The performance evaluation of a surface-textured ultrasonic levitation bearing under multi-operation mode

The load capacity of ultrasonic levitation bearing has become an important factor limiting its practical application in engineering, due to which the load capacity is very small compared to that of other gas bearing. In order to obtain greater load capacity, surface texture is introduced into ultrasonic levitation bearing in this study. A theoretical model considering the geometry parameters and mode shape is established to obtain the running performance of surface-textured ultrasonic levitation bearing, which is solved by using eight-point discrete grid finite-difference method. Influence of driving voltage, rotational speed, eccentricity ratio, texture position, and texture size parameters on load capacity is investigated systematically. Previous experimental results were used to verify the feasibility of the proposed model. The results show that positive texture can effectively improve the load capacity of ultrasonic levitation bearing, especially under ultrasonic levitation mode. Research results are instructive for understanding the lubrication mechanism of ultrasonic levitation bearing and further promote the practical application of the bearing in engineering.