Developments of Aerodynamic Foil Bearings for Small High-speed Rotor

Abstract

The developments of simple and high performance bearings applying to a small high-speed rotor are aimed in this research. Two types of aerodynamic foil bearings are proposed here. One of them is named as a spirally-wound foil bearing and another is named as a multi-leaves foil bearing. The former consists of a rigid housing and a flexible foil element, and the latter is constructed with a housing and three foil elements. The foil bearings with several different clearances and foil stiffnesses were manufactured and these effects on the bearing performances such as the stability, the friction torque and the impulse capacity were experimentally investigated in order to derive the design criteria. From the several rotation tests, it was made clear that, with the proper choice of the bearing clearance and the foil stiffness, the foil bearings designed here can achieve sufficiently good operation performances. The multi-leaves foil bearing is superior to the spirally-wound foil bearing in a whole and is hopeful as a simple bearing applying to a small high-speed rotor.