Evaluation of the Volume of Fluid Modelling Approach for Simulation of Oil/Air System Flows

In recent years, improvements in computing hardware and numerical methods have provided the means for aero-engine manufacturers to use CFD to undertake air system analyses in ever-increasing detail. The main benefit of this work is that it has provided both qualitative and quantitative insights into air system performance and design practices that were not previously accessible by other means. With continued improvements in computing technology virtually assured to the end of the decade, it is logical to expect that the technological advances made in air systems analysis will be extended into the more complex two-phase applications — such as those found in the oil systems of aero-engines. In the present work a number of two-phase volume of fluid (VOF) applications are presented, in situations likely to be encountered in an aero-engine oil system. Some of these applications represent generic test cases, whilst others are direct applications to actual engine components. It is evident from the results presented that considerable understanding and insight can be gained from the application of CFD techniques in these two-phase regimes and that with care these methods can be used to guide two-phase design methods.