Thermodynamics and Stability Analysis of High-Speed Hydrodynamic Journal Bearing

Abstract

The thermodynamic model of the high-speed hydrodynamic journal bearing is established to analyze the influence of the temperature-viscosity effect on the oil film in aspects of dynamic characteristics and stability. The coupling governing equations of the bearing including the Reynolds equation, energy equation and viscosity-temperature equation are solved to obtain the pressure distribution, temperature distribution and viscosity distribution, according which the stiffness coefficients and damping coefficients are acquired. Then the stability analysis of the bearing is processed based on Routh-Hurwitz stability criteria. The result indicates that when temperature-viscosity effect is taken into account, the dynamic characteristics, threshold speed and threshold mass show distinct decrease, and the degree of which is positive relative to the rotating speed, the eccentricity and the aspect ratio.