Flow and thermal analysis of oil air two-phase medium in bearing chamber

To obtain the flow and thermal analysis methods of oil air two-phase medium in bearing chamber，and find out the rule of flow and heat transfer in oil air two-phase medium, the flow velocity, temperature distribution, volume fraction and heat transfer coefficient distribution of two-phase medium in the engine bearing chamber were analyzed by CFD methods. Based on the local temperature in different positions of the bearing chamber, the heat transfer coefficient was obtained by calculating the heat flow under the temperature gradient method. The results showed that: the flow velocity of two-phase medum increased first then decreased with the increase of radial height, its maximum appeared when the dimensionless radial height was 0.6. The temperature of two-phase medium in the area between the rotor and the wall in the bearing chamber decreased first and then increased during the increase of radial coordinates. The oil in the bearing chamber was mainly distributed on the oil scavenger structure and the outer wall of the bearing chamber. The oil film in the area of the same shear component and gravity direction nearby the oil scavenger structure was thinner, the local heat transfer coefficient was smaller; the oil film in the area at opposite direction was thicker, and the local heat transfer coefficient was larger.