Generalized Dynamic Reduction in Finite Element Dynamic Optimization

AUTOMATED redesign for frequency changes of un-damped structural systems is carried out through generalized dynamic reduction. The redesign involves a nonlinear perturbation from a baseline design. Generalized coordinates are introduced to transform the original problem into a subspace of small size. A nonlinear mathematical programming scheme is applied in the reduced subspace. of the eigenvectors. If a truncated set of q modes [G*] is used, the relation may be only approximate, where (uq} is the vector of dynamic degrees of freedom. As in static condensation, the physical degrees of freedom can be divided into two groups, Contents When the analysis of dynamic systems shows undesirable natural frequencies and mode shapes, it is not easy to kno