L. Godinho¹, D. Soares Jr.²

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.4, pp. 327-354, 2012, DOI:10.3970/cmes.2012.087.327

Abstract In this work, a coupling strategy between the Method of Fundamental Solutions (MFS) and the Kansa's Method (KM) for the analysis of fluid-solid interaction problems in the frequency domain is proposed. In this approach, the MFS is used to model the acoustic fluid medium, while KM accounts for the elastodynamic solid medium. The coupling between the two methods is performed iteratively, with independent discretizations being used for the two methods, without requiring matching between the boundary nodes along the solid-fluid interface. Two application examples, with single and multiple solid sub-domains, are presented, illustrating the behavior of the proposed approach. More >

Y. Hu¹, T. Wei^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.4, pp. 307-326, 2012, DOI:10.3970/cmes.2012.087.307

Abstract This paper employ the method of fundamental solutions for determining an unknown heat source term in a heat equation from overspecified boundary measurement data. By a function transformation, the inverse source problem is changed into an inverse initial data problem which is solved by a method of fundamental solutions. The standard Tikhonov regularization technique with the generalized cross-validation criterion for choosing the regularization parameter is adopted for solving the resulting ill-conditioned system of linear algebraic equations. The effectiveness of the algorithm is illustrated by five numerical examples in one-dimensional and two-dimensional cases. More >

M. Khezri¹, Z. Vrcelj¹, M.A. Bradford^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.4, pp. 271-306, 2012, DOI:10.3970/cmes.2012.087.271

Abstract A finite strip method (FSM) utilising the generalised reproducing kernel particle method (RKPM) [Behzadan, Shodja, and Khezri (2011)] is developed for the bending analysis of thin plates. In this innovative approach, the spline functions in the conventional spline finite strip method (SFSM) are replaced with generalised RKPM 1-D shape functions in the longitudinal direction, while the transverse cubic functions which are used in the conventional formulations are retained. Since the generalised RKPM is one of the class of meshfree methods which deal efficiently with derivative-type essential boundary conditions, its introduction in the FSM is beneficial for solving boundary value problems… More >

Taicong Chen¹, Haitao Ma¹, Wei Gao²

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.3, pp. 239-270, 2012, DOI:10.3970/cmes.2012.087.239

Abstract Monte Carlo simulation method has been used extensively in probabilistic analyses of engineering systems and its popularity has been growing. While it is widely accepted that the simulation results are asymptotically accurate when the number of samples increases, certain exceptions do exist. The major objectives of this study are to reveal the conditions of the applicability of Monte Carlo method and to provide new insights into the accuracy of the simulation results in stochastic structural analysis. Firstly, a simple problem of a spring with random axial stiffness subject to a deterministic tension is investigated, using normal and lognormal distributions. Analytical… More >

K.H. Zheng¹, H.W. Ma^2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.3, pp. 225-238, 2012, DOI:10.3970/cmes.2012.087.225

Abstract Based on the analogy equation method and method of particular solutions, we propose a combined boundary knot method (CBKM) for solving nonlinear problems in this paper. The principle of the CBKM lies in that the analogy equation method is used to convert the nonlinear governing equation into a corresponding linear inhomogeneous one under the same boundary conditions. Then the method of particular solutions and boundary knot method are, respectively, used to construct the particular and homogeneous solutions for the newly-introduced inhomogeneous equation. Finally, the field function and its derivatives involved in the nonlinear governing equation are expressed via the unknown… More >

P.P. Prochazka¹, M.J. Valek¹

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.3, pp. 207-224, 2012, DOI:10.3970/cmes.2012.087.207

Abstract In classical theories of homogenization and localization of composites the effect of shape of inclusions is not taken into account. This is probably done because of very small fibers in classical composites based on epoxy matrix. Applying more precise theoretical and numerical tools appears that the classical theories desire corrections in this direction. Today many types of materials their fiber are much bigger and with various material properties are used and behave as typical composites. They enable producers to create the fiber cross-sections and model them in various shapes, so that it is meaningful to carry out the optimization. In… More >

A.E. Martínez-Castro¹, I.H. Faris¹, R. Gallego¹

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.3, pp. 177-206, 2012, DOI:10.3970/cmes.2012.087.177

Abstract In this paper, the identification of hidden defects inside a three-dimen -sional layer is set as an Identification Inverse Problem. This problem is solved by minimizing a cost functional which is linearized with respect to the volume defects, leading to a procedure that requires only computations at the host domain free of defects. The cost functional is stated as the misfit between experimental and computed displacements and spherical and/or ellipsoidal cavities are the defects to locate. The identification of these cavities is based on the measured displacements at a set of points due to time-harmonic point loads at an array… More >

A. Sellier

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.2, pp. 157-176, 2012, DOI:10.3970/cmes.2012.087.157

Abstract A new approach is proposed to accurately compute at a reasonable cpu time cost the hydrodynamic net force and net torque exerted on a slip and arbitrarily-shaped solid particle experiencing a prescribed slow rigid-body migration in a quiescent Newtonian liquid. The advocated method appeals to a boundary formulation which makes it possible to reduce the task to the treatment of a relevant regularized boundary-integral equation on the particle slipping surface. This integral equation is numerically inverted by implementing a boundary element collocation method. In addition to benchmark tests against analytical and numerical results available in the literature, numerical results for… More >

L. Rodríguez-Tembleque¹, R. Abascal¹, M.H. Aliabadi²

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.2, pp. 127-156, 2012, DOI:10.3970/cmes.2012.087.127

Abstract A boundary element based formulation is proposed to simulate 3D fretting wear under gross-sliding and partial slip conditions, assuming anisotropic friction and wear laws. Contact problem is based on an Augmented Lagrangian formulation, and restrictions fulfilment is established by a set of projection functions. The boundary element method reveals to be a very suitable numerical method for this kind of problems, where the degrees of freedom involved are those on the solids surfaces, and a very good approximation on contact tractions is obtained with a low number of elements. The present boundary element anisotropic fretting wear formulation is illustrated with… More >