Dongwoo Sohn¹, Jae Hyuk Lim², Young-Sam Cho³, Seyoung Im¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.10, No.2, pp. 53-54, 2009, DOI:10.3970/icces.2009.010.053

Abstract A novel multiscale finite element (FE) scheme is proposed for a simulation of crack propagation in the heterogeneous media including randomly distributed microstructures, such as voids, rigid fibers. A fine scale mesh is employed to capture the singularity of the crack tip and the effect of microstructures at the vicinity of crack tip. On the other hand, a region far from the crack tip is composed of coarse scale mesh, wherein the effect of the microstructures is averaged through the homogenization theory. An interface between the fine scale mesh and the coarse scale mesh is More >

Ronan Madec¹, Dimitri Komatitsch^1,2, 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 More >

Delfim Soares Jr.¹

CMES-Computer Modeling in Engineering & Sciences, Vol.44, No.2, pp. 157-176, 2009, DOI:10.3970/cmes.2009.044.157

Abstract The numerical modelling of electromagnetic waves by finite element - boundary element coupling procedures is discussed here, taking into account time-domain approaches. In this study, the global model is divided into different sub-domains and each sub-domain is analysed independently and explicitly at each time-step of the analysis: the interaction between the different sub-domains of the global model is accomplished by interface procedures. A multi-level time-step algorithm is considered in order to improve the flexibility, accuracy and stability (especially when conditionally stable time-marching procedures are employed) of the coupled analysis. At the end of the paper, More >

F. Daghia¹, W. Hasan¹, L. Nobile¹, E. Viola^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.39, No.1, pp. 1-28, 2009, DOI:10.3970/cmes.2009.039.001

Abstract In this paper, a finite element model has been developed for analysing the flexural vibrations of a uniform Timoshenko beam-column on a two-parameter elastic foundation. The beam was discretized into a number of finite elements having four degrees of freedom each. The effect of end springs was incorporated in order to identify the end constraints. \newline The procedure for identifying geometric and mechanical parameters as well as the end restraints of a beam on two-parameter elastic foundation is based on experimentally measured natural frequencies from dynamic tests on the structure itself. \newline An iterative statistical More >

G.S. Palani¹, B. Dattaguru², Nagesh R. Iyer¹

Structural Durability & Health Monitoring, Vol.4, No.2, pp. 77-94, 2008, DOI:10.3970/sdhm.2008.004.077

Abstract The objective of this paper is to present a generalized technique called as, numerically integrated Modified Virtual Crack Closure Integral (NI-MVCCI) technique for computation of strain energy release rate (SERR) for 2-D crack problems employing singular finite elements. NI-MVCCI technique is generalized one and the expressions for computing SERR are independent of the finite element employed. Stress intensity factor (SIF) can be computed using the relations between SERR and SIF depending on the assumption of plane stress/strain conditions. NI-MVCCI technique has been demonstrated for 8-noded Serendipity (regular & quarter-point) and 9-noded Lagrangian (regular & quarter-point) More >

F. R. M. Romlay¹

Structural Durability & Health Monitoring, Vol.4, No.1, pp. 19-28, 2008, DOI:10.3970/sdhm.2008.004.019

Abstract This paper presents a surface contact static stress of a spur gear system combined with dynamic characteristic using transient Finite Element Method (FEM). Traditionally, the static stress analysis is done separately with dynamic properties due to limitation of complex equation and avoiding of error occurred. However, in this paper, static stress information is combined with the dynamic mechanism due to the time consuming during the design and analysis stage. A transient FEM analysis is carried out to formulate and solve large systems of algebraic equations in order to obtain a relationship between the contact parameter… More >

O. Oyekoya, D. Mba¹, A. El-Zafrany

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.2, pp. 113-118, 2008, DOI:10.3970/icces.2008.006.113

Abstract In this paper, two new Mindlin-type plate bending elements have been derived for the modelling of functionally graded plate subjected to various loading conditions such as tensile loading, in-plane bending and out-of-plane bending. The properties of the first Mindlin-type element (i.e. Average Mindlin element) are computed by using an average fibre distribution technique which averages the macro-mechanical properties over each element. The properties of the second Mindlin-type element (i.e. Smooth Mindlin element) are computed by using a smooth fibre distribution technique, which directly uses the macro-mechanical properties at Gaussian quadrature points of each element. There More >

Delfim Soares Jr. ¹

CMES-Computer Modeling in Engineering & Sciences, Vol.32, No.2, pp. 57-68, 2008, DOI:10.3970/cmes.2008.032.057

Abstract In this work, a time-domain finite element -- boundary element iterative coupling technique is presented in order to analyse electromagnetic scattering from two-dimensional inhomogeneous objects. In the iterative coupling algorithm, the domain of the original problem is subdivided into sub-domains and each sub-domain is analysed independently (as an uncoupled model) taking into account successive renewals of variables at common interfaces. In order to improve the effectiveness of the iterative coupling approach, the evaluation of an optimised relaxation parameter is discussed, taking into account the minimisation of a square error functional. The algorithm that arises is More >

N.Kringos¹, A.Scarpas¹, A.P.S. Selvadurai²

CMES-Computer Modeling in Engineering & Sciences, Vol.28, No.3, pp. 147-160, 2008, DOI:10.3970/cmes.2008.028.147

Abstract This paper presents a numerical approach for the modeling of water flow induced mastic erosion from a permeable asphalt mix and is part of an ongoing effort to model moisture-induced damage in asphalt mixes. Due to the complex composite structure of asphalt mixtures, moisture can infiltrate in various ways into the components and have an adverse effect on its mechanical performance. Depending on the gradation of the asphalt aggregates and the mixing procedure, asphalt structures with a variable permeability may result. Open-graded asphalt mixes are designed with a high interconnected air void content to serve More >

A. Cazzani¹, E. Garusi², A. Tralli³, S.N. Atluri⁴

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.2, pp. 93-122, 2007, DOI:10.3970/icces.2007.004.093

Abstract Fibre-reinforced plates and shells are finding an increasing interest in engineering applications. Consequently, efficient and robust computational tools are required for the analysis of such structural models. As a matter of fact, a large amount of laminate finite elements have been developed and incorporated in most commercial codes for structural analysis. In this paper a new laminate hybrid assumed-strain plate element is derived within the framework of the First-order Shear Deformation Theory (i.e. assuming that particles of the plate originally lying along a straight line which is normal to the undeformed middle surface remain aligned… More >