Cheng Wang¹, Jianguo Ning¹, Tianbao Ma¹

CMC-Computers, Materials & Continua, Vol.22, No.1, pp. 73-96, 2011, DOI:10.3970/cmc.2011.022.073

Abstract In this paper, we report high resolution simulations using a fifth-order weighted essentially non-oscillatory (WENO) scheme with a third-order TVD Runge-Kutta time stepping method to examine the features of the detonation for gas and condensed explosives. A two-stage chemical reaction model and an ignition and growth model are employed to describe the chemical reaction process for gas and condensed explosives. Based on the Steger-Warming vector flux splitting method, a splitting method is employed when the vector flux does not satisfy the homogeneity property for simulating detonation wave propagation for condensed explosives. The sensibility of flame propagation process and explosion overpressure… More >

Smitha Gopinath^1,2, A. Ramach,ra Murthy¹, Nagesh R. Iyer¹

CMC-Computers, Materials & Continua, Vol.22, No.1, pp. 55-72, 2011, DOI:10.3970/cmc.2011.022.055

Abstract This paper presents the mathematical modeling techniques for nonlinear finite element analysis of RC structure to incorporate uniform corrosion effects. Effect of corrosion has been simulated as reduction in effective cross-sectional area of reinforcing bar, reduction in bonding phenomena and as reduction in material properties of reinforcing bar such as yield strength and elastic modulus. Appropriate constitutive laws for (i) corroded rebar elements and (ii) bond slip with corroded bar have been described. Procedure has been outlined to determine the global damage indicator by secant stiffness based approach. A corroded RC beam has been analysed to validate the proposed model… More >

Zhao Huiming¹, Dong Zhengzhu¹, Chen Jiarui¹, Yang Min¹

CMC-Computers, Materials & Continua, Vol.21, No.3, pp. 209-216, 2011, DOI:10.3970/cmc.2011.021.209

Abstract The advantages of coupling of a natural boundary element method and a finite element method are introduced. Then we discuss the principle of the direct coupling of NBEM and FEM and its implementation. The comparison of the results between the direct coupling method and FEM proves that the direct coupling method is simple, feasible and valid in practice. More >

Zhuo-Jia Fu^1,2, Wen Chen¹, Qing-Hua Qin^2,3

CMC-Computers, Materials & Continua, Vol.21, No.3, pp. 187-208, 2011, DOI:10.3970/cmc.2011.021.187

Abstract This paper presents a hybrid finite element model (FEM) with a new type of general solution as interior trial functions, named as HGS-FEM. A variational functional corresponding to the proposed general solution is then constructed for deriving the element stiffness matrix of the proposed element model and the corresponding existence of extremum is verified. Then the assumed intra-element potential field is constructed by a linear combination of novel general solutions at the points on the element boundary under consideration. Furthermore, the independent frame field is introduced to guarantee the intra-element continuity. The present scheme inherits the advantages of hybrid Trefftz… More >

Surkay D. Akbarov^1,2, Resat Kosker³, Nihan T. Cinar³

CMC-Computers, Materials & Continua, Vol.21, No.2, pp. 119-146, 2011, DOI:10.3970/cmc.2011.021.119

Abstract In the present paper, the stress distribution in an infinite elastic body containing two neighboring nanofibers is studied. It is assumed that the midlines of the fibers are in the same plane. With respect to the location of the fibers according to each other the co-phase and anti-phase curving cases are considered. At infinity uniformly distributed normal forces act in the direction of the nanofibers, location. The investigations are carried out in the framework of the piecewise homogeneous body model with the use of the three-dimensional geometrically non-linear exact equations of the theory of elasticity. The normal and shear self-equilibrated… More >

Chih-Wen Chang¹

CMC-Computers, Materials & Continua, Vol.21, No.2, pp. 87-106, 2011, DOI:10.3970/cmc.2011.021.087

Abstract We address a new numerical approach to deal with these multi-dimensional backward wave problems (BWPs) in this study. A fictitious time τ is utilized to transform the dependent variable u(x, y, z, t) into a new one by (1+τ)u(x, y, z, t)=: v(x, y, z, t, τ), such that the original wave equation is written as a new hyperbolic type partial differential equation in the space of (x, y, z, t, τ). Besides, a fictitious viscous damping coefficient can be employed to strengthen the stability of numerical integration of the discretized equations by using a group preserving scheme. Several numerical… More >

Tian-Zhong Wang¹, You-He Zhou^1,2

CMC-Computers, Materials & Continua, Vol.21, No.1, pp. 41-64, 2011, DOI:10.3970/cmc.2011.021.041

Abstract Based on the thermodynamic theory and the postulates of Jiles and Atherton, a general coupled magnetic-elastic-thermal free-energy model with hysteretic nonlinearity is established for Terfenol-D rods, in which the effect of Weiss molecular field is incorporated. The quantitative agreement between numerical simulation results predicted by the free-energy model and existing experimental data confirms the validity and reliability of the obtained nonlinear theoretical model, and indicates that the free-energy model can accurately capture the nonlinear hysteresis characteristic of Terfenol-D. Meanwhile, the free-energy model is employed to investigate the influences of mechanical stress and the temperature on the magnetostrictive effect of Terfenol-D… More >

Chein-Shan Liu¹

CMC-Computers, Materials & Continua, Vol.21, No.1, pp. 17-40, 2011, DOI:10.3970/cmc.2011.021.017

Abstract Only the left-boundary data of temperature and heat flux are used to estimate an unknown parameter function α(x) in T_t(x,t) = ∂(α(x)T_x)/∂x + h(x,t), as well as to recover the right-boundary data. When α(x) is given the above problem is a well-known inverse heat conduction problem (IHCP). This paper solves a mixed-type inverse problem as a combination of the IHCP and the problem of parameter identification, without needing to assume a function form of α(x) a priori, and without measuring extra data as those used by other methods. We use the one-step Lie-Group Adaptive Method (LGAM) for the semi-discretizations of… More >

G. Gang¹, Y.H. Liu²

CMC-Computers, Materials & Continua, Vol.20, No.3, pp. 251-272, 2010, DOI:10.3970/cmc.2010.020.251

Abstract Limit and shakedown analysis theorems are the theories of classical plasticity for the direct computation of the load-carrying capacity under proportional and varying loads. Based on Melan's theorem, a solution procedure for lower bound limit and shakedown analysis of three-dimensional (3D) structures is established making use of the finite element method (FEM). The self-equilibrium stress fields are expressed by linear combination of several basic self-equilibrium stress fields with parameters to be determined. These basic self-equilibrium stress fields are elastic responses of the body to imposed permanent strains obtained through elastic-plastic incremental analysis by the three-dimensional finite element method (3D-FEM). The… More >

X. H. Du¹, X. P. Shen¹

CMC-Computers, Materials & Continua, Vol.20, No.3, pp. 225-242, 2010, DOI:10.3970/cmc.2010.020.225

Abstract Aim of this paper is to estimate the integrity of liquefied natural gas (LNG) prestressed storage tank under seismic influence. The coupled Eulerian-Lagrangian (CEL) analysis technique is used to simulate the fluid-structure interaction between LNG and the cylinder of LNG prestressed storage tank. The 3-D model of LNG has been dispersed by Eulerian mesh that is different from traditional analysis method which is called the added mass method. Meanwhile, both of the 3-D models of prestressed rebar and concrete structure are dispersed by Lagrangian mesh. Following conclusions are obtained: 1) Natural frequency of the whole model has been obtained by… More >