A.N.M. Imroz Choudhury¹, Michael D. Steffen¹, James E. Guilkey², Steven G.Parker³

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.2, pp. 117-136, 2010, DOI:10.3970/cmes.2010.063.117

Abstract We present a physically based method for visualizing deformation in particle simulations, such as those describing structural mechanics simulations. The method uses the deformation gradient tensor to transform carefully chosen glyphs representing each particle. The visualization approximates how simulated objects responding to applied forces might look in reality, allowing for a better understanding of material deformation, an important indicator of, for example, material failure. It can also help highlight possible errors and numerical deficiencies in the simulation itself, suggesting how simulations might be changed to yield more accurate results. More >

J.H. Tian^1,2, X. Han², S.Y. Long², G.Y. Sun², Y. Cao¹, G.Q. Xie³

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.2, pp. 101-116, 2010, DOI:10.3970/cmes.2010.063.101

Abstract A transient heat conduction analysis of the functionally graded material (FGM) plates has been investigated based on the hybrid numerical method (HNM). HNM combines the layer element method with the method of Fourier transforms and proves to be efficient and reliable. The FGM plates are infinite large and the material properties vary continuously through thickness. The transient heat source acted on the FGM plates. The temperature distribution of the FGM plates is obtained in different time and different position. Some useful results for transient heat conduction are shown in figures. Applications of HNM to transient More >

Alex Ferguson¹, Matthew R. Smith², J.-S. Wu³

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.1, pp. 79-100, 2010, DOI:10.3970/cmes.2010.063.079

Abstract A novel approach for the use of multiple continuous uniform distributions for reconstruction of the Maxwell-Boltzmann equilibrium probability distribution function is used for the solution of one and two dimensional Euler equations. The Uniform distribution Equilibrium Flux Method (UEFM) is a kinetic-theory based flux solver which calculates true directional, volume to volume fluxes based on integration (over velocity space and physical space) of a sum of uniform probability distribution functions working to approximate the equilibrium distribution function. The resulting flux expressions contain only the Heaviside unit step function and do not require the evaluation of More >

Roland Martin¹, Carlos Couder-Castaneda¹

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.1, pp. 47-78, 2010, DOI:10.3970/cmes.2010.063.047

Abstract We develop an unsplit convolutional perfectly matched layer (CPML) technique to absorb efficiently compressible viscous flows and their related supersonic or subsonic regimes at the outer boundary of a distorted computational domain. More particularly subsonic outgoing flows or subsonic wall-boundary layers close to the PML are well absorbed, which is difficult to obtain without creating numerical instabilities over long time periods. This new PML (CPML) introduces the calculation of auxiliary memory variables at each time step and allows an unsplit formulation of the PML. Damping functions involving a high shift in the frequency domain allow… More >

B.W. Kim¹, H.G. Sung¹, S.Y. Hong¹, H.J. Jung²

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.1, pp. 29-46, 2010, DOI:10.3970/cmes.2010.063.029

Abstract This paper numerically investigates the behavior of sag and tension of inclined catenary structure considering elastic deformation. Equilibrium equation for computing elastic catenary is formulated by employing finite element method (FEM). Minimum potential energy principle and the Lagrange multiplier method are used in the formulation to derive equilibrium equation with constraint condition for catenary length. Since stiffness and loading forces of catenary are dependent on its own geometry, the equilibrium equation is nonlinear. Using the iterative scheme such as fixed point iteration or bisection, equilibrium position and tension are found. Based on the formulation, a More >

Ching Kong Chao^1,2, Chin Kun Chen¹, Fu Mo Chen³

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.1, pp. 1-28, 2010, DOI:10.3970/cmes.2010.063.001

Abstract A general analytical solution for a reinforced elliptical hole embedded in an infinite matrix subjected to a point heat source is provided in this paper. Based on the technique of conformal mapping and the method of analytical continuation in conjunction with the alternating technique, the general expressions of the temperature and stresses in the reinforcement layer and the matrix are derived explicitly in a series form. Some numerical results are provided to investigate the effects of the material combinations and geometric configurations on the interfacial stresses. The solution obtained can be treated as Green's functions More >

Sung-Eun Kim¹, Shin Hyung Rhee²

CMES-Computer Modeling in Engineering & Sciences, Vol.62, No.3, pp. 291-310, 2010, DOI:10.3970/cmes.2010.062.291

Abstract Turbulent flow past a finite wing has been computed to assess the fidelity of modern computational fluid dynamics in predicting tip vortex flows. The efficacy of a feature-adaptive local mesh refinement to resolve the steep gradients in the flow field near the tip vortex is demonstrated. The impact of turbulence modeling is evaluated using several popular eddy viscosity models and a Reynolds stress transport model. The results indicate that the combination of a computational mesh with an adequate resolution, high-order spatial discretization scheme along with the use of advanced turbulence models can predict tip vortex More >

M. Tanaka^1,2, H. Noguchi¹, M. Fujikawa^3,4, M. Sato³, S. Oi³, T. Kobayashi³, K. Furuichi⁵, S. Ishimaru⁵, C. Nonomura⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.62, No.3, pp. 265-290, 2010, DOI:10.3970/cmes.2010.062.265

Abstract This paper describes the development of a proper constitutive model of woven fabrics and its implementation in nonlinear finite shell elements in order to simulate the large deformation behavior of cloth. This work currently focuses on a macroscopic continuum constitutive model that is capable of capturing the realistic mechanical behavior of cloth that is characterized by two families of yarns, i.e., warp and weft. In this study, two strategies are considered. One is a rebar layer model and the other is a polyconvex anisotropic hyperelastic material model. The latter avoids non-physical behavior and can consider More >

Mustafa Yidiz¹, Bayram Heydarov², İsmet Gölgeleyen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.62, No.3, pp. 255-264, 2010, DOI:10.3970/cmes.2010.062.255

Abstract We investigate the solvability of an inverse problem for the non-stationary general kinetic equation. We also obtained the approximate solution of this problem by using symbolic computation. A comparison between the approximate solution and the exact solution of the problem is presented. More >

Huan J. Keh¹, Yu C. Chang²

CMES-Computer Modeling in Engineering & Sciences, Vol.62, No.3, pp. 225-254, 2010, DOI:10.3970/cmes.2010.062.225

Abstract A theoretical study of the Stokes flow caused by a rigid particle of revolution translating axisymmetrically perpendicular to two parallel plane walls at an arbitrary position between them in a viscous fluid, which may slip at the particle surface, is presented. A method of distribution of a set of spherical singularities along the axis of revolution within a prolate particle or on the fundamental plane within an oblate particle is used to find the general solution of the fluid velocity field that satisfies the boundary conditions at the plane walls and at infinity. The slip… More >