Influence of gas entrained in lubricating oil on flow characteristics of rotary plate pump in aviation engine lubricating oil system

The safe and reliable operation of the oil pump is crucial for the normal functioning of an aviation oil system and the safe flight of an aircraft. The rotary plate pump (RPP) is an excellent choice for aviation engine oil systems due to its stable operation, minimal flow pulsation, high efficiency, and compact structure. However, the impact of gas entrainment in the inlet oil on the flow characteristics of the RPP is not well understood, which hinders its application in engine oil systems. In this study, we aimed to investigate the effect of gas entrainment in lubricating oil on the performance of an RPP using numerical simulation. The results obtained from the simulation closely match the experimental results. We were able to determine the influence of the inlet gas volume fraction (IGVF) on various aspects of the RPP, including the flow field characteristics, oil suction and discharge properties, and outlet pressure pulsation characteristics. Our findings indicate that as the IGVF increases, the gas content in the pump chamber also increases, eventually leading to phase separation. This phenomenon results in higher flow pulsation at the outlet of the RPP, a significant decrease in volumetric efficiency, poorer oil suction and discharge performance, and longer periods of pressure pulsation at the outlet. By providing a deeper understanding of the gas-oil two-phase flow characteristics in an RPP, our research contributes to the design and selection of lubricating oil pumps.