-Galerkin approach is applied for the computation of the physical fields occurring in the contour integral expressions of intensity factors. A unit step function is used as the test functions in the local weak-form. This More >

Yihua Xiao¹, Xu Han^1,2, Dean Hu¹

CMC-Computers, Materials & Continua, Vol.23, No.1, pp. 9-34, 2011, DOI:10.3970/cmc.2011.023.009

Abstract For impact computations, it is efficient to model small and large deformation regions by Finite Element Method (FEM) and Smoothed Particle Hydrodynamics (SPH), respectively. However, it requires an effective algorithm to couple FEM and SPH calculations. To fulfill this requirement, an alternative coupling algorithm is presented in this paper. In the algorithm, the coupling between element and particle regions are achieved by treating elements as imaginary particles and applying equivalent tractions to element sides on coupling interfaces. In addition, an adaptive coupling technique is proposed based on the algorithm to improve the computational efficiency of More >

Xiaozhi Tang¹, Yafang Guo¹, Yu Gao¹

CMC-Computers, Materials & Continua, Vol.23, No.1, pp. 1-8, 2011, DOI:10.3970/cmc.2011.023.001

Abstract Atomistic simulations were performed to study the nanoindentation for two kinds of FCC metals, aluminum and copper. Due to the higher stacking faults in aluminum than in copper, two different deformation mechanisms were observed in our simulation under exactly the same simulation condition. Aluminum and copper also showed different mechanical properties in the unloading stage. The influence of stacking sequence along the loading direction on deformation mechanism was also investigated in this paper. More >

J.M. Zhu¹, X.C. Wang¹, D. Wei², Y.H. Liu², B.Y. Xu²

CMC-Computers, Materials & Continua, Vol.22, No.3, pp. 261-274, 2011, DOI:10.3970/cmc.2011.022.261

Abstract The residual stiffness of concrete member after fire is a very important parameter of the load-bearing ability and seismic performance of fire-damaged concrete structures. It is also one of the most important criteria for repairing and reinforcing the fire-damaged concrete structures. Based on the equivalent elastic modulus method, improved segment model method and parameter inversion method developed in this paper, the residual stiffness of concrete members exposed to standard fire is calculated and the effects of fire duration, steel ratio and section size on the stiffness are also presented in detail. The results show that More >

H. T. Chen¹,K. H. Hsu¹, S. K. Lee¹, L. Y. Haung¹

CMC-Computers, Materials & Continua, Vol.22, No.3, pp. 239-260, 2011, DOI:10.3970/cmc.2011.022.239

Abstract The inverse scheme of the finite difference method in conjunction with the least-squares scheme and experimental measured temperatures is proposed to solve a two-dimensional steady-state inverse heat conduction problem in order to estimate the natural-convection heat transfer coefficient under the isothermal situation [`h] iso from three vertical fins mounted on a vertical plate and fin efficiency hf for various values of the fin spacing and fin height. The measured fin temperatures and ambient air temperature are measured from the present experimental apparatus conducted in a small wind tunnel. The heat transfer coefficient on the middle More >

E. Lescoute¹, T. De Rességuier¹, J.-M. Chevalier², J. Breil³, P.-H. Maire², G. Schurtz³

CMC-Computers, Materials & Continua, Vol.22, No.3, pp. 219-238, 2011, DOI:10.3970/cmc.2011.022.219

Abstract With the ongoing development of high energy laser facilities designed to achieve inertial confinement fusion, the ability to simulate debris ejection from metallic shells subjected to intense laser irradiation has become a key issue. We present an experimental and numerical study of fragmentation processes generating high velocity ejecta from laser shock-loaded metallic targets (aluminium and gold). Optical transverse shadowgraphy is used to observe and analyze dynamic fragmentation and debris ejection. Experimental results are compared to computations involving a fragmentation model based on a probabilistic description of material tensile strength. A correct overall consistency is obtained. More >

Chia-Cheng Tsai ¹

CMC-Computers, Materials & Continua, Vol.22, No.3, pp. 197-218, 2011, DOI:10.3970/cmc.2011.022.197

Abstract This paper describes the combination of the method of fundamental solutions (MFS) and the dual reciprocity method (DRM) as a meshless numerical method to solve problems of Kirchhoff plates under arbitrary loadings. In the solution procedure, a arbitrary distributed loading is first approximated by either the multiquadrics (MQ) or the augmented polyharmonic splines (APS), which are constructed by splines and monomials. The particular solutions of multiquadrics, splines and monomials are all derived analytically and explicitly. Then, the complementary solutions are solved formally by the MFS. Furthermore, the boundary conditions of lateral displacement, slope, normal moment,… More >

Gregor Kosec¹, Miha Založnik², Božidar Šarler¹, Hervé Combeau²

CMC-Computers, Materials & Continua, Vol.22, No.2, pp. 169-196, 2011, DOI:10.3970/cmc.2011.022.169

Abstract The simulation of macrosegregation as a consequence of solidification of a binary Al-4.5%Cu alloy in a 2-dimensional rectangular enclosure is tackled in the present paper. Coupled volume-averaged governing equations for mass, energy, momentum and species transfer are considered. The phase properties are resolved from the Lever solidification rule, the mushy zone is modeled by the Darcy law and the liquid phase is assumed to behave like an incompressible Newtonian fluid. Double diffusive effects in the melt are modeled by the thermal and solutal Boussinesq hypothesis. The physical model is solved by the novel Local Radial… More >

P. Zhao¹, G. Shi^1,2

CMC-Computers, Materials & Continua, Vol.22, No.2, pp. 147-168, 2011, DOI:10.3970/cmc.2011.022.147

Abstract The Poisson ratio is a very important mechanical parameter for both single-walled carbon nanotubes (SWCNTs) and graphene. But, the Poisson ratios of SWCNTs and graphene can not be determined by the direct measurement on the nanoscale specimen, and Poisson ratios of SWCNTs and graphene predicted by different models vary in a huge range. An improved molecular structural mechanics model, where the bond angle variations are modeled by the flexible connections of framed structures, is employed in this paper to predict the Poisson ratios of SWCNTs and monolayer graphene sheets. The present results indicate that the… 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 More >