Dynamic Behavior of Oil Film Journal Bearings in Turbulent Regime : 2nd Report, In the Case of an Imbalanced Rigid Rotor

Abstract

In this second paper, the effects of fluid inertia on the dynamic behavior of an imbalanced rigid rotor supported by the turbulent journal bearings are investigated theoretically and experimentally. Utilizing the expressions for the dynamic oil film force components considering the combined effects of turbulence and fluid inertia forces, the nonlinear equations of motion for the rotor are solved by the inproved Euler's method ahead of time. The journal center trajectories with imbalanced eccentricity ratios ε=0, 0.1 and 0.2 are examined theoretically for Reynolds numbers of Re=2750, 4580 and 5500, and the theoretical results are compared with the experimental results. It is found that the fluid inertia improves the stability of the imbalanced rigid rotor under certain operating conditions.