Linjun Wang^1,2, Xu Han³, Youxiang Xie⁴

CMC-Computers, Materials & Continua, Vol.31, No.2, pp. 113-126, 2012, DOI:10.3970/cmc.2012.031.113

Abstract In this paper, a new iterative regularization method (ITR) is presented to solve the reconstruction of multi-source dynamic loads acting on the structure of simple supported plate. Based on a quadratical convergence method, this method is used to compute the the approximate inverse of square matrix. The theoretical proofs and numerical test show that the proposed method is very effective. Finally, the present method is applied to the identification of the multi-source dynamic loads on a surface of simply supported plate. Numerical simulations of two examples demonstrate the effectiveness and robustness of the present method. More >

Chien-Ching Ma^1,2, Yi-Hsien Lin², Shih-Hao Lin²

CMC-Computers, Materials & Continua, Vol.31, No.1, pp. 37-64, 2012, DOI:10.3970/cmc.2012.031.037

Abstract In this article, the transient response in a functionally graded material (FGM) slab is analyzed by Laplace transform technique. The numerical Laplace inversion (Durbin's formula) is used to calculate the dynamic behavior of the FGM slab. The slab is subjected an uniform loading at the upper surface, and the lower surface are assumed to be traction-free or fixed conditions. The analytical solutions are presented in the transform domain and the numerical Laplace inversion is performed to obtain the transient response in time domain. To take the accuracy and computational efficiency in consideration, Durbin's method is suitable for calculating the long-time… More >

Zhanqi Cheng¹, Zhenyu Wang¹, Zhongtao Luo^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.3, pp. 509-527, 2019, DOI:10.31614/cmes.2019.04339

Abstract In this work, a bond-based peridynamics (PD) model was built to analyze the dynamic fracture of shale material. Both the the convergence studies and the result of dynamic crack propagation were presented. As well-known, crack propagation, aggregation, and bifurcation play an critical role in the failure analysis of brittle materials such as shale. The dynamic crack propagation and branching analysis of shale by using the PD method were discussed. Firstly, the valid and accuracy of the PD model for the rock materials was verified by comparing with the existed numerical results. Secondly, we discussed the convergence both with uniform grid… More >

J. Sladek^1,2, V. Sladek¹, E. Pan³, D.L. Young⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.99, No.4, pp. 273-296, 2014, DOI:10.3970/cmes.2014.099.273

Abstract This paper presents a dynamic analysis of an anti-plane crack in functionally graded piezoelectric semiconductors. General boundary conditions and sample geometry are allowed in the proposed formulation. The coupled governing partial differential equations (PDEs) for shear stresses, electric displacement field and current are satisfied in a local weak-form on small fictitious subdomains. The derived local integral equations involve one order lower derivatives than the original PDEs. All field quantities are approximated by the moving least-squares (MLS) scheme. After performing spatial integrations, we obtain a system of ordinary differential equations for the involved nodal unknowns. It is noted that the stresses… More >

G. Kosec^1,2, P. Zinterhof³

CMES-Computer Modeling in Engineering & Sciences, Vol.91, No.5, pp. 377-396, 2013, DOI:10.3970/cmes.2013.091.377

Abstract This paper deals with the implementation of the local meshless numerical method (LMM) on general purpose graphics processing units (GPU) in solving partial differential equations (PDE). The local meshless solution procedure is formulated in a way suitable for parallel execution and has been implemented on multiple GPUs. The implementation is tested on a solution of diffusion equation in a 2D domain. Different setups of the meshless approach regarding the selection of basis functions are tested on an interval up to 2.5 million of computational points. It is shown that monomials are a good selection of the basis when working with… More >

Yantao Zhang¹, Xiong Zhang^1,2, Yan Liu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.69, No.2, pp. 143-166, 2010, DOI:10.3970/cmes.2010.069.143

Abstract Material point method(MPM) is a promising method in solving problems involving large deformations, especially explosion and penetration. In MPM, particles can move around the computing domain dynamically, which can result in load imbalance easily. In parallelizing MPM using OpenMP, data races will occur in the stage of grid node updating if we use loop-level parallelism for these loops. Huang et al. proposed a domain decomposition method to overcome data races [Huang, Zhang, Ma and Wang (2008)]. However, significant modifications of the original serial code are required. In this paper, we proposed a new alternated grid updating method to avoid data… More >

Linjun Wang¹, Xu Han², Youxiang Xie³

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.3&4, pp. 179-194, 2011, DOI:10.32604/cmes.2011.082.179

Abstract In this paper, a new homotopy perturbation method (IHPM) is presented and suggested to solve an ill-posed problem of multi-source dynamic loads reconstruction. We propose a stable and reliable modification, and obtain a new regularization method, then employ it to find the exact solution for the multi-source dynamic load identification problem. Also, this present method only needs easy computations rather than successive integrations. Finally, the performances of two numerical examples are given. Comparisons are performed between the original homotopy perturbation method (HPM) and IHPM. The results verify that the present method is very simple and effective. More >

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

CMES-Computer Modeling in Engineering & Sciences, Vol.68, No.2, pp. 185-220, 2010, DOI:10.3970/cmes.2010.068.185

Abstract A meshless method based on the local Petrov-Galerkin approach is proposed to solve initial-boundary value crack problems of piezoelectric solids with nonlinear electrical boundary conditions on crack faces. Homogeneous and continuously varying material properties of the piezoelectric solid are considered. Stationary governing equations for electrical fields and the elastodynamic equations with an inertial term for mechanical 2-D fields are considered. Nodal points are spread on the analyzed domain, and each node is surrounded by a small circle for simplicity. The spatial variation of displacements and electric potential are approximated by the Moving Least-Squares (MLS) scheme. After performing the spatial integrations,… More >

X.G. Yuan^1,2, H.W. Zhang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.40, No.3, pp. 201-224, 2009, DOI:10.3970/cmes.2009.040.201

Abstract The radially symmetric motion of the pre-existing micro-void centered at an incompressible hyperelastic sphere under the dynamic surface tensile loads relating to time is investigated in this paper. Some interesting conclusions are obtained by qualitatively analyzing the solutions of the motion equation of micro-void in detail; meanwhile, numerical simulations are used for understanding the obtained conclusions. In particular, it is proved that the motion of the micro-void with time would present a nonlinearly periodic oscillation if the values of the constant tensile load, the material and the structure parameters are given and that the oscillation amplitudes of the micro-void are… More >

K. Lee¹, H. Park², S.W. Lee³

CMES-Computer Modeling in Engineering & Sciences, Vol.32, No.3, pp. 113-122, 2008, DOI:10.3970/cmes.2008.032.113

Abstract A post-processing scheme is presented to accurately determine transverse shear and normal stresses in composite panels undergoing geometrically nonlinear deformation under dynamic loading conditions. Transverse stresses are assumed through thickness at a point of interest and are recovered via a one-dimensional finite element method. The finite element method is based on the least square functional of the error in the equilibrium equation along the thickness direction and utilizes the in-plane stresses and resultant transverse shear forces per unit length obtained by a shell element analysis. Numerical results demonstrate that, with minimal addition of computational efforts, the present post-processing approach can… More >