Super-element global modal parameterization for efficient inclusion of highly nonlinear components in multibody simulation

摘要

Over the last decades, higher and higher accuracy is expected from flexible multibody models. Accurate flexibility descriptions and detailed contact algorithms have been mostly developed with this aim. In practice, linearized models are often used at the expense of severe accuracy loss in order to improve simulation times. Several multibody packages have also been developed for the simulation of nonlinear components, but these typically lead to elevated simulation times. Alternatively, a cosimulation with a nonlinear finite element package can be performed, but this leads to very inefficient schemes. In order to allow a generic introduction of nonlinear components in multibody simulation packages, this paper introduces a novel nonlinear model reduction technique for nonlinear components, namely the Super-element Global Modal Parameterization (SE-GMP). The approach is aimed at reducing complex models of nonlinear components, while still taking the important nonlinear effects into account, in order to create a relatively simple model which can easily be coupled with other components in a multibody model. The proposed approach is based on the GMP formulation which is a nonlinear system level model reduction technique for (flexible) multibody systems. This work discusses the reduction procedure and different choices for the reduction space. Moreover, a strong focus is put on an appropriate choice of coordinates in order to allow for a convenient interfacing with multibody descriptions. Finally, the approach is demonstrated by the simulation of a slider-crank mechanism with a nonlinearly deforming crank.