chapter  6
90 Pages

Design of Fluid Film Bearings

Fluid film bearings are a common means of supporting rotating shafts in rotating machinery. In such bearings a pressurized fluid film is formed with adequate thickness to prevent rubbing of the mating surfaces. Bearing behavior can be calculated for any given geometry and boundary conditions. The equations of motion are numerically integrated for sample conditions in order to illustrate the dynamic behavior of the rotor for different values of the bearing design parameters. The chapter presents an automated system for the selection of the main design parameters to optimize the performance of the hydrodynamic bearing. The modified Sommerfeld number can then be utilized in the standard formulas to calculate eccentricity ratios, oil flow, frictional loss, and temperature rise, as well as stiffness and damping coefficients for full film bearings. M. J. Braun et al. investigated different aspects of the thermal effects in the lubricant film and the thermohydrodynamic phenomena in a variety of film situations and bearing configurations.