A.Oba¹, Y.Fujii², M.Okuma³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.1, pp. 51-56, 2008, DOI:10.3970/icces.2008.007.051

Abstract In this paper, the authors present a new evolutionary structural optimization method based on FE modeling using identical cubic elements for optimizing strength and dynamics characteristics of structures. The method is developed from the previous ones([1\hbox {}]-[3\hbox {}]), and carries out the size and topological shape optimization to satify the strength against external force and inertia force of itself and to control the natural frequencies of the structure. The method gives us the lightest structure satisfying the requirement about the strength and dynamic characteristics. The outline of the method is presented first, and a basic case study about a bridge… More >

Peng Ni¹, Homer Walker¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.1, pp. 43-50, 2008, DOI:10.3970/icces.2008.007.043

Abstract One of the fundamental problems in electronic structure calculations is to determine the electron density associated with the minimum total energy of a molecular or bulk system. The total energy minimization problem is often formulated as a nonlinear eigenvalue problem. The most widely used algorithm for solving this type of problem is the self-consistent field (SCF) iteration accelerated by Direct Inversion on the Iterative Subspace (SCF-DIIS), in which a linearly constrained least-squares problem is embedded. We will examine and compare the numerical stability of three different ways to solve this least-squares problem. More >

Iizuka Yoichiro¹, Hiroshi Yamaura

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.1, pp. 23-42, 2008, DOI:10.3970/icces.2008.007.023

Abstract Crown rollers are often used in the flexible media transport mechanism consists of a rubber layered roller and a steel roller. In this paper, the flexible media transport characteristics of crown roller is investigated theoretically. The purpose of this study is to analyze the flexible media transport characteristics such as longitudinal distribution of nip pressure, traction and transport velocity and so on, and to develop the design method of crown roller that has desired characteristics. More >

Y. Adachi¹, F. Sako¹, S. Qinzhong², S. Ando², M. Tsuchihashi², I. Hagiwara³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.1, pp. 19-22, 2008, DOI:10.3970/icces.2008.007.019

Abstract In this paper, the vibration response of the satellite equipment panel during the launch phase is predicted in consideration of the robustness. By using a simplified model consisted of a panel and an acoustic cavity, Monte Carlo simulation in which analytical parameters are changed at random in the conceivable range of variation is done. From the result, the acceleration power spectral density (PSD) of the satellite equipment panel is obtained. After statistical processing, the effect of variation on the vibration response is estimated and the proper design criteria of the equipment are defined. More >

B. J. Henz¹, D. R. Shires²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.1, pp. 13-18, 2008, DOI:10.3970/icces.2008.007.013

Abstract The capability to predict the residual stresses induced during the manufacturing process in composite components is necessary for the timely fielding of new combat systems. At the U.S. Army Research Laboratory we have developed a computational environment to model the resin flow, heat transfer, curing, and residual stresses in composite components manufactured with the resin transfer molding (RTM) process. This computational environment uses object-oriented programming methods to provide model coupling capabilities and access to high performance computing assets. In this paper we will provide details of the physical models, software, and the validation/verification procedure used to develop this RTM simulation… More >

K.K. Kratmann^1,3, M.P.F. Sutcliffe², L.T. Lilleheden³, O.T. Thomsen¹, R. Pyrz¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.1, pp. 7-12, 2008, DOI:10.3970/icces.2008.007.007

Abstract This paper concerns the quantification of fibre misalignment in unidirectional carbon fibre reinforced polymer composites (UD CFRP). The motivation for determining the fibre misalignment is described and existing applicable methods are presented. The concept of a newly developed image analysis procedure is described and the test procedures used to verify the robustness and precision of the method are presented along with selected results. More >

K. Yamamoto¹, M. Tanaka¹, S. Tashiro¹, K. Nakata¹, K. Yamazaki², E. Yamamoto², K. Suzuki², A. B. Murphy³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.1, pp. 1-6, 2008, DOI:10.3970/icces.2008.007.001

Abstract Authors have used a numerical model of stationary helium TIG arc welding taking into account the iron, chromium and manganese vapors produced from the weld pool surface and have simulated the distribution of the metal vapors, plasma temperature, fluid flow velocity and the formation of the weld pool. The concentration of manganese vapor in arc plasma was much higher compared with the composition of manganese for stainless steel. More >

C. Janna¹, M. Ferronato¹, G. Gambolati¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.4, pp. 239-244, 2008, DOI:10.3970/icces.2008.006.239

Abstract The geomechanical simulation of a faulted producing reservoir is a strongly non-linear problem due to the non-elastic behaviour of the depleted rocks and especially to the contact constraint prescribed on the fault surfaces. With penalty interface elements for the fault modeling the stiffness matrix may be severely ill-conditioned and the solution by the Preconditioned Conjugate Gradient requires the development and the implementation of ad hoc preconditioners. The present communication investigates the performance of a multilevel incomplete factorization aimed at enhancing convergence and reducing the computational cost of a non-linear geomechanical simulation. More >

M. Baldinger¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.4, pp. 233-238, 2008, DOI:10.3970/icces.2008.006.233

Abstract The aim of this paper is to demonstrate how the new highest technology can be used to develop and optimize the manufacturing plant. Based on the results of a preliminary study and other observations made during the last year, it was decided to bring a new technology in its factory. On the basis of climbing demand and the ever bigger nascent variety with the production of self loading wagons, the machine-factory is modernized by a mounting-street for self loading wagons. The use of RFID-technology, tied into an ERP-System, led to a clear optimization of the production-process. More >

SAKO Fumiko¹, ADACHI Yukihiro¹, SHI Qinzhong², ANDO Shigemasa², TSUCHIHASHI Masahiro², HAGIWARA Ichiro³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.4, pp. 229-232, 2008, DOI:10.3970/icces.2008.006.229

Abstract Satellite equipment experience severe high random acoustic loads during launch phase. [1\hbox {}] Accurate prediction of this random vibration is demanded to prevent equipmtnt from trouble. In this paper, a new approach for vibro-acoustic coupling analysis is proposed to obtain more accurate prediction. The proposed method applies Mechanical Impedance Method to vibro-acoustic coupling analysis with FEM model of structure and SEA model of sound system. \newline The analysis of simple model is conducted to study the proposed method. The result from the comparison shows this method provides more accurate prediction with structure impedance calculated from area-excitation analysis than from point-excitation… More >