Stability Analysis of Hydrodynamic Journal Bearing using Stiffness Coefficients

Journal bearings are widely applied in different rotating machineries. These bearings allow for transmission of large loads at mean speed of rotation. These bearings are susceptible to large amplitude lateral vibration due to self exited instability which is known as oil whirl or Synchronous whirl. This paper presents amethod to determine the Synchronous whirl i.e. Stability of hydrodynamic Journal bearings by using dynamic characteristics such as stiffness coefficients. Analysis shows that Bearing operating at a speed of 800 rpm and 150N load remains stable up to a speed of 1666rpm. This is verified experimentally on journal bearing test rig by operating the bearing up to 1666 rpm and observing the pressure distribution plot .Different journal speeds and loads are considered for the analysis.