Efficient matrix randomisation methodology for reduced spacecraft models in stochastic FEM-BEM vibroacoustc problems

In this paper, the mathematical framework for a computationally efficient stochastic finite element method (FEM) is outlined. It is devised for a range of applications in structural dynamics, where uncertainties need to be reliably dealt with in the context of reduced model formulations. It allows random mass and stiffness matrices to be robustly generated at the subsystem level in component mode synthesis (CMS) applications. The technique is validated for the particularly challenging case of mid-frequency FEM-FEM vibroacoustic analysis of a spacecraft structure. Results are compared against both test data and full parametric Monte-Carlo simulation. Finally, the method’s applicability to coupled vibroacoustic problems utilising hierarchical matrix boundary element method (BEM) acoustic formulations is evaluated