Study on the structures of fluid flows in the annular space formed by a submerged tilting pad journal bearing

In this study, the Taylor vortices of the film flow in the bearing clearance and so-called cavity flow between pads in a submerged tilting pad journal bearing were visualized by means of a tracer method. The effects of pad arc extent and pad inclination (from leading to trailing edges) on fluid flows, especially on the structures of Taylor vortices and cavity flow were investigated. The critical Taylor number of the film flow increased with an increase in pad inclination slightly. The pitch of array of the Taylor vortex rings at the critical Taylor number was, however, scarcely influenced by the pad inclination. The pitch was likely fixed by the mean clearance over the pad. Two-dimensional cavity flow field (in the central section perpendicular to the rotation axis) between pads was measured by a Particle Image Velocimetry to investigate the interaction of film flow and cavity flow between pads. The Taylor vortices out of the preceding pad were almost carried over the cavity region into succeeding pad, and hardly mixed with the cavity flow. This phenomenon is important in relation to the oil exchange between the film and cavity flows.