An efficient computational procedure for random vibro-acoustic simulations

We discuss a new method for handling random acoustic excitations in finite-element models. The idea is to approximate the cross power spectral density matrix of the response by a low rank matrix. We illustrate the low rank approximation can be computed efficiently by the implicitly restarted block Lanczos method. The novelty lies in applying the Lanczos method to the cross power spectral density matrix of the response rather than the excitation. We give a theoretical explanation for finite-element models with modal damping.