Open Access
ARTICLE
Ch,ra S. Yerramalli1, Anthony M. Waas2
CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 1-16, 2004, DOI:10.3970/cmes.2004.006.001
Abstract Results from a 3D finite element based study of the compression response of unidirectional fiber reinforced polymer matrix composites (FRPC) are presented in this paper. The micromechanics based study was used to simulate the compressive response of glass and carbon fiber reinforced polymer matrix composites, with a view to understanding the effect of fiber diameter on compression strength. Results from the modeling and simulation indicate the presence of a complex three dimensional stress state in the matrix of the FRPC. Results from the simulation highlight the role of fiber diameter on the compressive response of FRPC. In particular, it is… More >
Open Access
ARTICLE
J. H. Jackson1, A. S. Kobayashi2, S. N. Atluri3
CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 17-30, 2004, DOI:10.3970/cmes.2004.006.017
Abstract The Tε* integral was calculated numerically along an extending, tunneling crack front in an 8 mm thick, aluminum three-point bend (3PB) specimen, using a numerical model driven by experimentally obtained surface displacements. The model provided input to a contour integration for the Tε* integral, via the Equivalent Domain Integral (EDI) method with incremental plasticity. Validity of the analysis was ensured by the agreement of the Tε* integral obtained on the surface (plane stress) and the plane stress values from previous studies. Tε*
was observed to decrease from the outer surface of the specimen to the… More >
Open Access
ARTICLE
W. J. Mansur1, A. I. Abreu1, J. A. M. Carrer1
CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 31-42, 2004, DOI:10.3970/cmes.2004.006.031
Abstract This work is concerned with the computation of the contribution of initial conditions in two-dimensional (2D) frequency-domain analysis of transient scalar wave propagation problems with the corresponding Boundary Element Method (BEM) formulation. The paper describes how pseudo-forces, represented by generalized functions, can replace the initial conditions, related to the potential and its time derivative. The generation of such pseudo-forces is the subject of a detailed discussion. The formulation presented here carries out Discrete Fourier Transform (Direct: DFT, and Inverse: IDFT) via FFT (Fast Fourier Transform) algorithms. At the end of the paper four examples are presented in order to show… More >
Open Access
ARTICLE
António Tadeu1, Julieta António and Nuno Simões
CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 43-58, 2004, DOI:10.3970/cmes.2004.006.043
Abstract This Analytical Green's functions for the steady-state response of homogeneous three-dimensional unbounded, half-space, slab and layered solid media subjected to a spatially sinusoidal harmonic heat line source are presented. In the literature, this problem is frequently referred to as the two-and-a-half dimensional fundamental solution or 2.5D Green's functions.
The proposed equations are theoretically interesting in themselves and they are also useful as benchmark results for validating numerical applications. They are also of great practical use in the formulation of three dimensional heat transfer problems in layered solid formations using integral transform methods and/or boundary elements.
The final expressions… More >
Open Access
ARTICLE
N. Mai-Duy1, T. Tran-Cong2
CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 59-76, 2004, DOI:10.3970/cmes.2004.006.059
Abstract This paper presents a new domain decomposition technique based on the use of Boundary Integral Equations (BIEs) for the analysis of viscous flow problems. The domain of interest is divided into a number of non-overlapping subdomains and an iterative procedure is then employed to update the boundary conditions at interfaces. The new feature in the present work is that at each iteration, the relevant two subdomains, together containing a particular interface, are assumed to satisfy the governing BI equations which they do at the end of a convergent iterative process. Hence the boundary conditions on such an interface can be… More >
Open Access
ARTICLE
E. Pan1, X. Jiang1
CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 77-90, 2004, DOI:10.3970/cmes.2004.006.077
Abstract It is of great importance to understand the factors that contribute to the strain and electrical distributions, which are induced by the misfit strain between a buried quantum wire (QWR) and its surrounding matrix. One of the important factors is the shape or geometry of cross section of the QWR. Utilizing a recent exact closed-form solution [Pan (2004)], we study the model system of QWRs with different shapes and calculate both the surface and internal elastic and piezoelectric fields induced by QWRs embedded in semiconductor GaAs substrates by properly setting the size and location of the QWRs. The effects of… More >
Open Access
ARTICLE
Shengping Shen1, S. N. Atluri1
CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 91-104, 2004, DOI:10.3970/cmes.2004.006.091
Abstract An atomistic level stress tensor is defined with physical clarity, based on the SPH method. This stress tensor rigorously satisfies the conservation of linear momentum, and is appropriate for both homogeneous and inhomogeneous deformations. The formulation is easier to implement than other stress tensors that have been widely used in atomistic analysis, and is validated by numerical examples. The present formulation is very robust and accurate, and will play an important role in the multiscale simulation, and in molecular dynamics. An equivalent continuum is also defined for the molecular dynamics system, based on the developed definition of atomistic stress and… More >
Open Access
ARTICLE
Haiyi Liang1, C.H. Woo1,2, Hanchen Huang3, A.H.W. Ngan4, T.X. Yu5
CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 105-114, 2004, DOI:10.3970/cmes.2004.006.105
Abstract Molecular dynamics (MD) simulations are performed to study crystalline plasticity during nano-indentation by comparing the elastic-plastic response of three copper substrates with surfaces (001), (110), and (111) crystallographic planes. The effects of elastic anisotropy and crystallographic symmetry on the reduced modulus, dislocation nucleation, and subsequent microstructure evolution, are investigated. The reduced modulus of (111) surface is found to be the largest, while that of (001) surface is the smallest. Elastic stress distribution calculated from finite element method (FEM) is qualitatively consistent with the MD simulation results. Significant differences exist in the deformation behavior in the three different crystallographic orientations. The… More >
Open Access
CORRECTION
Z.Y. Qian1, Z.D. Han1, S.N. Atluri1
CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 115-122, 2004, DOI:10.3970/cmes.2004.006.115
Abstract This article has no abstract. More >