EXPERIMENTAL INVESTIGATION ON THERMOHYDRODYNAMIC PERFORMANCE OF LARGE TILTING-PAD JOURNAL BEARING INCLUDING THE INLET PRESSURE EFFECT

The thermohydrodynamic performance of a large tilting-pad journal bearing including the inlet pressure effect is investigated experimentally. The continuous film pressure, film thickness and shaft surface temperature, and bearing surface temperature are measured along with the shaft speed and the bearing load for various flow rates. Considerably large inlet pressure is observed at the entrance of each pad, especially the lower pads. The inlet pressure is increased by the increase of shaft speed as well as bearing load, but is almost independent of the flow rate. The upper pads always maintain a slight wedge film shape owing ta the inlet pressure, and scraping is not observed in the upper pads. It is observed that the shaft surface temperature is constant in the circumferential direction and increases with the increase of shaft speed in both low and high shaft-speed regions; however, there exists a transition region where the shaft surface temperature decreases with the increase of shaft speed.