Effect of the load direction on non-nominal five-pad tilting-pad journal bearings

In this paper, a theoretical analysis of the influence of the load direction on the characteristics of a five-pad tilting-pad journal bearing (TPJB) is investigated. An analysis is performed for a TPJB using a non-nominal geometry, that is, with a different preload factor for each pad. The analytical results are then compared with the experimental measurements for a real bearing having pads with different geometries due to manufacturing errors. The results show that the load direction has considerable effects on both the static and dynamic characteristics of the TPJB. A robust estimation method is introduced for the calculation of experimental dynamic coefficients. The procedure for the bearing geometry estimation from the experimental measurement of the clearance profile is also described.