The capability to model an aeroengine internal gearbox in its entirety using CFD is currently hampered by the complexity of the two-phase, highly rotating system and the computational resource required. The University of Nottingham's Technology Centre in Gas Turbine Transmission Systems has developed a representation of a shrouded gear based around a cone geometry with momentum sources driving the flow that works well for single phase flow. The next phase of the study is to investigate the capability and limitations of this momentum source model for two phase flow and a significant step towards this is reported here.In this paper a geometrically representative shrouded gear model is generated and oil droplets are released at key inlet locations. The impact locations of these droplets are mapped to generate data for comparison with the momentum source model. A thin film model is applied such that film build up can be investigated. Droplets entering the shroud at inlet impact towards the lower part of the shroud whereas those introduced at a location representing an into-mesh jet impact more evenly along the shroud. The film model is computationally expensive: computations show film building up towards the top of the shroud but attaining steady state has not been possible.Droplets are released and tracked within the momentum source CFD model. Droplets do not impact the shroud at comparable locations to the representative geometry cases showing that the momentum source representation cannot be used to examine in detail oil behaviour under the shroud. Overall bulk flows cannot yet be compared and further necessary work is identified.
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