Research on foil thermal features of hydrodynamic air foil bearing with the Three-dimensional heat transfer model

The three-dimensional thermal analysis model of hydrodynamic air foil bearing has been developed to predict the effects of thermal characteristics. Physical parameters varying with temperatures, such as viscosity, density, heat capacity, thermal conductivity, tangent thermal expansion coefficient and Young's modulus have been coupled in this model considering various heat dissipation boundaries of the bearing system, the effects of rotor speed, load and film thickness on the temperature distribution of hydrodynamic air foil bearings were analyzed. The results show that increasing speed and load or reducing film thickness could promote the maximum temperature and viscous dissipation in the bearing system. When the speed rise from 20,000 r/min to 30,000 r/min and 40,000 r/min, the maximum viscous dissipation increasing by 67.4% and 179.4% respectively. The greater the film thickness is, the lower the viscous dissipation and the lower the maximum temperature will be in the bearing. Increasing the rotating speed or reducing the film thickness will promote the global temperature, while increasing the load only promotes the temperature and range of the original high-temperature region, with little impact on the low-temperature region.