Effects of structure parameters of scavenge sump on oil/air two-phase flow in bearing chamber
1. College of Energy and Power Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016, China; 2. Jiangsu Province Key Laboratory of Aerospace Power System, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016, China; 3. Ministry of Industry and Information Key Laboratory of Thermal Environment and Structure in Aero Engine, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016, China
Abstract：To solve the difficulty of oil scavenge and cooling in bearing chamber of aero-engine, the scavenge sump was improved. The effects of the sump structure parameters on oil residence volume fraction (φR), scavenge ratio and convection heat transfer coefficient of the wall were investigated by the volume of fluid (VOF) method in CFD software. The numerical simulation shows that with the increasing of shaft speed, the oil scavenge ability of bearing chamber is decreased, and the heat transfer ability of the wall surface is increased gradually. With the increasing of sump width, φR is decreased with latter rising, while the scavenge ratio is increased monotonously. φR is decreased， and scavenge ratio tends to increase with the increasing of sump depth. Compared with the basic model, the narrow sump (w=1.0) and the shallow sump (h=1) can effectively improve the heat transfer capacity of the wall surface. Appropriate adjustment of the sump position can improve the oil scavenge and heat transfer performance.
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2019, Vol. 40 
