H. Ghasemnejad¹, H. Hadavinia^1,2, D. Marchant¹, A. Aboutorabi¹

Structural Durability & Health Monitoring, Vol.4, No.1, pp. 29-46, 2008, DOI:10.3970/sdhm.2008.004.029

Abstract In this paper the crashworthiness capabilities of thin-walled corrugated crash boxes in axial crushing relative to flat sidewall boxes from the same material are investigated. In order to achieve this, various design of corrugated aluminium alloy 6060 temper T4 crash boxes were chosen and their axial crushing behaviour under impact loading was studied by developing a theoretical model based on Super Folding Element theory and by conducting finite element analysis using LS-DYNA in ANSYS. From the theoretical and FE analysis the crush force efficiency, the specific energy absorption and the frequency and amplitude of fluctuation of More >

Shueei-Muh Lin^1,3, Sen-Yung Lee², Cheng-Chuan Tsai², Chien-Wi Chen²,Wen-Rong Wang³, Jenn-Fa Lee³

CMES-Computer Modeling in Engineering & Sciences, Vol.34, No.1, pp. 33-54, 2008, DOI:10.3970/cmes.2008.034.033

Abstract The conventional theories for circulation of arteries are emphasized on fluid behavior or some simplified models for experimental utility. In this study, a new mathematical theory is proposed to describe the wave propagation through the elastic tube filled with viscous and incompressible fluid. The radial, longitudinal and flexural vibrations of a tube wall are introduced simultaneously. Meanwhile, the linearlized momentum and continuity equations of tube flow field are expressed in the integral form. Based on these considerations, three wave modes are obtained simultaneously. These wave modes are the flexural, Young and Lamb modes, respectively. The… More >

E. Pan^1,2, Y. Zhang², P. W. Chung³, M. Denda⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.24, No.2&3, pp. 157-168, 2008, DOI:10.3970/cmes.2008.024.157

Abstract Quantum-dot (QD) semiconductor synthesis is one of the most actively investigated fields in strain energy band engineering. The induced strain fields influence ordering and alignment, and the subsequent surface formations determine the energy bandgap of the device. The effect of the strains on the surface formations is computationally expensive to simulate, thus analytical solutions to the QD-induced strain fields are very appealing and useful. In this paper we present an analytical method for calculating the QD-induced elastic field in anisotropic half-space semiconductor substrates. The QD is assumed to be of any polyhedral shape, and its… More >

S. Sabbaghi¹, M. Shariaty-Niassar², Sh. Ayatollahi¹, A. Jahanmiri¹

FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.2, pp. 113-124, 2008, DOI:10.3970/fdmp.2008.004.113

Abstract In this study, the Onset of Asphaltene Precipitation is predicted by a modified Virial equation of state. The bases of quantum mechanics and statistical thermodynamics are used to evaluate the potential energy and intermolecular forces related to asphaltene molecules. The Virial equation of state is modified using group-contribution-methods for asphaltenes, which are assumed to be polymeric-like compounds consisting of aggregates of monodisperse asphaltene monomers. It is shown how the modified Virial equation of state with the Peneloux correction leads to estimate the molar volume and solubility parameter. These parameters are also compared successfully with results More >

M. Daian¹, A. Taube², G. Torgovnikov³, G. Daian⁴, Y. Shramkov⁵

CMC-Computers, Materials & Continua, Vol.8, No.3, pp. 165-172, 2008, DOI:10.3970/cmc.2008.008.165

Abstract Microwave wood modification and treatment technologies become more and more essential within the wood industry due to their technical and economical advantages. Microwave processing of wood involves many complicated physical phenomena and requires a very careful control of variables (such as intensity of microwave power, loading period, maximum temperature, etc.) in order to reduce structural deformations of the processed wood. To optimise and minimise the project design engineers' work, modelling and simulation of the microwave energy-wood interaction represents an indispensable tool.
This research work has been undertaken with the aim to design and optimise microwave… More >

P.H. Wen¹, M.H. Aliabadi²

Structural Durability & Health Monitoring, Vol.3, No.2, pp. 107-120, 2007, DOI:10.3970/sdhm.2007.003.107

Abstract In the last decade, meshless methods for solving differential equations have become a promising alternative to the finite element and boundary element methods. Based on the variation of potential energy, the element-free Galerkin method is developed on the basis of finite element method by the use of radial basis function interpolation. An enriched radial basis function is formulated to capture the stress singularity at the crack tip. The usual advantages of finite element method are retained in this method but now significant improvement of accuracy. Neither the connectivity of mesh in the domain by the More >

J. Mohan¹, D. Carolan¹, N. Murphy¹, A. Ivankovic¹, D. Dowling¹

Structural Durability & Health Monitoring, Vol.3, No.2, pp. 81-86, 2007, DOI:10.3970/sdhm.2007.003.081

Abstract The aim of this work is to investigate the influence of a variety of plasma treatments on the surface properties of an epoxy-based composite material and to establish a relationship between these properties and the subsequent mechanical behaviour of adhesively bonded joints. To this end, specimens were subjected to three different types of plasma treatment: two short treatments (2min) of He and He plus O₂, and one long treatment (15min) of He plus O₂. The variation in surface energy of the composite specimens was examined in each case over a period of up to 3 days… More >

C.P. Providakis¹

Structural Durability & Health Monitoring, Vol.3, No.1, pp. 29-34, 2007, DOI:10.3970/sdhm.2007.003.029

Abstract Actuators are structures that give micro-electro-mechanical systems (MEMS) the ability to interact with their environment rather than just passively sensing it. Recent studies of MEMS thermal micro-actuators have shown that simple in design and production devices can provide deflection of the order of 10 μm at low voltages. Recently, metals and single-crystal silicon materials were included in the range of materials used for thermal actuators since they operate at lower temperatures than the commonly used (poly)silicon devices. These actuators are liable to meet the loads in service, so the corresponding integrity and stability analysis constitutes a… More >

N. Ohno¹, D. Okumura¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.4, pp. 207-214, 2007, DOI:10.3970/icces.2007.004.207

Abstract The self energy of geometrically necessary dislocations (GNDs) is considered to inevitably introduce the higher-order stress work-conjugate to slip gradient in single crystals. It is pointed out that this higher-order stress stepwise changes in response to in-plane slip gradient and thus directly influences the onset of initial yielding in polycrystals. The self energy of GNDs is then incorporated into the strain gradient theory of Gurtin (2002). The resulting theory is applied to model crystal grains of size D, leading to a D-1-dependent term with a coefficient determined by grain shape and orientation. It is thus More >

K. Gordnian¹, H. Hadavinia¹, G. Simpson¹, A. Aboutorabi¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.2, pp. 61-68, 2007, DOI:10.3970/icces.2007.001.061

Abstract The compliance equation is used to calculate the energy release rate for angle ply laminated double cantilever composite beam specimen. Instead of the traditional approach of a beam on an elastic foundation, a second order shear thickness deformation beam theory (SSTDBT) has been considered. More >