Design automation of a laminated armor for best impact performance using approximate optimization method

Abstract

Values of characteristic parameters such as thickness have big influence on the impact behavior of a laminated armor. Determination of those values for an optimum laminated armor usually requires evaluation of many computationally costly impact analyses. In this paper,, automated, efficient and effective determination of design parameters in a laminated armor for best impact performance is investigated using an approximate optimization method. The approximate optimization method is generated by coupling a parametric preprocessor, finite element analysis software, response surface approximations and a numerical optimization algorithm. The whole coupling is achieved through a commercial code, ANSYS Design Optimization Module. The laminated armor of interest consists of three layers. The frontal layer is alumina ceramic, and it is supported by a 4340 steel mid-layer and a 2024-T3 aluminum rear layer. The armor is impacted by a projectile with velocities of 1000 and 2000 m/s. The surface normal of the armor has an oblique angle with the projectile's moving direction. The 3-D impact analysis of the armor is conducted using non-linear explicit dynamic finite element code ANSYS/LS-DYNA. Optimization of the armor is performed to find the best thickness values of layers and oblique (orientation) angle towards the least penetration of the projectile. (C) 2003 Elsevier Ltd. All rights reserved.