Efficient Flexible Multibody Models for Tilting Pad Journal Bearings

Abstract

Tilting pad journal bearings (TPJBs) are key components in modern rotating machines. They require accurate modeling to describe their behavior, and we considered the thermo-elasto-hydrodynamic approach. Thermo-elasto-hydrodynamic (TEHD) models are a powerful tool for machine design and analysis, but they have to assure a good compromise between accuracy and numerical efficiency. Current multi-physics TEHD models of TPJBs are very accurate; however, their numerical efficiency is still far from being satisfying for industrial applications. To partially fill this gap, we propose an innovative modeling approach based on efficient flexible multibody techniques, such as the Floating Frame of Reference Formulation (FFRF) and some extensions that can be easily coupled with different fluid dynamic models to describe the whole TPJB. The model was tested on a real TPJB geometry and validated through experimental tests. The results are encouraging and show the effectiveness of the proposed approach. Finally, the model proposed can be applied in different engineering fields, such as Oil & Gas and aeronautics, where TPJBs are typically used, where it is fundamental to always reach better performance with low energy consumption and where it is particularly important to have an efficient and accurate model to simulate long period times with brief simulation times.

Keywords

• tilting pad journal bearing
• thin film lubrication
• hydrodynamic lubrication