Optimization of Foam Filled Structures Using Gradient Algorithms

Abstract

This paper proposes a method to improve the application of cellular materials in structural elements. The distribution of the density of different foams is being controlled by material topology optimization method. Due to the very special properties of cellular materials and resulting applications this concept is applied in order to determine the density distribution of polymeric and metal foam as core material in sandwich structures and in thin-walled hollow sections. The first objective that is being investigated is the optimization of the overall buckling behavior. In contrast to the well-known maximization of stiffness leading to lightweight structures under static loading, the second objective is the maximization of the structural energy absorption with respect to quasi-static loading. Due to the large number of design variables in material based topology optimization, mathematical programming (MP) methods combined with variational adjoint methods to determine the sensitivities turn out to be efficient and robust.