Z. Xu¹, L. G. Zhou¹, Jian Wang¹, Timothy S. Cale², Hanchen Huang^1,3

CMC-Computers, Materials & Continua, Vol.3, No.1, pp. 43-48, 2006, DOI:10.3970/cmc.2007.003.043

Abstract Recent studies show that three-dimensional Ehrlich-Schwoebel (3D ES), or facet-facet, barriers of face-centered-cubic metals are substantially higher than other surface diffusion barriers. This paper presents the numerical results of 3D ES barriers for body-centered-cubic W, using classical molecular statics calculations and the nudged elastic band method. Results show that an adatom on W{110} has a diffusion barrier of 0.49 eV on the flat surface, 0.66 eV over a monolayer step, and 0.98 eV over a ridge to a neighboring {100} facet, which is one 3D ES barrier. More >

K.Y. Volokh ¹

CMC-Computers, Materials & Continua, Vol.3, No.1, pp. 37-42, 2006, DOI:10.3970/cmc.2007.003.037

Abstract Lagrangian or referential equilibrium equations for materials undergoing large deformations are of interest in the developing fields of mechanics of soft biomaterials and nanomechanics. The main feature of these equations is the necessity to deal with the First Piola-Kirchhoff, or nominal, stress tensor which is a two-point tensor referring simultaneously to the reference and current configurations. This two-point nature of the First Piola-Kirchhoff tensor is not always appreciated by the researchers and the total covariant derivative necessary for the formulation of the equilibrium equations in curvilinear coordinates is sometimes inaccurately confused with the regular covariant derivative. Surprisingly, the traditional continuum… More >

Lingfei Gao¹, Xiaoping Zheng^1,2, Zhenhan Yao¹

CMC-Computers, Materials & Continua, Vol.3, No.1, pp. 25-36, 2006, DOI:10.3970/cmc.2007.003.025

Abstract A general numerical approach is developed to model the elastic behaviours and failure processes of heterogeneous materials. The heterogeneous material body is assumed composed of a large number of convex polygon lattices with different phases. These phases are locally isotropic and elastic-brittle with the different lattices displaying variable material parameters and a Weibull-type statistical distribution. When the effective strain exceeds a local fracture criterion, the full lattice exhibits failure uniformly, and this is modelled by assuming a very small Young modulus value. An auto-select loading method is employed to model the failure process. The proposed hybrid approach is applied to… More >

I. Smojver¹, J. Sorić²

CMC-Computers, Materials & Continua, Vol.3, No.1, pp. 13-24, 2006, DOI:10.3970/cmc.2007.003.013

Abstract The paper addresses the problem of impact on layered fibre composites. The behaviour of composite laminates under impact loading is dependent not only on the velocity but also on the mass and geometry of the impactor. Using micromechanical Mori-Tanaka approach, mechanical properties of the laminate have been calculated utilizing the material constants of the fibre and matrix. General purpose FEM software ABAQUS has been modified by means of user written subroutines for modelling of composite laminate and rigid impactor. The kinematics of the impact has been simulated using transient dynamic analysis. Employing user defined multi point constraints, delamination zones have… More >

Aimin Jiang^1,2, Haojiang Ding²

CMC-Computers, Materials & Continua, Vol.3, No.1, pp. 1-12, 2006, DOI:10.3970/cmc.2007.003.001

Abstract This paper presents a development of the boundary contour method (BCM) for magneto-electro-elastic media. Firstly, the divergence-free of the integrand of the magneto- electro-elastic boundary element is proved. Secondly, the boundary contour method formulations are obtained by introducing linear shape functions and Green's functions (Computers & Structures, 82(2004):1599-1607) for magneto-electro-elastic media and using the rigid body motion solution to regularize the BCM and avoid computation of the corner tensor. The BCM is applied to the problem of magneto-electro-elastic media. Finally, numerical solutions for illustrative examples are compared with exact ones and those of the conventional boundary element method (BEM). The… More >

Eduardo Divo¹, Alain J. Kassab²

CMC-Computers, Materials & Continua, Vol.2, No.4, pp. 277-288, 2005, DOI:10.3970/cmc.2005.002.277

Abstract A Dual Reciprocity Boundary Element Method is formulated to solve non-linear heat conduction problems. The approach is based on using the Kirchhoff transform along with lagging of the effective non-linear thermal diffusivity. A posteriori error estimate is used to provide effective estimates of the temporal and spatial error. A numerical example is used to demonstrate the approach. More >

D.L. Young^1,3, C.S. Chen², T.K. Wong³

CMC-Computers, Materials & Continua, Vol.2, No.4, pp. 267-276, 2005, DOI:10.3970/cmc.2005.002.267

Abstract A meshless time domain numerical method based on the radial basis functions using multiquadrics (MQ) is employed to simulate electromagnetic field problems by directly solving the time-varying Maxwell's equations without transforming to simplified versions of the wave or Helmholtz equations. In contrast to the conventional numerical schemes used in the computational electromagnetism such as FDTD, FETD or BEM, the MQ method is a truly meshless method such that no mesh generation is required. It is also easy to deal with the appropriate partial derivatives, divergences, curls, gradients, or integrals like semi-analytic solutions. For illustration purposes, the MQ method is employed… More >

Carlos J. S. Alves, Pedro R. S. Antunes¹

CMC-Computers, Materials & Continua, Vol.2, No.4, pp. 251-266, 2005, DOI:10.3970/cmc.2005.002.251

Abstract In this work we show the application of the Method of Fundamental Solutions(MFS) in the determination of eigenfrequencies and eigenmodes associated to wave scattering problems. This meshless method was already applied to simple geometry domains with Dirichlet boundary conditions (cf. Karageorghis (2001)) and to multiply connected domains (cf. Chen, Chang, Chen, and Chen (2005)). Here we show that a particular choice of point-sourcescan lead to very good results for a fairly general type of domains. Simulations with Neumann boundary conditionare also considered. More >

A. La Rocca¹, H. Power¹, V. La Rocca², M. Morale²

CMC-Computers, Materials & Continua, Vol.2, No.4, pp. 239-250, 2005, DOI:10.3970/cmc.2005.002.239

Abstract This work presents a meshless numerical scheme for the solution of time dependent non linear heat transfer problems in terms of a radial basis function Hermite collocation approach. The proposed scheme is applied to foodstuff's samples during freezing process; evaluation of the time evolution of the temperature profile along the sample, as well as at the core, is carried out. The moving phase-change zone is identified in the domain and plotted at several timesteps. The robustness of the proposed scheme is tested by a comparison of the obtained numerical results with those found using a Finite Volume Method and with… More >

G. Mishuris¹, A. Öchsner², G. Kuhn³

CMC-Computers, Materials & Continua, Vol.2, No.4, pp. 227-238, 2005, DOI:10.3970/cmc.2005.002.227

Abstract FEM-evaluation of imperfect transmission conditions has been performed for a modelling problem of an elastic structure with a thin intermediate interface. Very good correlations with theoretical results have been obtained. Additionally, the possible error connected with introducing the transmission conditions instead of the intermediate zone has been estimated depending on mechanical properties of the zone. More >