Experimental and theoretical investigation on rotodynamic characterization of porous tilting pad bearings with hermetic squeeze film dampers

Abstract

To improve the performance and expand the application range of gas-lubricated bearings to mainstream high-power devices, load capacity and damping characteristics are the key sticking points. Combining hermetic squeeze film dampers (HSFDs) with porous tilting pad gas bearings (PTPGBs) is a potential option to address this critical issue. A comprehensive bearing rotor test rig was assembled to experimentally investigate the dynamic response of a rigid rotor supported by two HPTPBs (or PTPGB with HSFDs). The rotor with a diameter of 70 cm and a weight of 23.6 kg was successfully accelerated to 20 krpm. Based on the test rig, the effects of bearing parameters such as supply pressure ratio, unbalanced mass, installation of HSFDs and viscosity of the damping fluid on the nonlinear dynamic behaviors are explored. The presence of HSFDs significantly improves the vibration characteristics of bearing rotor systems. This work presents a numerical model of a rotor system supported by PTPGBs with HSFDs to predict the dynamic responses of rotor, and the predictions are in good agreement with the test results. Understanding the effect of different parameters on the dynamic response of the rotor can provide guidance for the optimal design of bearings.