Jin Li^1,2, De-hao Yu^3,4

CMES-Computer Modeling in Engineering & Sciences, Vol.102, No.2, pp. 103-126, 2014, DOI:10.3970/cmes.2014.102.103

Abstract The generalized composite middle rectangle rule for the computation of Hilbert integral is discussed. The pointwise superconvergence phenomenon is presented, i.e., when the singular point coincides with some a priori known point, the convergence rate of the rectangle rule is higher than what is global possible. We proved that the superconvergence rate of the composite middle rectangle rule occurs at certain local coordinate of each subinterval and the corresponding superconvergence error estimate is obtained. By choosing the superconvergence point as the collocation points, a collocation scheme for solving the relevant Hilbert integral equation is presented More >

Christina Babenko¹, Roman Chapko², B. Tomas Johansson³

CMES-Computer Modeling in Engineering & Sciences, Vol.101, No.5, pp. 299-317, 2014, DOI:10.3970/cmes.2014.101.299

Abstract We consider the numerical solution of the Laplace equations in planar bounded domains with corners for two types of boundary conditions. The first one is the mixed boundary value problem (Dirichlet-Neumann), which is reduced, via a single-layer potential ansatz, to a system of well-posed boundary integral equations. The second one is the Cauchy problem having Dirichlet and Neumann data given on a part of the boundary of the solution domain. This problem is similarly transformed into a system of ill-posed boundary integral equations. For both systems, to numerically solve them, a mesh grading transformation is More >

P.H. Wen¹, X.J. Huang¹, M.H. Aliabadi²

CMES-Computer Modeling in Engineering & Sciences, Vol.96, No.3, pp. 199-225, 2013, DOI:10.3970/cmes.2013.096.199

Abstract In this paper, a Local Integral Equation Method (LIEM) is presented for solving two-dimensional nonlocal elasticity problems . The approach is based on the Eringen’s model with LIEM and the interpolation using the radial basis functions to obtain the numerical solutions for 2D problems. A weak form for the set of governing equations with a unit test function is transformed into the local integral equations. The meshless approximation technique with radial basis functions is employed for the implementation of displacements. A set of the local domain integrals is obtained in analytical form for the local More >

A. Sellier

CMES-Computer Modeling in Engineering & Sciences, Vol.96, No.3, pp. 159-176, 2013, DOI:10.3970/cmes.2013.096.159

Abstract The rigid-body migration of a slip and arbitrary-shaped solid particle freely suspended in a prescribed and arbitrary ambient Stokes flow is determined after calculating the hydrodynamic force and torque exerted on the particle when it either experiences a given rigid-body in a quiescent liquid or is held fixed in the ambient Stokes flow. It is also shown how one can subsequently obtain the velocity and surface traction on the particle boundary and thereafter, if necessary, the flow about the particle in the entire liquid domain. The advocated procedure extends a recent work (see Sellier (2012)) More >

Ji-Chuan Liu¹, Quan-Guo Zhang²

CMES-Computer Modeling in Engineering & Sciences, Vol.93, No.3, pp. 203-220, 2013, DOI:10.3970/cmes.2013.093.203

Abstract In this paper, we propose an algorithm to solve a Cauchy problem of the Laplace equation in doubly connected domains for 2D and 3D cases in which the Cauchy data are given on the outer boundary. We want to seek a solution in the form of the single-layer potential and discrete it by parametrization to yield an ill-conditioned system of algebraic equations. Then we apply the Tikhonov regularization method to solve this ill-posed problem and obtain a stable numerical solution. Based on the regularization parameter chosen suitably by GCV criterion, the proposed method can get More >

C.K. Chao¹, A. Wikarta²

CMES-Computer Modeling in Engineering & Sciences, Vol.93, No.3, pp. 167-186, 2013, DOI:10.3970/cmes.2013.093.167

Abstract In this paper a crack interacting with tri-material composite under a remote uniform tensile load is solved in plane elasticity. An edge dislocation distribution along the prospective site of the crack together with the principle of superposition is used to model a crack. The resulting singular integral equation with logarithmic singular kernels for a line crack is then established. The singular integral equation is solved numerically by modeling a crack in place of several segments. Linear interpolation formulae with undetermined coefficients are applied to approximate the dislocation distribution along the elements, except at vicinity of More >

P. K. Sahu¹, S. Saha Ray^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.93, No.2, pp. 91-112, 2013, DOI:10.3970/cmes.2013.093.091

Abstract In this paper, nonlinear integral equations have been solved numerically by using B-spline wavelet method and Variational Iteration Method (VIM). Compactly supported semi-orthogonal linear B-spline scaling and wavelet functions together with their dual functions are applied to approximate the solutions of nonlinear Fredholm integral equations of second kind. Comparisons are made between the variational Iteration Method (VIM) and linear B-spline wavelet method. Several examples are presented to compare the accuracy of linear B-spline wavelet method and Variational Iteration Method (VIM) with their exact solutions. More >

Xianhui Wang¹, Jianming Zhang^1,2, Xingshuai Zheng¹, Fenglin Zhou¹

CMES-Computer Modeling in Engineering & Sciences, Vol.93, No.1, pp. 69-90, 2013, DOI:10.3970/cmes.2013.093.069

Abstract In this paper, a half space adaptive fast multipole boundary face method (FMBFM) is presented for solving the three-dimensional half space exterior acoustic problems. In the presented method, the Burton-Miller equation based on the conventional boundary integral equation (CBIE) and its hyper-singular boundary integral equation (HBIE) is used to deal with the fictitious eigenfrequencies problem. The half space Green’s function is employed, thus the tree structure in the fast multipole method can be used only for the real domain. The higher order elements and an adaptive tree structure are used to improve the efficiency of More >

A.V. Ekhlakov^1,2, O.M. Khay^1,3, Ch. Zhang¹, X.W. Gao⁴, J. Sladek⁵, V. Sladek⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.92, No.6, pp. 595-614, 2013, DOI:10.3970/cmes.2013.092.595

Abstract A boundary-domain integral equation method is applied to the transient thermoelastic crack analysis in functionally graded materials. Fundamental solutions for homogeneous, isotropic and linear elastic materials are used to derive the boundary-domain integral equations. The radial integration method, the Cartesian transformation method and the cell-integration method are applied for the evaluation of the arising domain-integrals. Numerical results for dynamic stress intensity factors obtained by the three approaches are presented, compared and discussed to show the accuracy and the efficiency of the domain-integral evaluation techniques. More >

Shou-Zhong Fu¹, Zhong Wang¹, Jun-Sheng Duan^1,2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.92, No.4, pp. 369-385, 2013, DOI:10.3970/cmes.2013.092.369

Abstract Quadratic integral equations are a class of nonlinear integral equations having many important uses in engineering and sciences. In this work we display an efficient application of the Adomian decomposition method to the quadratic integral equations of Volterra type. The analytical approximate solution obtained can be directly inserted into the original equation to verify the accuracy and estimate the error with a computing software. Four numerical examples demonstrate the efficiency of the method. More >