V.C. Santos¹, P.S. Lopes¹, R. Gärtner², A.B. Jorge¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.2, pp. 53-58, 2007, DOI:10.3970/icces.2007.004.053

Abstract This work presents an approach for weight and reliability optimization of aeronautical armors. Military and police helicopters are usually exposed to highly risky situations, with a high probability for these aircrafts to be hit by projectiles. In this context, floor aircraft armor can be used to protect the crews' lives. However, the armoring of an aircraft causes an increase in weight. If this extra weight is poorly arranged, the changes in aircraft centroid position may even destabilize the aircraft. Thus, it is essential to design an armor not only to protect the aircraft, but also… More >

Ronald D. Kriz¹, Arun K. Nair²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.3, No.1, pp. 43-50, 2007, DOI:10.3970/icces.2007.003.043

Abstract This article has no abstract. More >

Biyue Liu¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.1, pp. 35-40, 2007, DOI:10.3970/icces.2007.001.035

Abstract It is well known that the Reynolds number has a significant effect on the blood flow in human arteries. We developed a three dimensional model with simplified geometry for a diseased right coronary artery segment to study the influence of the Reynolds number on the flow pattern in a stenotic coronary artery. Computations were carried out under physiological flow conditions to examine how the characteristics of the flow, such as the flow velocity and the pressure drop along the inner wall, change corresponding to the varying of the blood viscosity or to the varying of More >

Nishioka T.¹, Fujita N.¹, Fujimoto T.¹, Kogame M.¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.3, pp. 127-132, 2007, DOI:10.3970/icces.2007.001.127

Abstract In this study, numerical simulations of mixed-mode fracture paths in dynamic fracture phenomenon are carried out by using moving finite element method based on Delaunay automatic mesh generation. In addition, the experiments under same condition was carried out, and the both results were compared. The calculated paths by the simulation agree well with the fracture paths of the experiments. More >

Dalin Tang^*, Chun Yang^†, Tal Geva^‡,§, Pedro J. del Nido^¶

Molecular & Cellular Biomechanics, Vol.4, No.3, pp. 159-176, 2007, DOI:10.3970/mcb.2007.004.159

Abstract A single-layer isotropic patient-specific right/left ventricle and patch (RV/LV/Patch) combination model with fluid-structure interactions (FSI) was introduced in our previous papers to evaluate and optimize human pulmonary valve replacement/insertion (PVR) surgical procedure and patch design. In this paper, an active anisotropic model with two-layer structure for ventricle wall and tissue fiber orientation was introduced to improve previous isotropic model for more accurate assessment of RV function and potential application in PVR surgery and patch design. A material-stiffening approach was used to model active heart contraction. The computational models were used to conduct ``virtual (computational)'' surgeries More >

I.S. Raju¹, E.H. Glaessgen¹, B.H. Mason¹, T. Krishnamurthy¹, C.G. Davila¹

CMES-Computer Modeling in Engineering & Sciences, Vol.22, No.1, pp. 1-30, 2007, DOI:10.3970/cmes.2007.022.001

Abstract A detailed finite element analysis of the right rear lug of the American Airlines Flight 587 - Airbus A300-600R was performed as part of the National Transportation Safety Board's failure investigation of the accident that occurred on November 12, 2001. The loads experienced by the right rear lug were evaluated using global models of the vertical tail, local models near the right rear lug, and a global-local analysis procedure. The right rear lug was analyzed using two modeling approaches. In the first approach, solid-shell type modeling was used, and in the second approach, layered-shell type… More >

J. Perko¹, B. Šarler²

CMES-Computer Modeling in Engineering & Sciences, Vol.19, No.1, pp. 55-68, 2007, DOI:10.3970/cmes.2007.019.055

Abstract This work introduces a procedure for automated determination of weight function free parameters in moving least squares (MLS) based meshless methods for non-uniform grids. The meshless method used in present work is Diffuse Approximate Method (DAM). The DAM is structured in 2D with the one or two parameter Gaussian weigh function, 6 polynomial basis and 9 noded domain of influence. The procedure consists of three main elements. The first is definition of the reference quality function which measures the difference between the MLS approximation on non-uniform and hypothetic uniform node arrangements. The second is the… More >

L. Lamberti^1,2, C. Pappalettere^1,3

CMES-Computer Modeling in Engineering & Sciences, Vol.18, No.3, pp. 183-222, 2007, DOI:10.3970/cmes.2007.018.183

Abstract This paper presents a novel optimization algorithm for minimizing weight of skeletal structures. The algorithm--denoted as MPISA (Multi Point Improved Simulated Annealing)--utilizes a multi-level simulated annealing scheme where different candidate designs are compared simultaneously. This is done in purpose to increase computational efficiency and to minimize the number of exact structural analyses.
MPISA is tested in three complicated design problems of skeletal structures: (i) sizing optimization of a planar bar truss under five independent loading conditions including 200 design variables; (ii) sizing-configuration optimization of a cantilevered bar truss including 81 design variables; (iii) sizing-configuration optimization More >

Chun-Ying. Wu¹, R. Al-Khoury², C. Kasbergen², Xue-Yan. Liu², A. Scarpas²

CMES-Computer Modeling in Engineering & Sciences, Vol.17, No.3, pp. 163-172, 2007, DOI:10.3970/cmes.2007.017.163

Abstract 3D spectral element method in the article is presented to predict the pavement layer modules using field measurement of Falling Weight Deflectometer (FWD). To improve the computational efficiency of the layer-condition assessment, one type of spectral element is proposed to develop the dynamic analysis of 3D multi-layered system subjected to an impulsive load. Each layer in structure is simulated as two-noded layer spectral element or one-noded spectral element in frequency domain. In order to identify the parameters of layered structures, a nonlinear optimization method called Powell hybrid algorithm is employed. The optimization procedure is performed More >

S. K. Panthi^1,2, N. Ramakrishnan², K. K. Pathak², J. S. Chouhan³

CMC-Computers, Materials & Continua, Vol.6, No.1, pp. 13-20, 2007, DOI:10.3970/cmc.2007.006.013

Abstract One of the important features of flanging process is elastic recovery during unloading leading to springback. The elastic recovery is associated with various tool and material parameters. It is difficult to analytically predict the elastic recovery accurately owing to the complex material deformation behavior. In this investigation, a commercially available Finite Element software is used for elasto-plastic analysis of flanging process. The springback is studied varying geometrical, material and friction parameters. The results of the simulation are validated with a few published experimental results. More >