Title:Nonlinear Vibration Analysis of Spinning Discontinuous Rotors Considering Different Types of Fluid Bearing ModelsAuthor(s):Stefan Hubinger, Hubert Gattringer, Hartmut Bremer, Karl MayrhoferAbstract:This paper compares different models of fluid bearings in combination with four discontinuous coupled Timoshenko beams. Under consideration are two short journal bearings and one finite length journal bearing. The first two models are only a good approximation for a small length L to diameter D ratio. Therefore, a finite length bearing model as third case study is under consideration, improving the behavior for increasing L/D ratio. Using this model, it is possible to consider fluid bearings with a length to diameter ratio close to one. The systems equations of motion of the spinning Timoshenko beams are derived using the Projection Equation in subsystem representation, leading to partial differential equations. Employing the Transfer-Matrix-Method (TMM) to the linearized system delivers adequate shape functions for the Ritz-Method. Different dynamic models are considered. Four rotors are coupled rotary and diametral. In all cases stepped beams are under consideration, the calculation procedure is not restricted to rotors with constant radii. Simulation results of the different bearing models are presented.Booktitle:Proceedings of SIRM 2011Publisher:Technische UniversitätEditor(s):9. Internationale Tagung Schwingungen in rotierenden MaschinenISBN:978-3-9814163-0-5Page Reference:10 page(s)Publishing:2/2011Series:9. Internationale Tagung Schwingungen in rotierenden Maschinen