Numerical Investigation on Aerodynamic and Thermal Characteristics of Hydrodynamic Foil Thrust Bearing with a Radial Cooling Inflow

In accordance with the need of thermal management of hydrodynamic foil thrust bearing with high rotational speed，a steady three-dimensional fluid-solid coupled numerical simulation is performed to illustrate the effects of rotational speed，radial inflow mass-rate and outlet scheme on aerodynamic and thermal behaviors of foil thrust bearing with a radial cooling inflow，by assuming that the bearing works in a stability condition with fixed elastic deformation. The results show that the outlet scheme of film-layer gap has an obvious influence on the pressure distribution on the rotating disc surface. Compared with the film-layer sealed outlet situation，the radial inflow is able to penetrate the film-layer gap in the unsealed outlet situation，improving the cooling capacity of rotating disk and top thrust foil as well as decreasing the pressure drop of radial inflow. However，a negative influence of 10.7%∼32.5% reduction on the thrust bearing capacity is also introduced by this unsealed outlet scheme. The increase of radial inflow mass-rate not only enhances the cooling capacity，but also strengthens the thrust bearing capacity. In general，the effect of film-layer outlet scheme on the cooling capacity of rotating disc and top thrust foil behaves more pronouncedly under higher rotational speeds. Its influence on the pressure drop of radial inflow and the thrust bearing capacity is more significant under bigger radial inflow situations，where the increasing in thrust bearing capacity rises from 0.8% to 23.3% with mass-rate and the pressure drop increases by 0.5% to 15%. © 2022 Journal of Propulsion Technology. All rights reserved.