A. Behjatian¹, A. Esmaeeli¹

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.3, pp. 299-317, 2014, DOI:10.3970/fdmp.2014.010.299

Abstract Computational studies are performed to explore the underlying physics behind the evolution of the flow field in an around a liquid jet that is immersed in another liquid and is exposed to a uniform electric field. Here the focus is on finite Reynolds and O(1) Ohnesorge number flows. This is achieved by solving the full Navier-Stokes and electric field equations using a front tracking/finite difference technique in the framework of Taylor's leaky dielectric theory. It is shown that the evolution of the flow field is determined by the relative magnitude of the ratio of the electric conductivity R = σ_i/σ_o… More >

Md. Abdul Halim¹, Asghar Esmaeeli²

FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.4, pp. 435-460, 2013, DOI:10.3970/fdmp.2013.009.435

Abstract This study aims to gain a detailed understanding of the transient behavior of solitary liquid drops in electric fields at finite Reynolds number. A front tracking/finite difference method, in conjunction with Taylor-Melcher leaky dielectric model, is used to solve the governing electrohydrodynamic equations. The evolution of the flow field and drop deformation is studied for a few representative fluid systems, corresponding to the different regions of the deformation-circulation map. It is shown that for the range of the physical parameters used here, the deformationtime history is governed by one time scale while the fluid flow (characterized by kinetic energy) is… More >

A. Merabtine¹, S. Mokraoui¹, R. Benelmir¹, N. Laraqi²

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.2, pp. 215-240, 2012, DOI:10.3970/fdmp.2012.008.215

Abstract Modeling of the thermal behavior of buildings needs effective strategies of analysis and tools. This is particularly true when conduction of heat through walls and/or slabs has to be properly taken into account. This article is concerned with a new modeling strategy for solving the transient heat conduction equation in a finite medium (with extensive background application to the different elements of a building structure). The developed approach is based on the Bond Graph technique, a graphical modeling language which is particularly suitable to the treatment of problems involving energy transfer. With this model, two typical transient heat conduction situations… More >

J. Sladek¹, V. Sladek¹, Ch. Zhang², F. Garcia-Sanche³, M. Wünsche²

CMC-Computers, Materials & Continua, Vol.4, No.2, pp. 109-118, 2006, DOI:10.3970/cmc.2006.004.109

Abstract Piezoelectric materials have wide range engineering applications in smart structures and devices. They have usually anisotropic properties. Except this complication electric and mechanical fields are coupled each other and the governing equations are much more complex than that in the classical elasticity. Thus, efficient computational methods to solve the boundary or the initial-boundary value problems for piezoelectric solids are required. In this paper, the Meshless local Petrov-Galerkin (MLPG) method with a Heaviside step function as the test functions is applied to solve two-dimensional (2-D) piezoelectric problems. The mechanical fields are described by the equations of motion with an inertial term.… More >

Haolong Chen^1,2, Bo Yu¹, Huanlin Zhou^1*, Zeng Meng¹

CMC-Computers, Materials & Continua, Vol.53, No.4, pp. 271-290, 2017, DOI:10.3970/cmc.2017.053.271

Abstract The cuckoo search algorithm (CS) is improved by using the conjugate gradient method(CGM), and the CS-CGM is proposed. The unknown inner boundary shapes are generated randomly and evolved by Lévy flights and elimination mechanism in the CS and CS-CGM. The CS, CGM and CS-CGM are examined for the prediction of a pipe’s inner surface. The direct problem is two-dimensional transient heat conduction in functionally graded materials (FGMs). Firstly, the radial integration boundary element method (RIBEM) is applied to solve the direct problem. Then the three methods are compared to identify the pipe’s inner surfacewith the information of measured temperatures. Finally,… More >

A. Ramachandra Murthy¹, G.S. Palani¹, Smitha Gopinath¹, V. Ramesh Kumar¹, Nagesh R. Iyer¹

CMC-Computers, Materials & Continua, Vol.37, No.2, pp. 77-96, 2013, DOI:10.3970/cmc.2013.037.077

Abstract This paper presents the development of an improved concrete damage model for projectile impact on concrete structural components. The improvement is in terms of reduction of input material parameters for nonlinear transient dynamic impact analysis by employing concrete damage model. The experimental data such as pressure vs volumetric strain, triaxial compression failure and pressure vs stress difference have been used for evaluation of the important parameters of concrete damage model. Various contact algorithms have been outlined briefly to model the interface between the projectile and target. The nonlinear explicit transient dynamic analysis has been carried out by using finite element… More >

Yi-Hsien Lin¹, Chien-Ching Ma^1,2

CMC-Computers, Materials & Continua, Vol.24, No.1, pp. 15-42, 2011, DOI:10.3970/cmc.2011.024.015

Abstract In this article, explicit transient solutions for one-dimensional wave propagation behavior in multi-layered structures are presented. One of the objectives of this study is to develop an effective analytical method for constructing solutions in multilayered media. Numerical calculations are performed by three methods: the generalized ray method, numerical Laplace inversion method (Durbin's formula), and finite element method (FEM). The analytical result of the generalized ray solution for multilayered structures is composed of a matrix-form Bromwich expansion in the transform domain. Every term represents a group of waves, which are transmitted or reflected through the interface. The matrix representation of the… More >

Chen Y J^1,2, Huber N^2,3

CMC-Computers, Materials & Continua, Vol.16, No.1, pp. 1-24, 2010, DOI:10.3970/cmc.2010.016.001

Abstract An efficient wear integration algorithm is crucial for the simulation of wear in complex transient contact situations. By rewriting Archard's wear law for two dimensional problems, the wear integration can be replaced by the total contact force. This avoids highly resolved simulations in time and space, so that the proposed method allows a significant acceleration of wear simulations. All quantities, including the average contact velocity, slip rate and total contact force, which are required for the pressure-force transformation, can be determined from geometric and motion analysis, or alternatively, from Finite Element simulations. The proposed CForce method has been implemented into… More >

De-Shin Liu¹, Zhen-Wei Zhuang^1,2, Cho-LiangChung³, Ching-Yang Chen⁴

CMC-Computers, Materials & Continua, Vol.13, No.2, pp. 89-114, 2009, DOI:10.3970/cmc.2009.013.089

Abstract This paper employs a novel numerical technique, designated as the hybrid moisture element method (HMEM), to model and analyze moisture diffusion in a heterogeneous epoxy resin containing multiple randomly distributed particles. The HMEM scheme is based on a hybrid moisture element (HME), whose properties are determined by equivalent moisture capacitance and conductance matrixes calculated using the conventional finite element formulation. A coupled HME-FE scheme is developed and implemented using the commercial FEM software ABAQUS. The HME-FE scheme is then employed to analyze the moisture diffusion characteristics of a heterogeneous epoxy resin layer containing particle inclusions. The analysis commences by comparing… More >

I. Smojver¹, J. Sorić²

CMC-Computers, Materials & Continua, Vol.3, No.1, pp. 13-24, 2006, DOI:10.3970/cmc.2007.003.013

Abstract The paper addresses the problem of impact on layered fibre composites. The behaviour of composite laminates under impact loading is dependent not only on the velocity but also on the mass and geometry of the impactor. Using micromechanical Mori-Tanaka approach, mechanical properties of the laminate have been calculated utilizing the material constants of the fibre and matrix. General purpose FEM software ABAQUS has been modified by means of user written subroutines for modelling of composite laminate and rigid impactor. The kinematics of the impact has been simulated using transient dynamic analysis. Employing user defined multi point constraints, delamination zones have… More >