Lior Banai

CMES-Computer Modeling in Engineering & Sciences, Vol.88, No.5, pp. 351-366, 2012, DOI:10.3970/cmes.2012.088.351

Abstract The explosive Engineering field is a costly one in which not every organization can effort the time and money it takes to performed field tests on its explosives. The purpose of this article is to present a program that was developed in the Israeli Navy for performance estimations and safety issues of warheads and explosives. With a relative small developing time one can create a tool that gives preliminary results in a few minutes without the need to design and order a field tests or run finite elements analyses. By implementing a few known models, in this tool, the user… More >

A.P.S.Selvadurai¹

CMES-Computer Modeling in Engineering & Sciences, Vol.52, No.3, pp. 259-278, 2009, DOI:10.3970/cmes.2009.052.259

Abstract The paper deals with a computational approach for modelling the fragmentation of ice sheets during their impact with stationary structures. The modelling takes into consideration the intact continuum behaviour of the ice as a rate-sensitive elastoplastic material. During impact, the ice sheet can undergo fragmentation, which is controlled by a brittle strength criterion based on the current stress state. The fragmentation allows the generation of discrete elements of the ice sheet, the movements of which are governed by the equations of motion. The contact between individual fragments is governed by a Coulomb criterion. The individual fragments can themselves undergo further… More >

Pengfei Yang¹, Yan Liu¹, Xiong Zhang^1,2, Xu Zhou³, Yuli Zhao³

CMES-Computer Modeling in Engineering & Sciences, Vol.85, No.3, pp. 207-238, 2012, DOI:10.3970/cmes.2012.085.207

Abstract The material point method is extended to the simulations of fragmentation driven by detonation. A crack modeling scheme based on contact algorithm with material failure process is developed to study the dynamic crack propagation in plastic media. When considering microscopic damage of material, the plastic behavior is described by Gurson model with randomly-distributed initial void of material points. Gurson model can degenerate to J2 plastic theory while the microscopic void is ignored, in which situation the Weibull random failure scheme will be used. Meanwhile, a background-grid-based searching method is proposed to capture the statistical feature of the fragmentation. The scaling… More >

LumingShen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.49, No.1, pp. 23-46, 2009, DOI:10.3970/cmes.2009.049.023

Abstract A bifurcation-based simulation procedure is proposed in this paper to explore the transition from localization to decohesion involved in the glass fragmentation under impact loading. In the proposed procedure, the onset and orientation of discontinuous failure of glass is identified from the bifurcation analysis based on a rate-dependent tensile damage model. The material point method, which does not involve fixed mesh connectivity, is employed to accommodate the multi-scale discontinuities associated with the fragmentation of glass using a simple interface treatment. A parametric study has been conducted to demonstrate the effects of specimen size and impact velocity on the evolution of… More >

E. Lescoute¹, T. De Rességuier¹, J.-M. Chevalier², J. Breil³, P.-H. Maire², G. Schurtz³

CMC-Computers, Materials & Continua, Vol.22, No.3, pp. 219-238, 2011, DOI:10.3970/cmc.2011.022.219

Abstract With the ongoing development of high energy laser facilities designed to achieve inertial confinement fusion, the ability to simulate debris ejection from metallic shells subjected to intense laser irradiation has become a key issue. We present an experimental and numerical study of fragmentation processes generating high velocity ejecta from laser shock-loaded metallic targets (aluminium and gold). Optical transverse shadowgraphy is used to observe and analyze dynamic fragmentation and debris ejection. Experimental results are compared to computations involving a fragmentation model based on a probabilistic description of material tensile strength. A correct overall consistency is obtained. More >