Inlet pressure effects on the static and dynamic characteristics of tilting-pad journal bearings

Abstract

In this paper, the effect of inlet pressure at the bearing entrance on the static and dynamic characteristics of finite-width tilting-pad journal bearings is investigated theoretically. The inlet pressure for a finite-width pad is obtained by assuming the conservation of mechanical energy in the midplane in front of the bearing inlet and a proper polynomial expression as an inlet pressure distribution in the lateral direction. The film pressure is numerically calculated using the inlet pressure as the pressure boundary condition at the leading edge of each pad. Numerical results with or without inlet pressure for a wide range of eccentricity ratios or Sommerfeld numbers are compared. The analysis shows that there is a significant influence of the inlet pressure on the dynamic characteristics of tilting-pad journal bearings, especially on the stiffness coefficient.