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T. Ishikawa¹, H. Fujiwara¹, N. Matsuki², R. Lima³, Y. Imai¹, T. Yamaguchi²
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 77-78, 2009, DOI:10.3970/icces.2009.009.077
Abstract In a small artery, the blood is no longer assumed as a homogeneous fluid, because the size of blood cells cannot be neglected compared to the generated flow field. In such a case, we need to treat the blood as a multi-phase fluid, and investigate the motion of individual cells in discussing the flow field. Blood may be modelled as a suspension of red blood cells (RBCs) in plasma, because about 99% of volume fraction of blood cells is RBCs.
In order to measure a blood flow experimentally, various methods have been employed. However, most of conventional techniques are difficult… More >

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886

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T. Yamaguchi¹, T. Ishikawa², Y. Imai²
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 79-80, 2009, DOI:10.3970/icces.2009.009.079
Abstract Human cardiovascular system is always under the integrated nervous and humoral control of the whole body, i.e. in homeostasis. Multiple feedback mechanisms with mutual interactions among systems, organs, and even tissues provide integrated control of the entire body. These control mechanisms have different spatial coverages, from the micro- to macroscale, and different time constants, from nanoseconds to decades. We think that these variations in spatial as well as temporal scales should be taken into account in discussing phenomena in the cardiovascular system.
In this background,we have been investigatingthe cardiovascular system over micro to macro levels by using conjugated computational mechanics… More >

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878

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Chun-Lang Yeh¹
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 81-94, 2009, DOI:10.3970/icces.2009.009.081
Abstract In this study, the vaporization process of a nanojet is investigated by molecular dynamics simulation. Liquid argon nanojet made of 44000 Lennard-Jones molecules is investigated under various simulation parameters to examine their influence on the nanojet vaporization process. Snapshots of the molecules, evolution of the density field, and evolution of the intermolecular force are analyzed. The present simulation results can provide insight into the fundamental mechanism of the atomization process and will be helpful for the design of nanojet devices such as nano-printer or nano-sprayer. More >

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825

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H. T. Wang¹, Z. H. Yao²
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 95-96, 2009, DOI:10.3970/icces.2009.009.095
Abstract Carbon nanotubes (CNTs) may provide ultimate enhancement in stiffness and str\discretionary {-}{}{}ength for composite materials. This paper presents a rigid-fiber-based boundary integral equation formulation for the numerical simulation of debonding process and the corresponding strength of CNT reinforced composites. The CNT/matrix interfaces are assumed to fail when the interfacial shear force reaches a prescribed threshold, and the CNTs and matrix are considered to be detached in the failed areas. The matrix with one or several tens of originally well-bonded CNTs is subjected to an incremental tensile load and the effective stress-strain relations are readily obtained by the introduction of CNT/matrix… More >

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884

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Nabeel Z. Al-Rawahi¹
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 97-98, 2009, DOI:10.3970/icces.2009.009.097
Abstract Due to the complexity of multi-phase flow (MPF) phenomena research in this area is largely based on experimentation using laboratory scale test loops. The design of multi-phase flow test facilities is quite involved and requires careful attention. First, the test rigs have to produce results that are valid or can be scaled to actual full scale systems. This demands that the system geometry and dimensions, the flow drivers (pumps and compressors), flow controls (flow meters, pressure regulators, etc.) and the flow measurement sensors (pressure, temperature, velocity, ..etc) have to be selected so that a wide range of flow conditions can… More >

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1320

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G. Gambolati¹, M. Ferronato¹, C. Janna¹
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 99-106, 2009, DOI:10.3970/icces.2009.009.099
Abstract The Finite Element (FE) solution to consolidation equations in large geological settings raises a few numerical issues depending on the actual process addressed by the analysis. There are two basic problems where the solver efficiency plays a crucial role: 1- fully coupled consolidation, and 2- non-linear faulted (uncoupled) consolidation. Using a proper nodal numbering the FE matrices exhibit a block (or multilevel) structure. Krylov subspace solvers are attracting a growing attention, provided that a relatively inexpensive and effective preconditioner is available. For both problems possible preconditioners include the Diagonal Scaling (DS), the Incomplete Triangular Factorization (ILU), the Mixed Constraint Preconditioning… More >

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844

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Cheng-Hung Huang^1,2, Hsin-Hsien Wu¹
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 107-108, 2009, DOI:10.3970/icces.2009.009.107
Abstract The conjugate gradient method (CGM) is applied in an inverse fin design problem in estimating the optimum shapes for the non-Fourier spine and longitudinal fins based on the desired fin efficiency and fin volume at the specified time. One of the advantages in using CGM in the inverse design problem lies in that it can handle problems having a huge number of design parameters easily and converges very fast.
The validity of using CGM in solving the present inverse design problem is justified by performing the numerical experiments. Several test cases involving different design fin efficiency, design fin volume, specified… More >

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833

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S. Ozaki¹, D.H. Chen²
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 109-116, 2009, DOI:10.3970/icces.2009.009.109
Abstract In the present study, the collapse behavior of a thin-plate subjected to axial compression is investigated parametrically using the finite element method. It is revealed that the axial collapse of the plate, which has various hardening characteristics, is induced by two dominant factors: the stress limitation of the material and the limitation of in-plane deformation at the side edges of the plate. Then, a simplified collapse condition, which corresponds to two modes, is derived based on the plastic buckling theory and the effective width concept, and the validity of the simplified collapse condition is then verified by the comparison of… More >

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857

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Xia Yuan¹, Wu Jichun², Zhou Luying³
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 117-126, 2009, DOI:10.3970/icces.2009.009.117
Abstract This paper establishes a difference approximation on time-space fractional advection-dispersion equations. Based on the difference approximation an ideal numerical example has been solved, and the result is compared with the one of the rigorous time fractional advection-dispersion equation and the rigorous space fractional advection-dispersion equation respectively. The results show: when time fractional order parameter γ=1 or space fractional order parameter α=2, the numerical calculation result of the time-space fractional advection-dispersion equations is in accordance with that of the rigorous time fractional advection-dispersion equation or the rigorous space fractional advection-dispersion equation. The variation law of the result with parameter is also… More >

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872

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Harald Berger¹, Ulrich Gabbert², Reinaldo Rodriguez-Ramos³
The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 127-129, 2009, DOI:10.3970/icces.2009.009.127
Abstract Piezoelectric materials have the property of converting electrical energy into mechanical energy and vice versa. This reciprocity in the energy conversion makes piezoelectric ceramics very attractive for use as sensors and actuators. By combining piezoelectric fibers with passive non-piezoelectric polymer composites with superior properties can be created. But for design of such smart micro-macro structures homogenization techniques are necessary to describe the overall behavior of piezocomposites expressed by effective material coefficients.
A number o fnumerical and analytical methods have been developed to estimate the effective coefficients. Although analytical homogenization methods provide excellent results it is difficult to extend them to… More >

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817