Eccentricity Measurements on a Five-pad Tilting Pad Journal Bearing

The study of static and dynamic effects plays a key–role in the field of rotor dynamics to evaluate the behavior of hydrodynamic bearings. This paper describes an experimental apparatus and the procedure for measuring the static eccentricities and the bearing clearance distribution in a five–pads tilting pad journal bearing (TPJB). The tests have been carried out on a five– pads TPJB with nominal diameter of 100 mm, length–to– diameter ratio (L/D) of 0.7 and load–on–pad (LOP) configuration. The results show that the clearance profile, with a pentagon–shape, is a function of the operating temperature and of the pad dimensions. Besides, the barycenter of the clearance profile is very close to the equilibrium position of the journal center at low rotational speeds. A procedure for the evaluation of the bearing clearance with experimental measurement is also described.