Investigation of Load Direction on a Five-Pad Tilting Pad Journal Bearing with Variable Clearance

Most of the studies about tilting pad journal bearings (TPJBs) are for load-on-pad (LOP) or load-between-pad (LBP) configurations. In both bearing models and experimental tests, the load is often assumed along the vertical direction only and the geometry of the bearing is the same for each pad, i.e. the ideal one, which corresponds to an axial symmetry of the bearing. In this paper a theoretical analysis of the influence of the load direction on both the static and the dynamic characteristics of a five-pads TPJB is investigated, that is, the different loading configurations in the range between LOP and LBP are investigated. The analysis is performed for a TPJB with a non-nominal geometry, that is, with a different preload factor for each pad. Then, the analytical results are compared with experimental results. These results show that the load direction has considerable effects on both the static and the dynamic characteristics of the TPJB.