DYNAMIC TOLOGICAL OPTIMAL DESIGN OF THREE-DIMENSIONAL CONTINUUM STRUCTURES WITH FREQUENCIES CONSTRAINTS

The purpose of present work is to study structural optimal design of dynamics for three-dimensional (3D) continuum structures, and to aim at constructing topological optimal formulation by using ICM method, which is considering weight as object function and fundamental eigenfrequency as constraints. An explicit expression of frequency-constraint(s) with respect to topological variables is obtained based on Rayleigh's quotient and first-order Taylor expansion. And two types of models with filter functions including power function and exponential function are standardized. As a result, the topology optimization problem is solved by the dual quadratic programming. Localized mode and mode switching often occurred in structural optimization with natural frequency constraints are handled by using filter functions and moving constraints in the optimal process. Finally, several numerical examples applying different filter functions in the optimal model are analyzed and discussed to demonstrate the feasibility and efficiency of the proposed method.