V.K. Tewary

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 113-114, 2011, DOI:10.3970/icces.2011.019.113

Abstract Interfacial region between two nanomaterials can be treated as a separate material since its atomistic structure and characteristics are different than the two materials on its either side. The mechanical as well as electronic properties of composite materials are sensitive to the interfaces. For industrial application of the nanomaterial systems, it is vital to model and measure the discrete atomistic locations in the interface during operating conditions. As the dimensions of nanomaterial systems shrink, the role of interfaces become increasingly important. Because of its nanothickness, the conventional characterization and design parameters like elastic constants, stress… More >

Wei-Ming Lee, Jyun-Sian He, Jhong-Sian Guo

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 65-66, 2011, DOI:10.3970/icces.2011.018.065

Abstract A semi-analytical approach is presented to solve two-dimensional interior and exterior acoustic problems with elliptical boundaries. The eigenproblems for the interior domain and the scattering problems for the exterior domain are both to be investigated. To satisfy the Helmholtz equation in elliptical coordinates, the multipole expansion for the acoustic pressure is formulated in terms of angular and radial Mathieu functions. The boundary conditions are satisfied by uniformly collocating points on the boundaries. The acoustic pressure at each boundary point is directly calculated in each local elliptical coordinate system. For the multiply connected domain problems, the… More >

H.F. Chan, C.M. Fan

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.1, pp. 29-30, 2011, DOI:10.3970/icces.2011.019.029

Abstract The inverse boundary optimization problem, which is governed by Helmholtz equation, is analyzed by the modified collocation Trefftz method (MCTM) and the exponentially convergent scalar homotopy algorithm (ECSHA). In the inverse boundary optimization problem, the position for part of boundary with given boundary condition is unknown, and the position for the rest of boundary with additionally specified boundary conditions is given. Therefore, it is very difficult to handle the boundary optimization problem by any numerical scheme. In order to stably solve the boundary optimization problem, the MCTM, one kind of boundary-type meshless methods, will be… More >

Yansheng He, Qingchuan Zhang, Shihua Fu, Qi Hu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.1, pp. 5-6, 2011, DOI:10.3970/icces.2011.018.005

Abstract Abstract: The interaction of dislocation and solute atoms has great influence on the macroscopic mechanical behavior in alloys as well as the deformation of alloys. A dynamic Monte Carlo method is developed to simulate the interaction between dislocation and solute atom. The results show that dislocation motion is retarded by solute atoms in certain conditions. In the condition of constant external stress, the retarding effect of solute atoms becomes more inefficient with the increment of external stress. In the condition of constant stress rate, a step-like curve of the displacement-time indicates the intermittent motion of… More >

G. Kosec¹, B. Šarler^1,2

CMC-Computers, Materials & Continua, Vol.26, No.3, pp. 227-254, 2011, DOI:10.3970/cmc.2011.026.227

Abstract This paper introduces an effective H-adaptive upgrade to solution of the transport phenomena by the novel Local Radial Basis Function Collocation Method (LRBFCM). The transport variable is represented on overlapping 5-noded influence-domains through collocation by using multiquadrics Radial Basis Functions (RBF). The involved first and second derivatives of the variable are calculated from the respective derivatives of the RBFs. The transport equation is solved through explicit time stepping. The H-adaptive upgrade includes refinement/derefinement of one to four nodes to/from the vicinity of the reference node. The number of the nodes added or removed depends on… More >

L. Dong¹, S. N. Atluri²

CMES-Computer Modeling in Engineering & Sciences, Vol.81, No.1, pp. 69-118, 2011, DOI:10.3970/cmes.2011.081.069

Abstract In this paper, we explore three different ways of developing T-Trefftz finite elements of quadrilateral as well as polygonal shapes. In all of these three approaches, in addition to assuming an inter-element compatible displacement field along the element boundary, an interior displacement field for each element is independently assumed as a linear combination of T-Trefftz trial functions. In addition, a characteristic length is defined for each element to scale the T-Trefftz modes, in order to avoid solving systems of ill-conditioned equations. The differences between these three approaches are that, the compatibility between the independently assumed… More >

V. Kozulić¹, B. Gotovac¹

CMES-Computer Modeling in Engineering & Sciences, Vol.80, No.3&4, pp. 251-274, 2011, DOI:10.3970/cmes.2011.080.251

Abstract The numerical model for the elasto-plastic analysis of prismatic bars subjected to torsion is developed. The functions implemented in this model are Fup basis functions which belong to the class of atomic functions. The collocation method is used to form a system of equations in which the differential equation of the problem is satisfied in collocation points of closed domain, while boundary conditions are satisfied exactly at the domain boundary. The propagation of plastic zones in the cross-section is monitored by applying the incremental-iterative procedure until failure. An approximate solution of arbitrary accuracy is attained More >

D.-A. An-Vo¹, N. Mai-Duy¹, T. Tran-Cong¹

CMES-Computer Modeling in Engineering & Sciences, Vol.80, No.2, pp. 141-178, 2011, DOI:10.3970/cmes.2011.080.141

Abstract In this paper, 2-node integrated radial basis function elements (IRBFEs) [CMES, vol.72, no.4, pp.299-334, 2011] are further developed for the simulation of incompressible viscous flows in two dimensions. Emphasis is placed on (i) the incorporation of C²-continuous 2-node IRBFEs into the subregion and point collocation frameworks for the discretisation of the stream function-vorticity formulation on Cartesian grids; and (ii) the development of high order upwind schemes based on 2-node IRBFEs for the case of convection-dominant flows. High levels of accuracy and efficiency of the present methods are demonstrated by solutions of several benchmark problems defined on More >

Yi W. Wan¹, Huan J. Keh²

CMES-Computer Modeling in Engineering & Sciences, Vol.74, No.2, pp. 109-138, 2011, DOI:10.3970/cmes.2011.074.109

Abstract The steady rotation of an axially symmetric particle about its axis of revolution normal to two plane walls at an arbitrary position between them in a viscous fluid is studied theoretically in the limit of small Reynolds number. The fluid is allowed to slip at the surface of the particle. A method of distribution of a set of spherical singularities along the axis of revolution inside a prolate particle or on the fundamental disk within an oblate particle is used to find the general solution for the fluid velocity distribution that satisfies the boundary conditions… More >

Y.-M. Guo ¹

CMES-Computer Modeling in Engineering & Sciences, Vol.73, No.1, pp. 1-22, 2011, DOI:10.3970/cmes.2011.073.001

Abstract In this paper, a new meshless method called the overrange collocation method (ORCM) is proposed. By introducing some collocation points, which are located at outside of domain of the analyzed body, unsatisfactory issue of the positivity conditions of boundary points in collocation methods can be avoided. Because the overrange points are used only in interpolating calculation, no over-constrained condition is imposed into the solved boundary value problems. Poisson's problem and the linear elastic cantilever beam problem are analyzed by using the ORCM. More >