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Liquid ring pumps are used in aircraft fuel systems in conjunction with main impeller pumps. These pumps are used for priming the pump system as well as to remove fuel vapor and air from the fuel. Prediction of cavitation in liquid ring pumps is important as cavitation degrades the performance of these pumps and leads to their failure. As test based assessment of cavitation risk in liquid ring pump is expensive and time consuming, recent approaches have been to assess and predict the risk of cavitation using Computational Fluid Dynamics (CFD) methods with the goal to quicken the design process and optimize the performance of these pumps. The present study deals with the development and assessment of a CFD methodology to simulate cavitation for a liquid fuel pump used in aircraft fuel systems. The study simulates the cavitation phenomena using a multi-phase flow model consisting of fuel vapor, air, and liquid fuel phases.

There has been an increased interest in low speed aerodynamics for Unmanned Aerial Vehicles (UAVs) and Micro Aerial Vehicles (MAVs). These vehicles which are increasingly being used for reconnaissance purposes operate in the Root Chord Reynolds number range of 104 to around 105 and thus, the flow regime encountered is in the low Reynolds number transitional flow range. Computational Fluid Dynamics (CFD) methods which employ eddy viscosity based RANS turbulence models that are formulated for high Reynolds number flow are not well suited for such low Reynolds number range as they cannot accurately model the formation of laminar separation bubble and subsequent onset of transition. In this paper, the transition k-ω SST model is assessed for aerodynamics prediction for the SD7003 airfoil for Reynolds number ranging from 104 to 9 × 104 and angle of attack ranging from 0° to 8°. The assessment is carried out against available experimental and Large Eddy Simulation results.