A study on foil bearings (on the effect of small wrap angle)

Abstract

There are many studies on the self-acting foil bearing, but most are based on the assumption that the wrap angle of foil is large enough for its effect on the basic characteristics of the bearing to be negligible. When the wrap angle is not so large, its effect is not negligible. In this paper, the effect of small wrap angle on the foil displacement and the pressure distribution are obtained theoretically and experimentally. The effect of small wrap angle on these basic characteristics is found to be characterized in terms of wrap angle B; radius of shaft R; foil speed U; effective foil tension TSUBo; representative foil displacement hSUBo and fluid viscosity MU. As the value of this parameter decreases, the effect of the wrap angle increases and the foil profile and the pressure distribution become different from those in the case of large wrap angle