Multibody systems with lubricated contacts - cavitation, interface coupling, reduction and quasi-Newton techniques

Elastohydrodynamic lubricated contacts occur in various machine elements and allow for a wear resistant power transmission while motion of rolling elements is present. Their accurate modeling and simulation enables better system and component designs with respect to lifetime, wear, vibration and material. This work treats numerical methods for a more efficient simulation of multibody systems with elastohydrodynamic contacts. It deals with a stationary and a mass-conservative cavitation model, which are reformulated using methods of convex analysis. It suggests a monolithic solution strategy for the coupled problem of mechanic and hydrodynamic equations. A quasi-Newton method is analyzed as a solution technique. Different interface coupling methodologies are investigated for non-conforming fluid and structural meshes for the elastohydrodynamic problem and a novel load dependent approach is developed to reduce the elastic degrees of freedom of the lubricated interfaces. Numerical examples as well as an experimental validation of a rotor test rig demonstrate the applicability of the developed calculation methods.