Research on Mixed Lubrication of the Spindle Journal Bearing in Large Wind Turbines

With the increasing size of wind turbine, journal bearings are expected to overcome the shortcomings of rolling bearings in traditional wind turbines and be applied in the spindle system. In this paper, a hybrid lubrication model of a multi-pad journal bearing is developed specifically for the spindle journal bearing. The model includes Reynolds equation considering surface characteristics and roughness peak contact. A specific solution method is adopted, concluding the finite difference method and the influence coefficient method, to analyze important parameters such as oil film thickness, contact pressure, and oil film pressure on the pad surface. Furthermore, the study investigates various factors that affect the lubrication efficacy of the journal bearings, thereby revealing the tribological properties of multi-pad journal bearing. The results show that the bearing load is mainly supported by some specific bearing plates, and different factors have varying effects on the load ratio distribution among these plates.