Stress recovery with Krylov-subspaces in reduced elastic multibody systems

A method for the recovery of stresses in reduced elastic multibody systems is presented. Elastic coordinates of a flexible body belonging to a reduced elastic multibody system are therefore premultiplied with a matrix of shape functions for stresses. Whereas the classic procedures for stress recovery in elastic multibody systems use shape functions for stresses that belong to eigenmodes and particular modes, this work also investigates shape functions for stresses that are derived from a Krylov-subspace projection. The presented method for stress recovery is implemented in a process chain containing different software tools and allows the evaluation of stresses during the runtime of the elastic multibody simulation. Accordingly, the performance of the developed process is examined with the help of a simple example. Results show that the usage of shape functions for stresses that are derived from a Krylov-subspace projection can improve the approximation of stresses in a user-defined frequency range.