Static and dynamic behaviors of a cylindrical hydrodynamic journal bearing operating at very low Sommerfeld numbers

Abstract

Plain journal bearings are commonly equipping various rotating machineries from small electrical motors to large generators, turbines and pumps. They are preferable to rolling element bearings because of their long life performance, low cost, quiet operation, high damping properties, split design, and smaller outside dimension. In this paper the static and dynamic characteristics of a cylindrical journal bearing working in critical conditions, namely at very low speed and high specific pressure, are described. A bearing with the nominal diameter of 160mm and the length of 145mm was used. The rotational speed was fixed at very low speed of 60rpm while the applied static load in the vertical direction ranges in the Sommerfeld number from 0.0086 to 0.1314. Measurements of static position of the shaft, hydrodynamic pressure, temperature profiles, and dynamic coefficients have been presented and discussed.