차체 국부 동강성 개선을 위한 위상최적설계

Abstract

This paper presents the structural optimum design method for improving local dynamic stiffness of automotive body structure using topology optimization. The excitation loads from road and engine affect the NVH performance of automotive body structure directly. Since the local dynamic stiffness around excitation loads is known to be important for improving the NVH performance, the topology optimization problem that minimizes the modal displacement at the specific frequency has been applied to find the optimum position of the reinforcement. The modal displacements at few points, however, cannot consider the whole frequency range. In this paper, the local dynamic stiffness constraints of target performance are employed to prevent the performance violation. The hexahedral elements are attached to automotive body structure to find the reinforcement region using topology optimization method. It is confirmed that the optimum design satisfies the target performance over the whole frequency range.