Myung Jo Jhung, Yong Ho Ryu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.2, pp. 39-40, 2011, DOI:10.3970/icces.2011.016.039

Abstract Korea is developing one of advanced small and medium-sized reactor called SMART (System-integrated Modular Advanced ReacTor), an integral type pressurized water reactor with the thermal power of 330 MW, by combining innovative safety features and its own indigenous technologies with proven light water reactor technologies. The reactor assembly of SMART contains major primary systems such as fuel and core, 8 steam generators, a pressurizer, 4 main coolant pumps, and 25 control rod drive mechanisms in a single pressurized reactor vessel. The integrated arrangement of these components enables the removal of the large size pipe connections between major components of reactor… More >

Xiaoyang LU, Bingtao TANG

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.2, pp. 37-38, 2011, DOI:10.3970/icces.2011.016.037

Abstract Bending movements will be caused when elements passing by die entrance radius. The classical inverse analysis method (CIAM) uses the constitutive equation based on deformation theory of plasticity. Based on the assumption of the proportional loading, Hencky deformation theory is adopted. The secant modulus is obtained from uniaxial tensile curve and the plastic strain rate can be directly integrated to obtain a total plastic strain expression. The CIAM of sheet metal stamping has the shortcomings of no consideration of the effects of deformation history on stress prediction. Therefore, there is some discrepancy between the stress calculated with CIAM and that… More >

Haofeng Chen

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.2, pp. 35-36, 2011, DOI:10.3970/icces.2011.016.035

Abstract In this paper a state-of-the-art numerical method is discussed for the evaluation of the shakedown and ratchet limits for an elastic-perfectly plastic body subjected to cyclic thermal and mechanical load history. The limit load, i.e. the load carrying capacity, is also determined as a special case of shakedown analysis. These design limits in plasticity have been solved by characterising the steady cyclic state using a general cyclic minimum theorem. For a prescribed class of kinematically admissible inelastic strain rate histories, the minimum of the functional for these design limits are found by a programming method, the Linear Matching Method (LMM),… More >

Yang Cheng, Bin Jia, Ming Xin

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.2, pp. 33-34, 2011, DOI:10.3970/icces.2011.016.033

Abstract A sparse grid approach to orbit uncertainty propagation is presented. Efficient and accurate uncertainty propagation methods for nonlinear dynamic systems have been of enormous interest to space object tracking. Recent methods include those based on the time evolution of the probability density function, the statistical moments, the random samples, or a sum of Gaussian components. The idea of the sparse grid method for orbit uncertainty propagation is to represent the initial uncertainty by a sparse grid, propagate the sparse grid points individually through the nonlinear orbit dynamics, and compute the statistical moments from the propagated sparse grid points. The Smolyak… More >

Y.C. Shiah, C.L. Tan

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.1, pp. 31-32, 2011, DOI:10.3970/icces.2011.016.031

Abstract In the boundary element method (BEM), interior point solutions for the displacements and the stresses at an interior point of an elastic body are obtained through the numerical evaluation of the Somigliana's identities. It is carried out as a secondary exercise in the BEM analysis, after the boundary integral equation (BIE) has been solved for all the unknown displacements and tractions on the surface of the domain. In the integrals of these identities, the integrands contain terms with up to second order derivatives of the Green's function for the displacements of the elastic problem.

The Green's function, or fundamental… More >

Deli Gao, Zengxin Zhao

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.1, pp. 29-30, 2011, DOI:10.3970/icces.2011.016.029

Abstract The research on casing corrosion in sour environment by a synergism of sweet corrosion and H2S corrosion has become the basis of casing selection and casing string safety evaluation with more and more sour reservoirs containing high H2S concentration being developed. It is essential to scientifically utilize casing service ability and reasonably control production rate of gas well to achieve the effective and safe developing of gas resources during the safety period of casing service with a precise casing life prediction. Scanning electron microscopy and tensile testing were applied to investigate the corrosion of TP110TS tube steel in stimulant solution… More >

John E Hurtado

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.1, pp. 27-28, 2011, DOI:10.3970/icces.2011.016.027

Abstract The torque-free rotational motion of an asymmetric rigid body is considered. Rather than focus on specific attitude coordinates, a new solution of the attitude matrix in terms of elliptic and circular functions is presented. The approach builds the attitude matrix using orthogonality properties and the concept of integrals of motion. The attitude matrix can give rise to all attitude coordinates, and one convenient set for the current situation is introduced. More >

Norman Hecht

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.1, pp. 25-26, 2011, DOI:10.3970/icces.2011.016.025

Abstract The torque-free rotation of a rigid body has long been a topic of interest to physicists, mathematicians and engineers, including Euler in the 18th century, and continuing to the present day. Numerical solutions to Euler's equations are easy to achieve in an era of cheap computation, but classic solutions to the problem have used principles of angular momentum and energy to develop geometric insights to the problem. Static diagrams can help display these insights, but modern computer graphics hardware and software can truly bring these solutions to life via user-controlled animation.
Besides making visible such abstractions as the angular momentum… More >

H. Wang, P.D. Wu, K.W. Neale

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.1, pp. 23-24, 2011, DOI:10.3970/icces.2011.016.023

Abstract Large strain homogeneous simple shear of Hexagonal Close Packed (HCP) polycrystals is first studied numerically. The analyses are based on the classical Taylor model and the Visco-Plastic Self-Consistent (VPSC) model with various Self-Consistent Schemes (SCSs). In these polycrystal plasticity models, both slip and twinning contribute to plastic deformations. The simple shear results are then extended to the case of solid circular bars under large strain fixed-end torsion, where it is assumed that the solid bar has the same mechanical properties as the element analyzed for large strain simple shear. It is shown that the predicted second-order axial force is very… More >

Jie Qu, Bingye Xu, Quanlin Jin

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.1, pp. 21-22, 2011, DOI:10.3970/icces.2011.016.021

Abstract Large macro-micro coupled constitutive models, which describe metal flow and microstructure evolution during metal forming, are sometimes overparameterized with respect to given sets of experimental datum. This results in poorly identifiable or nonidentifiable model parameters. In this paper, a systemic parameter identification method for the large macro-micro coupled constitutive models is proposed. This method is based on the global and local identifiability analysis, in which two identifiability measures are adopted. The first accounts for the sensitivity of model results to single parameters, and the second accounts for the degree of near-linear dependence of sensitivity functions of parameter subsets. The global… More >