Multi-Material Structural Topology Optimization for Blast Mitigation Using Hybrid Cellular Auomata

Abstract

Design for structural topology optimization is a method of distributing material within a design domain of prescribed dimensions. This domain is discretized into a large number of elements in which the optimization algorithm removes, adds, or maintains the amount of material. The resulting structure maximizes a prescribed mechanical performance while satisfying functional and geometric constraints. Among di erent topology optimization algorithms, the hybrid cellular automaton (HCA) method has proven to be efcient and robust in problems involving large, plastic deformations. The HCA method has been used to design energy absorbing structures subject to crash impact. The goal of this investigation is to extend the use of the HCA algorithm to the design of advanced armor systems subject to a blast load. The proposed algorithm drives the optimal distribution of a metallic phase and void, or two metallic phases, within the design domain. When the blast pressure wave hits the targeted structure, the uids kinetic energy is transformed into internal energy (IE) inside the solid medium. Maximum attenuation is reached when IE is maximized. Along with an optimum use of material, this condition is satised when IE is uniformly distributed in the design domain. This work makes use of the CONWEP model developed by the Army Research Laboratory and the DRDC plate model developed at Valcartier. The resulting structures show the potential of the HCA method when designing blast mitigating armor structures.