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 >

Chih-Ping Wu^1,2, Hao-Yuan Li¹

CMC-Computers, Materials & Continua, Vol.34, No.1, pp. 27-62, 2013, DOI:10.3970/cmc.2013.034.027

Abstract A Reissner's mixed variational theorem (RMVT)-based finite rectangular prism method (FRPM) is developed for the three-dimensional (3D) analysis of sandwich functionally graded material (FGM) plates subjected to mechanical loads, in which the edge conditions of the plates are such that one pair of opposite edges is simply supported and the other pair may be combinations of free, clamped or simply supported edges. The sandwich FGM plate considered consists of two thin and stiff homogeneous material face sheets combined with an embedded thick and soft FGM core, the material properties of which are assumed to obey… 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 More >

G. Mattei^1,2, A. Tirella^1,2, A. Ahluwalia^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.6, pp. 483-504, 2012, DOI:10.3970/cmes.2012.087.483

Abstract Biological function is intricately linked with structure. Many biological structures are characterised by functional spatially distributed gradients in which each layer has one or more specific functions to perform. Reproducing such structures is challenging, and usually an experimental trial-and-error approach is used. In this paper we investigate how the gravitational sedimentation of discrete solid particles (secondary phase) within a primary fluid phase with a time-varying dynamic viscosity can be used for the realisation of stable and reproducible continuous functionally graded materials (FGMs). Computational models were used to simulate the distribution of a particle phase in… More >

Kowal-Michalska K., Mania R.J.

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.2, pp. 55-56, 2011, DOI:10.3970/icces.2011.016.055

Abstract The static and dynamic buckling analysis is conducted for functionally graded composite plates under edgewise compression. The rectangular FGM plates with simply supported edges are studied. In the applied model the material properties vary continuously in the thickness direction according to a simple power law distribution in terms of constituents - it is the ceramic and metal volume fractions. The analyzed plate is composed of ceramic (zirconia or TiC) and metal (steel or aluminum, respectively) phases. Different through-thickness mechanical material properties have been modeled by the volume fraction exponent of value in the range of… More >

D. Mirzaei¹, M. Dehghan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.72, No.3, pp. 185-210, 2011, DOI:10.3970/cmes.2011.072.185

Abstract The meshless local Petrov-Galerkin (MLPG) method with an efficient technique to deal with the time variable are used to solve the heat conduction problem in this paper. The MLPG is a meshless method which is (mostly) based on the moving least squares (MLS) scheme to approximate the trial space. In this paper the MLS is used for approximation in both time and space domains, and we avoid using the time difference discretization or Laplace transform method to overcome the time variable. The technique is applied for continuously nonhomogeneous functionally graded materials (FGM) in a finite More >

Chih-Ping Wu^1,2, Hao-Yuan Li²

CMC-Computers, Materials & Continua, Vol.19, No.2, pp. 155-198, 2010, DOI:10.3970/cmc.2010.019.155

Abstract The Reissner mixed variational theorem (RMVT)- and principle of virtual displacements (PVD)-based finite layer methods (FLMs) are developed for the quasi-three-dimensional (3D) free vibration analysis of simply-supported, multilayered composite and functionally graded material (FGM) plates. The material properties of the FGM layers are assumed to obey either an exponent-law exponentially varied with the thickness coordinate or the power-law distributions of the volume fractions of the constituents. In these formulations, the plate is divided into a number of finite layers, where the trigonometric functions and Lagrange polynomials are used to interpolate the in- and out-of-plane variations… More >

Ch.Raghuveer¹, Mohit Pant¹, I.V. Singh¹, B.K. Mishra¹, V. Bhasin², Kamal Sharma², I.A. Khan²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.1, pp. 23-32, 2009, DOI:10.3970/icces.2009.012.023

Abstract In this work, element free Galerkin method (EFGM) has been applied to solve solid mechanics problems containing material discontinuities. The method is based on treatment of interface conditions at the variational level. Modifications are made in the EFGM to incorporate material discontinuities, which include the variational form of the governing differential equations. Two bi-material problems i.e. beam and bar has been solved using EFGM, and a clear discontinuity in the stress field has been observed at the interface of two materials. More >

Mohit Pant¹, I. V. Singh¹, B. K. Mishra¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.1, pp. 13-22, 2009, DOI:10.3970/icces.2009.012.013

Abstract In this work, element free Galerkin method (EFGM) has been used to obtain the solution of centre crack problem under thermo-mechanical loads as it provides a versatile technique to model static as well as moving crack problems without any requirement of re-meshing. Diffraction criterion has been used to model crack geometry. The effect of crack orientation of centre crack has been studied under both mechanical and equivalent thermal loading under plane stress conditions. The values of mode-I and mode-II stress intensity factors have been evaluated by the interaction integral approach. More >

H. T. Xiao¹, Z. Q. Yue²

CMES-Computer Modeling in Engineering & Sciences, Vol.52, No.2, pp. 159-180, 2009, DOI:10.3970/cmes.2009.052.159

Abstract This paper presents a three-dimensional boundary element method for contact problems of an elastic indenter on the surface of functionally graded materials (FGMs). The FGM elastic properties can have any irregular variations with depth. The indenter is subjected to the loading normal to the flat contact surface. The classical Kelvin solution is used for the mathematical formulation of the homogeneous elastic indenter. The generalized Kelvin solution is used for the mathematical formulation of the FGM base. The contact variables are defined with respect to each of the surfaces using local coordinate systems. The corresponding contact More >