Open Access
ARTICLE
H.Nguyen-Van1, N.Mai-Duy1 and T.Tran-Cong1
CMES-Computer Modeling in Engineering & Sciences, Vol.49, No.2, pp. 81-112, 2009, DOI:10.3970/cmes.2009.049.081
Abstract This paper reports the development of a simple and efficient 4-node flat shell element with six degrees of freedom per node for the analysis of arbitrary shell structures. The element is developed by incorporating a strain smoothing technique into a flat shell finite element approach. The membrane part is formulated by applying the smoothing operation on a quadrilateral membrane element using Allman-type interpolation functions with drilling DOFs. The plate-bending component is established by a combination of the smoothed curvature and the substitute shear strain fields. As a result, the bending and a part of membrane stiffness matrices are computed on… More >
Open Access
ARTICLE
J.M.C.Pereira1, N.A.R.Maia1, J.C.F.Pereira1
CMES-Computer Modeling in Engineering & Sciences, Vol.49, No.2, pp. 113-142, 2009, DOI:10.3970/cmes.2009.049.113
Abstract We present a 2D incompressible Navier-Stokes numerical simulation of a virtual model of an elliptic, or flat plate, foil in hovering flight configuration. Computations obtained with a general purpose solver were validated against reference data on forward flapping flight, normal or dragonfly hovering. The moving mesh technique allows airfoil translation and angular mesh movement accompaining the airfoil stroke motion. Close to the ground the mesh deforms to occupy the narrow computational domain formed between the airfoil and the ground. Computations have been carried out for some parameters, including the distances h between the foil center and the surface, h/c =… More >
Open Access
ARTICLE
K. Han1, Y. T. Feng1, D. R. J. Owen1
CMES-Computer Modeling in Engineering & Sciences, Vol.49, No.2, pp. 143-162, 2009, DOI:10.3970/cmes.2009.049.143
Abstract Motivated by Hottel's crossed-string method, this paper presents an accurate algorithm for the evaluation of the geometric view factors in a randomly packed bed of circular particles of various sizes. The radiative heat exchange can thus be predicted accurately. The solution procedure is illustrated and the solution accuracy is assessed via a numerical example. More >
Open Access
ARTICLE
Ronan Madec1, Dimitri Komatitsch1,2, Julien Diaz3
CMES-Computer Modeling in Engineering & Sciences, Vol.49, No.2, pp. 163-190, 2009, DOI:10.3970/cmes.2009.049.163
Abstract When studying seismic wave propagation in fluid-solid models based on a numerical technique in the time domain with an explicit time scheme it is often of interest to resort to time substepping because the stability condition in the solid part of the medium can be more stringent than in the fluid. In such a case, one should enforce the conservation of energy along the fluid-solid interface in the time matching algorithm in order to ensure the accuracy and the stability of the time scheme. This is often not done in the available literature and approximate techniques that do not enforce… More >