A numerical model for unsteady oil film motion in aero-engine bearing chambers and experimental verification

The work presented here focusing on the motion of oil film heat and mass transfer. A complete mathematical model based on theoretical study to solve three-dimensional unsteady oil film motion was established. Numerical simulation for different test rigs (bearing chamber test rig of Karlsruhe Institute of Technology (KIT) and rotating cylinder test rig of Northwestern Polytechnical University (NPU)) and different working conditions was carried out by using CFD commercial software. Particle tracks, oil film thickness change history and film stripping were studied, and the numerical results of oil film thickness were obtained. The numerical results show that the motion of the oil film will reach the state of basic stability for unsteady oil flow, and a development process from the oil film formation to basic stability in this paper is less than 1.5 seconds. Moreover, comparison between the numerical results and the experimental values shows that the maximum error of oil film thickness is less than 7% at the measurement points under the calculation conditions, which indicates the proposed computational model to solve unsteady oil film motion is a valuable technical means for the study of oil film movement mechanism and oil film heat and mass transfer.