This paper is concerned with the optimization of continuum structures under dynamic loading using methods from topology design. The constraint functions are non-linear and implicit, their evaluation requires the resolution of a computation-intensive finite-element analysis performed by a black-box commercial structural mechanics software such as MSC/Nastran. We first present a brief overview of topology optimization methods. Then, we propose a practical topology design methodology for handling problems with dynamic constraints over a range of forcing frequencies. We also introduce a new interpolation scheme for the SIMP method that can remove spurious modes in low-density areas and that allows fill-in. We present encouraging 3-D computational experiments on the design of a specific car component for Renault under acoustic and vibratory constraints, using a public-domain sequential quadratic programming software to drive the overall optimization process.
Technical report LAAS N°05374 LAAS-CNRS, Toulouse, France. July 2005