Inviscid-Viscous Interactions of Compressible Convex Corner Flows
Variable camber concept, such as deflection of flaps or ailerons in cruise, could play a role in performance optimization for current- and future-generation aircrafts. Within the operational flight envelopes, it would change the flowfield and consequently modify aerodynamic characteristics. A study by Szodruch and Hilibig also indicated that variable camber can be employed to improve the transonic maneuvering characteristics of a fighter aircraft. Furthermore, Parndtl-Meyer expansion is well known in supersonic flows. However, the subsonic expansion or transonic expansion flows around a sharp convex corner are less studied. At lower Mach number, the flow is expanded and recompressed around a sharp corner. With increasing Mach number or convex-corner angle, the boundary layer is subject to a rapid acceleration and the flow switches to transonic expansion flow. Noted that Chung proposed a similarity parameter to characterize the flowfield, in which the transition of subsonic and transonic expansion flows is observed at M 2 η=6.14. Shock-induced boundary layer separation is also another concern for application of variable camber concept.
KeywordsMach Number Sharp Corner Stagnation Pressure Lower Mach Number Freestream Mach Number
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