Intake Performance Analysis for Extra-Design Variations in Local Flow Field of a Supersonic Aircraft
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Aircraft performance mainly relies on the provision of quality air to its engine. An efficient air intake is always designed to grasp air from free stream flow at a specified mass flow rate with minimum pressure loss and least distortion at the required Mach number. In the same context, the behavior of an air intake in response to variations in its local flow field is vital to accommodate aircraft design optimization / future modification requirements. This study is also aimed at evaluating the intake performance of a supersonic aircraft through variations in its local flow field. Reynolds Average Navier-Stokes (RANS) equation-based analysis of the integrated Diverter less Supersonic Inlet (DSI) was carried out earlier using the Spalart Allmaras (SA) turbulence model, which served as the reference for further evaluations in the present work. A pod with known geometry was utilized as a local flow field variation source, which is already under consideration for future integration on the aircraft considered in this study. After creating the required geometric model comprising aircraft, engine, and pod domain, requisite meshing was performed followed by analysis using Computational Fluid Dynamics (CFD). Intake performance was gauged through total pressure recovery at M=0.8 and M=1.5 by varying the pod locations against four angles of attack (-4 degree, 0 degree, 4 degree, 8 degree) at each pod location. Very less variation in total pressure recovery was observed for subsonic flows. For supersonic flows, considerable variation in total pressure recovery was observed for variable pod locations and angles of attack with relatively lower intake performance at pod locations close to the fuselage.Keywords:
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