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 >

A.J. Shaw¹ and P.D. Gosling^1,2

CMC-Computers, Materials & Continua, Vol.18, No.3, pp. 237-270, 2010, DOI:10.3970/cmc.2010.018.237

Abstract This article has no abstract. More >

Metin Kök^1,2, Erdogan Kanca³

CMC-Computers, Materials & Continua, Vol.18, No.3, pp. 213-236, 2010, DOI:10.3970/cmc.2010.018.213

Abstract In this investigation, a new model was developed to predict the wear rate of Al2O3 particle-reinforced aluminum alloy composites by Genetic Expression Programming (GEP). The training and testing data sets were obtained from the well established abrasive wear test results. The volume fraction of particle, particle size of reinforcement, abrasive grain size and sliding distance were used as independent input variables, while wear rate (WR) as dependent output variable. Different models for wear rate were predicted on the basis of training data set using genetic programming and accuracy of the best model was proved with testing data set. The two-body… More >

Jun Xu^1,2, Yibing Li¹, Xi Chen^2,3, Yuan Yan^2,3, Dongyun Ge^4,1, Bohan Liu¹

CMC-Computers, Materials & Continua, Vol.18, No.2, pp. 183-212, 2010, DOI:10.3970/cmc.2010.018.183

Abstract The crack pattern in a PVB laminated windshield upon head impact is of considerable interest because it contains important information on energy mitigation, pedestrian protection, and accident reconstruction. We carry out a systematic numerical study based on the extended finite element method (XFEM), to investigate the effects of various material and system variables, including the impact speed, effective head mass, PVB interlayer material thickness and property, windshield curvature, aspect ratio and size, boundary constraint, impact angle and off-center impact, on the parameters characterizing the resulting crack pattern, i.e. the crack length, crack angle and circumferential crack shape. General relations bridging… More >

Hui- Shen^1,2, Zheng Hong Zhu³

CMC-Computers, Materials & Continua, Vol.18, No.2, pp. 155-182, 2010, DOI:10.3970/cmc.2010.018.155

Abstract This paper investigates the buckling and postbuckling of simply supported, nanocomposite plates with functionally graded nanotube reinforcements subjected to uniaxial compression in thermal environments. The nanocomposite plates are assumed to be functionally graded in the thickness direction using single-walled carbon nanotubes (SWCNTs) serving as reinforcements and the plates' effective material properties are estimated through a micromechanical model. The higher order shear deformation plate theory with a von Kármán-type of kinematic nonlinearity is used to model the composite plates and a two-step perturbation technique is performed to determine the buckling loads and postbuckling equilibrium paths. Numerical results for perfect and imperfect,… More >

A.Z. Lorbiecka¹, B. Šarler^1,2

CMC-Computers, Materials & Continua, Vol.18, No.1, pp. 69-104, 2010, DOI:10.3970/cmc.2010.018.069

Abstract The aim of this paper is simulation of thermally induced liquid-solid dendritic growth in two dimensions by a coupled deterministic continuum mechanics heat transfer model and a stochastic localized phase change kinetics model that takes into account the undercooling, curvature, kinetic and thermodynamic anisotropy. The stochastic model receives temperature information from the deterministic model and the deterministic model receives the solid fraction information from the stochastic model. The heat transfer model is solved on a regular grid by the standard explicit Finite Difference Method (FDM). The phase-change kinetics model is solved by the classical Cellular Automata (CA) approach and a… More >

C.Y. Lin¹, M.H. Gu¹, D.L. Young^1,2

CMC-Computers, Materials & Continua, Vol.18, No.1, pp. 43-68, 2010, DOI:10.3970/cmc.2010.018.043

Abstract The telegraph equations are solved by using the meshless numerical method called the time-marching method of fundamental solutions (TMMFS) in this paper. The present method is based on the method of fundamental solutions, the method of particular solutions and the Houbolt finite difference scheme. The TMMFS is a meshless numerical method, and has the advantages of no mesh building and numerical quadrature. Therefore in this study we eventually solved the multi-dimensional telegraph equation problems in irregular domain. There are totally six numerical examples demonstrated, in order they are one-dimensional telegraph equation, one-dimensional non-decaying telegraph problem, two-dimensional telegraph equation in irregular… More >

C. Jiang¹, Y.C. Bai¹, X. Han^1,2, H.M. Ning¹

CMC-Computers, Materials & Continua, Vol.18, No.1, pp. 21-42, 2010, DOI:10.3970/cmc.2010.018.021

Abstract In this paper, an efficient interval optimization method based on a reliability-based possibility degree of interval (RPDI) is suggested for the design of uncertain structures. A general nonlinear interval optimization problem is studied in which the objective function and constraints are both nonlinear and uncertain. Through an interval order relation and a reliability-based possibility degree of interval, the uncertain optimization problem is transformed into a deterministic one. A sequence of approximate optimization problems are constructed based on the linear approximation technique. Each approximate optimization problem can be changed to a traditional linear programming problem, which can be easily solved by… More >

Chein-Shan Liu¹

CMC-Computers, Materials & Continua, Vol.18, No.1, pp. 1-20, 2010, DOI:10.3970/cmc.2010.018.001

Abstract We are concerned with the reconstruction of an unknown space-dependent rigidity coefficient in a wave equation. This problem is known as one of the inverse scattering problems. Based on a two-point Lie-group equation we develop a Lie-group adaptive method (LGAM) to solve this inverse scattering problem through iterations, which possesses a special character that by using onlytwo boundary conditions and two initial conditions, as those used in the direct problem, we can effectively reconstruct the unknown rigidity function by aself-adaption between the local in time differential governing equation and the global in time algebraic Lie-group equation. The accuracy and efficiency… More >

Weichung Yeih¹, Chein-Shan Liu², Chung-Lun Kuo³, Satya N. Atluri⁴

CMC-Computers, Materials & Continua, Vol.17, No.3, pp. 275-302, 2010, DOI:10.3970/cmc.2010.017.275

Abstract In this paper, a multiple-source-point boundary-collocation Trefftz method, with characteristic lengths being introduced in the basis functions, is proposed to solve the direct, as well as inverse Cauchy problems of the Laplace equation for a multiply connected domain. When a multiply connected domain with genus p (p>1) is considered, the conventional Trefftz method (T-Trefftz method) will fail since it allows only one source point, but the representation of solution using only one source point is impossible. We propose to relax this constraint by allowing many source points in the formulation. To set up a complete set of basis functions, we… More >