A. Kidess¹, N. Armour¹, S. Dost^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.1, pp. 29-56, 2011, DOI:10.3970/fdmp.2011.007.029

Abstract When a metallic liquid is subject to strong magnetic body forces, the issues of convergence and numerical stability may arise in numerical simulations. Handling of magnetic body force terms needs care. In this work we have studied two open codes and discussed the related issues. Magnetic force and mass transport terms were added to these codes. Handling the stability issues was discussed. The developed systems were validated by two benchmark cases. Then, the dissolution process of silicon into the germanium melt was selected as an application. The objective was the numerical study of the dissolution More >

Yong Kou¹, Ke Jin¹, Xiaojing Zheng^1,2

CMC-Computers, Materials & Continua, Vol.22, No.2, pp. 129-146, 2011, DOI:10.3970/cmc.2011.022.129

Abstract Magnetic shielding needs to be employed to ensure proper operation of some electronic equipment which are sensitive to external magnetic interference, such as cryogenic valves located inside the ITER feeder cubicles. This paper is concerned with the shielding efficiency of the magnetic shielding enclosures. A 3-D theoretical model for Fe-Ni alloy magnetic shielding enclosures based on finite element method (FEM) is obtained with the nonlinear law of magnetization. The influence of shielding materials, enclosure configurations, single or multi- layer designs, and apertures on the shielding efficiency is investigated. It is shown that the proposed model More >

Cheng Wang¹, Jianguo Ning¹, Tianbao Ma¹

CMC-Computers, Materials & Continua, Vol.22, No.1, pp. 73-96, 2011, DOI:10.3970/cmc.2011.022.073

Abstract In this paper, we report high resolution simulations using a fifth-order weighted essentially non-oscillatory (WENO) scheme with a third-order TVD Runge-Kutta time stepping method to examine the features of the detonation for gas and condensed explosives. A two-stage chemical reaction model and an ignition and growth model are employed to describe the chemical reaction process for gas and condensed explosives. Based on the Steger-Warming vector flux splitting method, a splitting method is employed when the vector flux does not satisfy the homogeneity property for simulating detonation wave propagation for condensed explosives. The sensibility of flame More >

C.S. Lin, T.C. Chen, C.C. Yu ,M.E. Wu, Y.H. Tu¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.15, No.3, pp. 103-110, 2010, DOI:10.3970/icces.2010.015.103

Abstract Most old apartments in Taiwan lack fire prevention equipment, making fire awareness and escape difficult, as well as timely fire fighting, which leads to increased death tolls from fire incidents. This research utilizes Fire Dynamics Simulator (FDS) software to analyze and simulate the fire accident that occurred in a single old-style five-story apartment on Siu-Lang Road, Chung-Ho City. In this event, many occupant vehicles were parked at the front door of the apartment building or in nearby parking lanes. The fire engine can only drive in after vehicles were cleared from the fire area, a More >

X.-H. Chen¹, Y.-W. Mai²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.14, No.2, pp. 43-50, 2010, DOI:10.3970/icces.2010.014.043

Abstract A general elastoplastic fracture mechanics theory is proposed for applying the Essential-Work-of-Fracture (EWF) Method to quasi-static and impact toughness characterization. Advanced finite element modeling is developed to simulate the EWF Method using the crack-tip opening angle criterion (CTOA) and the constitutive relation of the material under consideration. For Poly(ethylene-terephlate) (PET) films, the load-displacement curves are calculated for the whole crack propagation process of deeply double-edge notched tensile specimens (DENT) with different ligament lengths so as to determine the total work, the essential work and the non-essential work of fracture. The effects of specimen gauge length More >

D. Kakogiannis¹, D. Van Hemelrijck¹, J. Wastiels¹, S. Palanivelu², W. Van Paepegem², J. Vantomme³, A. Kotzakolios⁴, V. Kostopoulos⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.65, No.1, pp. 75-94, 2010, DOI:10.3970/cmes.2010.065.075

Abstract In the present study the estimation of the blast wave by two types of finite element methods is investigated: Eulerian multi-material modeling and pure Lagrangian. The main goal is to compare and study their ability to predict the clearing effect during blast. Element shape and improvements on the codes are also considered. For the Lagrangian finite element models the load is applied by using an empirical method, deriving from databases, for the time-spatial distribution of the pressure profiles. In the ideal case of the above method the blast load is applied as an equivalent triangular… More >

Y. Inoue¹, R. Kobayashi¹, S. Ogata¹, T. Gotoh¹

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.2, pp. 137-162, 2010, DOI:10.3970/cmes.2010.063.137

Abstract Vibration of a single graphene and a pair of graphenes at micro meter scale induced by air flow is numerically simulated and examined by using a hybrid computational method starting from a microscopic level of description for the graphene. In order to bridge a huge gap in spatial and time scales in their motions, the carbon atoms of the graphene are represented by a small number of coarse grained particles, the fluid motion is described by the lattice Boltzmann equation and the momentum exchange at the boundary is treated by the time averaged immersed boundary… More >

F.P. Mariano¹, L.Q. Moreira¹, A. Silveira-Neto¹, C.B. da Silva², J.C.F. Pereira²

CMES-Computer Modeling in Engineering & Sciences, Vol.59, No.2, pp. 181-216, 2010, DOI:10.3970/cmes.2010.059.181

Abstract A new numerical methodology combining Fourier pseudo-spectral and immersed boundary methods - IMERSPEC - is developed for fluid flow problems governed by the incompressible Navier-Stokes equations. The numerical algorithm consists in a classical Fourier pseudo-spectral methodology using the collocation method where wall boundary conditions are modelled by using an immersed boundary method (IBM). The performance of that new methodology is exemplified in two-dimensional numerical simulations of Green-Taylor decaying vortex, lid-driven cavity and flow over a square cylinder. The convergence rate, the accuracy, the influence of the Reynolds number and the external domain size are analyzed. More >

Y. T. Gu¹, P. Zhuang², F. Liu³

CMES-Computer Modeling in Engineering & Sciences, Vol.56, No.3, pp. 303-334, 2010, DOI:10.3970/cmes.2010.056.303

Abstract Recently, the numerical modelling and simulation for anomalous subdiffusion equation (ASDE), which is a type of fractional partial differential equation(FPDE) and has been found with widely applications in modern engineering and sciences, are attracting more and more attentions. The current dominant numerical method for modelling ASDE is Finite Difference Method (FDM), which is based on a pre-defined grid leading to inherited issues or shortcomings. This paper aims to develop an implicit meshless approach based on the radial basis functions (RBF) for numerical simulation of the non-linear ASDE. The discrete system of equations is obtained by… More >

X. H. Du¹, X. P. Shen¹

CMC-Computers, Materials & Continua, Vol.20, No.3, pp. 225-242, 2010, DOI:10.3970/cmc.2010.020.225

Abstract Aim of this paper is to estimate the integrity of liquefied natural gas (LNG) prestressed storage tank under seismic influence. The coupled Eulerian-Lagrangian (CEL) analysis technique is used to simulate the fluid-structure interaction between LNG and the cylinder of LNG prestressed storage tank. The 3-D model of LNG has been dispersed by Eulerian mesh that is different from traditional analysis method which is called the added mass 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… More >