Arunn Narasimhan^*, Kaushal Kumar Jha

Frontiers in Heat and Mass Transfer, Vol.2, No.3, pp. 1-8, 2011, DOI:10.5098/hmt.v2.3.3005

Abstract Pan Retinal photocoagulation (PRP), a retinal laser surgical process, is simulated using a three-dimensional bio-heat transfer numerical model. Spots of two different type of array, square array of 3 × 3 spots and a circular array of six spots surrounding a central spot, are sequentially irradiated. Pennes bio-heat transfer model is used as the governing equation. Finite volume method is applied to find the temperature distribution due to laser irradiation inside the human eye. Each spot is heated for 100 ms and subsequently cooled for 100 ms with an initial laser power of 0.2 W. More >

Sina Alavi, Mohammad Passandideh-Fard^*

Frontiers in Heat and Mass Transfer, Vol.2, No.2, pp. 1-9, 2011, DOI:10.5098/hmt.v2.2.3007

Abstract In this paper, a numerical study is performed to investigate the effects of thermal shrinkage on the deposition of molten particles on a substrate in a thermal spray process using the Volume-of-Fluid (VOF) method. Thermal shrinkage is a phenomenon caused by the variation of density during cooling and solidification of a molten metal. The Navier-Stokes equations along with the energy equation including phase change are solved using a 2D/axisymmetric mesh. The VOF method is used to track the free surface of molten particles, and an enthalpy-porosity formulation is used to model solidification. For the normal More >

Yan Liu, Xiong Zhang, Yanping Lian

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 69-70, 2011, DOI:10.3970/icces.2011.018.069

Abstract The analyses of bird strike are of great concern to aircraft designers, because bird strikes can cause very serious problems to flight safety. Meshfree particle methods are suitable for simulating bird strike problems owing to their advantages in dealing with large deformation, fracture and fluid-structure interaction. The material point method (MPM) is employed to analyze the impacting of bird on windshield in this talk in which both the bird and the windshield are discretized by material points. The material model of the bird is accompanied by an appropriate equation of state (EOS) to model the More >

P.F. Yang, X. Zhang, Y. Liu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.3, pp. 71-72, 2011, DOI:10.3970/icces.2011.017.071

Abstract The material point method (MPM) is extended to the simulations of material fragmentation due to detonation. A crack modeling scheme based on contact algorithm with material failure process is developed to study the dynamic crack propagation in plastic media. Particles after failure are transformed to a different velocity field by contact method, which makes the crack surface not constrained by grid lines and free to propagate dynamically in any direction even when the material experiences large plastic strain increments. The random characterization of the fragmentation can be described by both microscopic defect and macroscopic failure.… More >

Hongyang Li, Cheng Chen, WeiWei Li, Yanjing Zhang, Xiaopeng Liu, Yandong Wang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 47-48, 2011, DOI:10.3970/icces.2011.020.047

Abstract Large numbers of micro lattice plastic deformation of grains set up the macro plastic deformation of polycrystal metallic materials under different macro boundary condition. And the macro homogeneous deformation is in fact the statistical result of micro anisotropic lattice plastic flow. Both of the macro and micro deformation were influenced by intrinsic initial stress, which was intrinsic in the component from micro scale impurity to macro scale non-uniform deformation. In this paper, focused on the engineering application and further damage evaluation, effect of macro initial stress on the macro and micro plasticity deformation of sample More >

Li Shan, Ming Cheng, Kaixin Liu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.3, pp. 87-88, 2011, DOI:10.3970/icces.2011.019.087

Abstract In the present paper, a combined scheme of discrete element method (DEM) and meshless method for numerical simulation of impact problems is proposed. Based on the basic principle of continuum mechanics, an axisymmetric DEM framework is estabilished for modeling the elastoplastic behavior of solid materials. A failure criterion is introduced to model the transformation from a continuum to a discontinuum. The friction force between contact elements is also considered after the failure appears. So our scheme can calculate not only the behavior of continuum and discontinuum, but also the transformation process from continuum to discontinuum. More >

Ryoichi Yamamoto

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 37-38, 2011, DOI:10.3970/icces.2011.018.037

Abstract We developed a unique method for direct numerical simulations (DNS) of dense colloidal dispersions [3, 5]. This method, called the smoothed profile method (SPM), enables us to compute the time evolutions of colloidal particles, ions, and host fluids simultaneously by solving Newton, advection-diffusion, and Navier-Stokes equations so that the electro- hydrodynamic couplings can be fully taken into account. We have applied the SPM successfully for simulating dynamics of various particle dispersions, including colloids in liquid crystals [1, 2], electrophoresis of charged colloids [4, 5], particle diffusion in fluids [7, 8], dispersion rheology [9, 11], tumbling More >

X.H. Du, X.P. Shen

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.3, pp. 81-82, 2011, DOI:10.3970/icces.2011.016.081

Abstract Aim of this paper is to simulate the fluid-structure interaction of liquefied natural gas (LNG) prestressed storage tank under seismic influence. The coupled Eulerian-Lagrangian (CEL) analysis technique is used to simulate the hydrodynamic interaction between LNG and the cylinder of LNG prestressed storage tank. The 3-D model of LNG has been dispersed by Eulerian mesh which is different from traditional added mass analysis method. Meanwhile, both of the 3-D models of prestressed rebar and concrete structure are dispersed by Lagrangian mesh. Following conclusions are obtained: 1) Natural frequency of the whole model has been obtained… More >

Alamusi, Yaolu Liu, Ning Hu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.2, pp. 57-58, 2011, DOI:10.3970/icces.2011.016.057

Abstract In this work, we propose a 3 dimensional (3D) numerical model to predict the piezoresistivity behaviours of a nanocomposite material made from an insulating polymer filled by carbon nanotubes (CNTs). This material is very hopeful for its application in highly sensitive strain sensor by measuring its piezoresistivity, i.e., the ratio of resistance change versus applied strain. In this numerical approach, a 3D resistor network model is firstly proposed to predict the electrical conductivity of the nanocomposite with a large amount of randomly dispersed CNTs under the zero strain state. By focusing on the fact that… More >

Qiang Li, Jie Ouyang¹, Xuejuan Li², Guorong Wu², Binxin Yang²

CMES-Computer Modeling in Engineering & Sciences, Vol.74, No.3&4, pp. 247-268, 2011, DOI:10.3970/cmes.2011.074.247

Abstract A unified mathematical model is proposed to predict the short shot, primary and secondary gas penetration phenomenon in gas-assisted injection molding (GAIM) process, where the Cross-WLF model and two-domain modified Tait equation are employed to simulate the melt viscosity and density in the whole process, respectively. The governing equations of two-phase flows including gas, air and polymer melt are solved using finite volume method with SIMPLEC technology. At first, two kinds of U-shaped gas channels are modeled, where the shape corner and generous corner cases are studied. At last, as a case study, the short More >