Mingchao Cai, Chun Yang, Mehmet H. Kural, Richard Bach, David Muccigrosso, Deshan Yang, Jie Zheng, Kristen L. Billiar, Dalin Tang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 97-104, 2011, DOI:10.3970/icces.2011.019.097

Abstract Image-based computational modeling has been introduced for vulnerable atherosclerotic plaques to identify critical mechanical conditions which may be used for better risk assessment and rupture predictions. In vivo patient-specific coronary plaque models are lagging due to limitations on non-invasive image resolution, flow data, and vessel material properties. We propose a procedure where intravascular ultrasound (IVUS) imaging, biaxial mechanical testing and computational modeling are combined together to acquire better and more complete plaque data and make more accurate plaque vulnerability assessment and predictions. More >

Duning Li, Yufeng Niei?a, Xuemei Zhou, Li Cai

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.3, pp. 75-76, 2011, DOI:10.3970/icces.2011.019.075

Abstract In this study, the efficient discrete model including the resin infusion and the fiber compaction is developed to simulate the RFI (resin film infusion) process. The non-linear governing equations are derived by the Darcy's law, the Terzaghi's law and the continuity equations. The finite element method and the finite difference method are used to discretize the proposed equations, and the VOF method is used to track the filling front. Compared with the analytical results of Park, our numerical results agree well with them. Furthermore, we analyze the RFI process of BMI/G0814, and simulate the resin More >

Sanghyun Shim, Kwangjin Kim, Sangchul Lee, Sangho Ko, Jayoung Kang, Dongyoung Rew, Gwanghyeok Ju

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.3, pp. 73-74, 2011, DOI:10.3970/icces.2011.019.073

Abstract The aim of this paper is to discuss the main issues related to modeling and simulation of the Korean lunar module. Lunar module usually consists of a rigid platform, attitude control actuators and a fuel tank. For dynamical modeling, we first assumed the lunar module as a rigid body and derived equations of motion by considering allocation of reaction thrusters and reaction wheel assembly(RWA). Fuel sloshing in lunar module and its influence on attitude dynamics are an important issue in the research field of space technology. In order to include the effect of fuel sloshing More >

De-Shin Liu, Zhen-Wei Zhuang, Cho-Liang Chung

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.2, pp. 39-40, 2011, DOI:10.3970/icces.2011.019.039

Abstract A two-dimensional heterogeneous hybrid moisture element method (HHMEM) for modeling transient moisture diffusion in permeable fiber-reinforced polymer composites is proposed in this paper.
The HHMEM scheme is based on a heterogeneous hybrid moisture element (HHME), whose properties are determined by equivalent moisture capacitance and conductance matrixes calculated using the conventional finite element formulation with the similarity mass/stiffness property and matrix condensing operations. A coupled HHME-FE scheme is developed and implemented in computer codes MATLAB to analyze the transient moisture diffusion characteristics of polymeric composite materials containing multiple permeable fibers. The analysis commences by comparing the… More >

Yongzheng Ma, Hong Zheng

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.1, pp. 7-8, 2011, DOI:10.3970/icces.2011.019.007

Abstract The traditional Discontinuous Deformation Analysis (DDA) method, like other Discrete Element Methods, is created to model the discrete block system. The extended DDA method based on meshless interpolations means utilizing meshless interpolations, usually the Moving Least-Squares interpolations, to present block displacement field. In the new extensions here, the effects of earthquake, excavation and bolt reinforcement on the assemblages of large blocks are modeled: for modeling earthquake, the initial acceleration value from earthquake at certain DDA time step can be interpolated from the earthquake acceleration vs. time curve; the modeling of excavation is by reversing in-situ More >

Zhigang Guo, Zhi Sun

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 61-62, 2011, DOI:10.3970/icces.2011.018.061

Abstract An efficient approach to identify multiple cracks in a slender beam using the frequency response function data is presented. It is formulated in a general form from the dynamic stiffness equation of motion for a structure and then applied to a slender beam. The cracks are modeled by rotational springs and the frequency response function is computed based on a spectral element model by the spectral finite element. The procedure gives a linear relationship explicitly between the changes of the measured frequency response function and crack parameters. The inverse problem is solved iteratively for the More >

Yan-Bin Jia

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.2, pp. 43-44, 2011, DOI:10.3970/icces.2011.016.043

Abstract The robot hand applying force on a deformable object will result in a changing wrench space due to the varying shape and normal of the contact area. Design and analysis of a manipulation strategy thus depend on reliable modeling of the object's deformations as actions are performed. The first part of this talk is concerned with modeling of shell-like objects grasped by a robot hand. We present a formulation of extensional, shearing, and bending strains in terms of geometric invariants including the principal curvatures and vectors, and their related directional and covariant derivatives. A computational… More >

Wei Huang^∗,†, Yi Wah Mak^*, Peter C. Y. Chen^‡§

Molecular & Cellular Biomechanics, Vol.8, No.2, pp. 91-104, 2011, DOI:10.3970/mcb.2011.008.091

Abstract A molecular configuration tensor Pij was introduced to analyze the distribution of fibrous proteins in vascular cells for studying cells and tissues biomechanics. We have used this technique to study the biomechanics of vascular remodeling in response to the changes of blood pressure and flow. In this paper, the remodeling of the geometrical arrangement of F-actin fibers in the smooth muscle cells in rat's pulmonary arteries in hypoxic hypertension was studied. The rats were exposed to a hypoxia condition of 10% for 0, 2, 12, and 24 hr at sea level. Remodeling of blood vessels… More >

De-Shin Liu¹, Zhen-Wei Zhuang¹, Shaw-Ruey Lyu^2,3, Cho-Liang Chung⁴, Pai-Chen Lin¹

CMC-Computers, Materials & Continua, Vol.26, No.2, pp. 111-136, 2011, DOI:10.3970/cmc.2011.026.111

Abstract This study proposes a two-dimensional heterogeneous hybrid moisture element method (HHMEM) for modeling transient moisture diffusion in permeable fiber-reinforced polymer composites.
The HHMEM scheme is based on a heterogeneous hybrid moisture element(HHME), with properties determined through an equivalent hybrid moisture capacitance/conductance matrix. This matrix was calculated using the conventional finite element formulation in space discretization as well as the θ-method in time discretization with similar mass/stiffness properties and matrix condensing operations. A coupled HHME-FE scheme was developed and implemented in computer code MATLAB in order to analyze the transient moisture diffusion characteristics of composite materials containing multiple… More >

L.Q. Moreira¹, F.P. Mariano², A. Silveira-Neto¹

CMES-Computer Modeling in Engineering & Sciences, Vol.75, No.2, pp. 113-140, 2011, DOI:10.3970/cmes.2011.075.113

Abstract Turbulence in fluid flow is one of the most challenging problems in classical physics. It is a very important research problem because of its numerous implications, such as industrial applications that involve processes using mixtures of components, heat transfer and lubrication and injection of fuel into the combustion chambers and propulsion systems of airplanes. Turbulence in flow presents characteristics that are fully nonlinear and that occur at high Reynolds numbers. Because of the nonlinear nature of turbulent flow, an increase in the Reynolds number implies an increase in the Kolmogorov wave numbers, and the flow… More >