Computational efficient flexible multibody dynamics with nonlinear loads and many modes

Abstract or Introduction

The consideration of Finite Element (FE) structures in multibody simulation (MBS) has become an established method, especially when the number of force application points remains moderate. In recent years, a trend can be observed in which distributed loads are considered as well, such as those arising from the contact of two elastic bodies. For finely-meshed FE structures, this results in a large number of possible force application points. In such a case, conventional methods fail, leading to exorbitantly high computation times.

In the last decade, approaches for the reduced computation of deformations inside distributed load application areas were introduced. Special approach vectors are used, called "local modes" here. These local modes lead to a reduction in the involved equations by several orders of magnitude. However, for very large potential load application areas, a large number of local modes is still required—for example, several thousand. Since each local mode leads to a differential equation, a fast numerical time integration is not possible with common methods. In this work, two methodological improvements are proposed for a fast and accurate time integration of such systems.