A comparative study on inflow schemes of radial throughflow cooling for thermal management of a specific multi-layer gas foil thrust bearing

Abstract

In order to illustrate the effects of radial cooling throughflow on the aerodynamic and thermal behaviors of gas foil thrust bearing, a three-dimensional fluid-solid coupled numerical investigation is conducted for a specific multi-layer gas foil thrust bearing under stable operating conditions in the present study, with two inflow schemes adopted, referred as radially-inward inflow scheme and radially-outward inflow scheme, respectively. The results show that the flow fields and the thermal behavior within the gas foil thrust bearings under the two inflow schemes are significantly different due to the difference in the inflow direction and the effect of centrifugal force caused by the high-speed rotation. The radial cooling throughflow can greatly alleviate the high temperatures in the film layer and improve the cooling capacity, but the increase of mass flow rate causes a non-monotonic change of static bearing load and an enhancement of viscous-shearing heat, as well as a significant rise of the air supply pressure. The radially-inward inflow scheme allows a lower peak temperature and a more uniform temperature distribution on the thrust plate and foil surfaces, while the radially-outward inflow scheme provides a lower area-averaged temperature and consumes less air supply pressure.