Study on Mixed Lubrication Property of Planetary Gear Journal Bearing in Wind Turbine Gearbox

Replacing the rolling bearings with journal bearings in the planetary gear of a high-power wind turbine gearbox can improve the power density of the gearbox, but it is unknown whether the journal bearing can achieve good load-bearing and lubrication under the condition of extremely low-speed and heavy-load. Therefore, the lubrication properties of the planetary gear journal bearing is investigated in this paper. Firstly, the viscosity-temperature equations of the special lubricating oils for wind turbine gearbox were determined by rheological test, and then a mixed lubrication model was established considering roughness, viscosity-temperature effect and elastic deformation of bearing bush lining-base composite material. The influence law of the bush relative clearance, roughness, different lubricating oils and inlet temperature, bearing diameter, lining material and thickness on the mixed lubrication properties of planetary journal bearing is obtained, which provides a theoretical basis for the design and application of planetary journal bearing in wind turbine gearboxes refer to.