K. Suga, T. Ito

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.4, pp. 99-100, 2011, DOI:10.3970/icces.2011.018.099

Abstract Evaluation and optimization of the multiple-relaxation-time (MRT) lattice Boltzmann method for micro-flows (micro-flow LBM) are performed with the two-dimensional nine discrete velocity (D2Q9) model. The MRT micro-flow LBM consisting of the combination of bounce-back and full diffusive (CBBFD) wall boundary condition is considered. Based on the discussion of Chai et al. (2010), the presently applied CBBFD model and relaxation time for heat flux satisfy the second-order slip boundary condition. However, modification to the MRT model of Chai et al. (MRT-C) is made to the relaxation time for the moments related to the stress by introducing the psi function (Stops,1970; Guo… More >

M. S. Jaafar, J. Noorzaei, A. A. Abdulrazeg, T. A. Mohammed, P.Khanehzaei

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.4, pp. 97-98, 2011, DOI:10.3970/icces.2011.018.097

Abstract Specific features of the thermal stress fields in roller compacted concrete (RCC) dam are always their spatial character and completely dependent on the maturity functions such as deformations properties (elastic, creep). The thermal changes in the material affect the elastic, creep properties of the material, and in turn, the stress fields within the structure. Therefore, the effects of temperature on the properties of RCC materials( elastic, creep) has to be taken into account in order to determine the risk of the thermally induced cracking in these dams. In this study, a viscoelastic model, including ageing effects and thermal dependent properties… More >

Zhanwei Liu, Huimin Xie, Fulong Dai

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 95-96, 2011, DOI:10.3970/icces.2011.018.095

Abstract The mechanical behaviors of microstructures and micro devices have drawn the attention from researchers on materials and mechanics recently. To understand the rule of these behaviors, the deformation measurement techniques with micro/nanometer sensitivity and spatial resolution are required. In this report, a geometric phase analysis technique, SEM scanning moirAC method, digital phase moirAC method based on gratings and a micro-marker identification method are introduced to meet the deformation evaluation requirement of MEMS. The geometric phase analysis technique is performed on the basis of regular gratings, instead of natural atom lattice. The regular gratings with a pitch of range from micrometer… More >

Y. Senda, M. Fujio, S. Shimamura, J. Blomqvist, R. M Nieminen

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 93-94, 2011, DOI:10.3970/icces.2011.018.093

Abstract Atomistic molecular dynamics simulation for"polymer melts has been performed inten-sively and revealed the dynamical behavior of atomistic"chain structure in the melt. These atomistic"calculations, however, have been limited by the massive computational costs because of macroscopic properties of long chain polymer. It would be highly de-sirable to use a multiscale approach covering atomistic and macroscopic behavior of the polymer melt. We have developed computational method coupling atomic model and continuum model [1] and applied the method to polymer melt consisted of the long chain polymers. The polymer molecule is coarse-grained into meso-scopic model by so-called spring- beads model. This spring-beads model… More >

T. Watanabe, T.Gotoh

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 91-92, 2011, DOI:10.3970/icces.2011.018.091

Abstract The effects of polymer additives on decaying isotropic turbulence were numerically investigated using a hybrid approach. The approach consisted of a Brownian dynamics simulation with an enormous number of dumbbells and a turbulence DNS with large-scale parallel computations. A reduction of the energy dissipation rate and modification of the kinetic energy spectrum were observed when the reactions of the polymers were incorporated into the fluid motion. We found that results with few polymers and large replicas could approximate those with many polymers and smaller replicas as far as the large-scale statistics were concerned. More >

Bin GU, LC Zhang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 89-90, 2011, DOI:10.3970/icces.2011.018.089

Abstract Bridging the atomic and continuous analyses is an important aspect in multi-scale mechanics. This paper develops a computational method to integrate the atomic potential of a material with the finite element method. The novelty of this method is that the strain energy is calculated from the atomic potential without the assumption in the Cauchy-Born rule that deformation in a virtual atomic cell is homogeneous. In our new method, the virtual atomic cell deformation is interpolated according to the continuum displacements constructed associated with the shape functions. The applications of the method to single crystal Si and Ge bars under uniaxial… More >

Choong- Han Han, Hei-Sook Nah, Won-Sik Choi, Ki-Beom Ju, Jong-Kwan Song

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 87-88, 2011, DOI:10.3970/icces.2011.018.087

Abstract This study is aimed at improving the safety and maximizing construction productivity by effectively grafting SOC facility construction material to RFID/USN technology for the purpose of science in the maintenance of SOC facility. More >

D. Shaw, W.L. Su

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 85-86, 2011, DOI:10.3970/icces.2011.018.085

Abstract The contact angle affects the life and accuracy of a linear gudieway. In this study, the factors which effect the angle of contact angle of linear guideway includes contact deformation of balls and grooves, downward load, ball diameter, number of load-carrying balls, number of load-carrying rows and conformity. A theoretical approach for finding the contact angle changed of linear gudieway is proposed by using Hertzian theory and Lundeberg/Palmgren approach. The results are useful for modification of loading capability of linear gudieway under load and different preload setting. More >

Cheng Yan, Zhuo-Cheng Oui?a, Zhuo-Ping Duan, Feng-Lei Huang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 83-84, 2011, DOI:10.3970/icces.2011.018.083

Abstract Dynamic behaviors of tensile strength of brittle materials are investigated analytically, and an explicit mathematical expression for the dynamic tensile strength under a quadratic boundary loading is derived, together with the so-called structural-temporal failure criterion. The analytical solution shows reasonably good agreement with the previous dynamic experimental data. Moreover, it is shown by using the explicit expression that the dynamic tensile strength of brittle materials can be determined completely by the quasistatic material parameters such as the quasistatic tensile strength, material density and the incubation-time, which implies that the so-called strain-rate effect on the strength of brittle materials should not… More >

D. Shaw, W.L. Su

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 81-82, 2011, DOI:10.3970/icces.2011.018.081

Abstract Linear rolling ball guideway is a key component of many machines. However, due to the point contact between the ball and the groove, stiffness of linear guideway is the major factor which affects the rigidity and precision of machines. Preload in the guideway can increase the stiffness of linear guideway and thus reduces the position deviation under an external load. The purpose of this study is to develop FEA and compare the results with experimental results to prove the correctness of the FEA model. This model can be used to predict the stiffness of linear guideway with 4 rows of… More >