Open Access
ARTICLE
Yaoming Zhang1, Yan Gu1, Jeng-Tzong Chen2
CMES-Computer Modeling in Engineering & Sciences, Vol.50, No.1, pp. 1-20, 2009, DOI:10.3970/cmes.2009.050.001
Abstract There exist nearly singular integrals for thin walled structures in the boundary element method (BEM). In this paper, an efficient analytical method is developed to deal with the nearly singular integrals in the boundary integral equations (BIEs) for 2-D thin walled structures. The developed method is possible for problems defined in high-order geometry elements when the nearly singular integrals need to be calculated. For the analysis of nearly singular integrals with high-order geometry elements, much fewer boundary elements can be used to achieve higher accuracy. More importantly, computational models of thin walled structures or thin shapes in structures demand a… More >
Open Access
ARTICLE
Z.H.Yao1
CMES-Computer Modeling in Engineering & Sciences, Vol.50, No.1, pp. 21-46, 2009, DOI:10.3970/cmes.2009.050.021
Abstract The traditional time domain boundary integral equation (TDBIE) of elastodynamics is formulated based on the time dependent fundamental solution and the reciprocal theorem of elastodynamics. The time dependent fundamental solution of the elastodynamics is the response of the infinite elastic medium under a unit concentrate impulsive force subjected at a point and at an instant, including not only the pressure wave and shear wave, but also the Laplace wave with speed between that of P and S waves. In this paper, a new TDBIE is derived directly from the initial boundary value problem of the partial differential equation of elastodynamics,… More >
Open Access
ARTICLE
Tai-Ming Chang1, Chien-Chou Weng1, Mei-Jiau Huang1,2, Chun-KaiLiu2, Chih-Kuang Yu2
CMES-Computer Modeling in Engineering & Sciences, Vol.50, No.1, pp. 47-66, 2009, DOI:10.3970/cmes.2009.050.047
Abstract We employ the non-equilibrium molecular dynamics (NEMD) simulation to calculate the in-plane thermal conductivity of silicon thin films of thickness 2.2nm and 11nm. To eliminate the finite-size effect, samples of various lengths are simulated and an extrapolation technique is applied. To perform the quantum correction which is necessary as the MD simulation temperature is lower than Debye temperature, the confined phonon spectra are obtained in advance via the EMD simulations. The investigation shows the thermal conductivities corrected based on the bulk and thin-film phonon densities of states are very close and they agree excellently with the theoretical predictions of a… More >
Open Access
ARTICLE
Sudib K. Mishra1, J. K. Paik2, S. N. Atluri1
CMES-Computer Modeling in Engineering & Sciences, Vol.50, No.1, pp. 67-96, 2009, DOI:10.3970/cmes.2009.050.067
Abstract We present a simulation based study, by combining several models involving multiple time scales and physical processes, which govern the interfacial stress corrosion cracking (SCC) in grain boundaries, layered composites or bi-materials, and the mechanisms of inhibition using `smart' agents. The inhibiting agents described herein, automatically sense the initiation of damage, migrate to the sites and delay the corrosion kinetics involved in the process. The phenomenon of SCC is simulated using the lattice spring model (for the mechanical stresses), coupled with a finite difference model of diffusing species, causing the dissolution of the interfacial bonds. The dissolution is expressed through… More >