Simulation and Experimental on Thermal Behavior of Hydrostatic Thrust Bearing Based on Superhydrophobic/Oleophobic Surface

Abstract

The temperature rises of the oil film in hydrostatic bearings at high speed lead to a reduction in load capacity, accuracy, and stability. In this paper, a superhydrophobic/oleophobic surface with a micro-bulge structure is proposed. The surface is prepared by laser cross-scanning and chemical modification. The contact angle (CA) of the surface is 138 deg and the boundary condition of the surface is modified from non-slip to slip condition. The relationship between the slip length and the height of the micro-bulge structure is established by rheological experiments. By the simple partial simulations, the validity of the temperature rise reduction on the superhydrophobic/oleophobic surface is verified. Then a bearing test rig was set up to measure the temperature and load capacity of bearings at multiple points, and the performance of smooth primary surface/structured oleophobic surface thrust bearings was compared. Results show that the structured bearing has a lower oil film temperature and higher load capacity than the smooth bearing. The prepared oleophobic surface can effectively suppress the temperature rise at high-speed conditions and significantly increase the bearing load capacity.