Application of Computational Fluid Dynamics Simulation to Squeeze Film Damper Analysis

Abstract

Squeeze film dampers (SFDs) are used in high-speed turbomachinery to provide external damping to the system. Computational fluid dynamics (CFD) simulation is a highly effective tool to predict the performance of SFDs and obtain design guidance. It is shown that a moving reference frame (MRF) can be adopted for CFD simulation, which saves computational time significantly. MRF-based CFD analysis is validated, then utilized to design oil plenums of SFDs. Effects of the piston ring clearances, the oil groove, and oil supply ports are studied based on CFD and theoretical solutions. It is shown that oil plenum geometries can significantly affect the performance of the SFD especially when the SFD has a small clearance. The equivalent clearance is proposed as a new concept that enables quick estimation of the effect of oil plenum geometries on the SFD performance. Some design practices that have been adopted in industry are revisited to check their validity. Based on simulation results, a set of general design guidelines is proposed.