Open Access
ARTICLE
N. Simões1,2, A. Tadeu2
CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.3, pp. 221-234, 2005, DOI:10.3970/cmes.2005.009.221
Abstract The use of the Boundary Element Method (BEM) to formulate the 3D transient heat transfer through cylindrical structures with irregular cross-sections, bounded by a homogeneous elastic medium, is described in this paper. In this formulation, both the conduction and the convection phenomena are modeled. This system can be subjected to heat emitted by either point or line sources located somewhere in the media. The solution is first obtained in the frequency domain for a wide range of frequencies and axial wavenumbers. Time domain responses are later calculated by means of (fast) inverse Fourier transforms into space-time. The appropriate fundamental solution… More >
Open Access
ARTICLE
T.Tsukiji1, Y.Yamamoto2
CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.3, pp. 235-242, 2005, DOI:10.3970/cmes.2005.009.235
Abstract The grid free computational model of gas-particle two-phase jet flow using a 3-D vortex method is presented. The calculated results using the present method are compared with the previous experimental and the calculated results using DNS. The interaction between the particle and gas-phase is considered using Lagrangian method. It is found that the present computational model of gas-particle two-phase jet flow using the 3-D vortex method is very useful for the prediction of the physical properties of the two-phase jet flow and for saving the computational time. More >
Open Access
ARTICLE
B. Chandrasekhar1
CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.3, pp. 243-254, 2005, DOI:10.3970/cmes.2005.009.243
Abstract In this work, a novel numerical technique is presented to calculate the acoustic fields scattered by three dimensional rigid bodies of arbitrary shape using the method of moment's solution procedure. A new set of basis functions, namely, Node based basis functions are developed to represent the source distribution on the surface of rigid body and the same functions are used as testing functions as well. Both single layer formulation and double layer formulations are numerically solved using the same basis functions. The surface of the body is modeled by triangular patch modeling. Numerical technique presented in this paper, using these… More >
Open Access
ARTICLE
Chein-Shan Liu1
CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.3, pp. 255-272, 2005, DOI:10.3970/cmes.2005.009.255
Abstract The group-preserving scheme developed by Liu (2001) for calculating the solutions of k-dimensional differential equations system adopted the Cayley transform to formulate the Lie group from its Lie algebra A ∈ so(k,1). In this paper we consider a more effective exponential mapping to derive exp(hA). In order to overcome the difficulty of numerical instabilities encountered by employing group-preserving schemes on stiff differential equations, we further combine the nonstandard finite difference method into the group-preserving schemes to obtain unconditional stable numerical methods. They provide single-step explicit time integrators for stiff differential equations. Several numerical examples are examined, some of which are… More >
Open Access
ARTICLE
Feng Zhao1, Song-Ping Zhu2, Zhi-Rong Zhang1
CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.3, pp. 273-286, 2005, DOI:10.3970/cmes.2005.009.273
Abstract In this paper, the steady viscous flow around a ship hull with free surface is studied through solving Reynolds Averaged Navier-Stokes (RANS) equations numerically. The RANS solver is based on a cell-centered finite-volume discretization. In our study, the turbulence is modeled through an SST (Shear Stress Transport) k - ω turbulence model in conjunction with the wall function approach for the near-wall simulation. The VOF method is used for the free surface treatment. Calculations for two typical benchmark surface ship models, Wigley and DTMB 5415, are carried out first for the purpose of model validation. The numerical results are compared… More >
Open Access
ARTICLE
S.C. Forth1, A. Staroselsky2
CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.3, pp. 287-298, 2005, DOI:10.3970/cmes.2005.009.287
Abstract A new hybrid surface-integral-finite-element numerical scheme has been developed to model a three-dimensional crack propagating through a thin, multi-layered coating. The finite element method was used to model the physical state of the coating, and the surface integral method was used to model the fatigue crack growth. The two formulations are coupled through the need to satisfy boundary conditions on the crack and external surface. The coupling is sufficiently weak that the surface integral mesh of the crack surface and the finite element mesh of the uncracked volume can be set up independently. Thus, when modeling crack growth, the finite… More >