Flow Field and Loading Analysis on a Wrap-Around Fin Missile

摘要

Wrap-around fin (WAF) missiles offer packaging benefits but experience rollingmoments due to the curved fin design. Rolling moments stabilize unguided projectiles, but cause guidance and control problems for future guided applications. Understanding the flow field in the vicinity of the fins is critical to future missiles. Fin pressure profiles were characterized with pressure-sensitive paint. Two rectangular four-fin constructions were tested-one solid and one with a rectangular hole (slotted fin). Static pressure data were divided by free-stream total pressure for presentation. Tests were conducted at Mach numbers of 2.15, 2.28, 2.41, 2.86, 3.25, 3.50 and 3.83. Reynolds numbers based on missile diameter ranged from 4.0 x 106 to 1.3 x 10(7). Mach 2.86 pressure profiles on the solid fin were compared to computational fluid dynamic (CFD) predictions on a single wall-mounted fin. The four-fin model pressure distributions agreed with CFD, verifying that a single wall-mounted fin captures relevant WAF aerodynamics. Slotted fin pressure profiles were similar to solid fin profiles, except in the vicinity of the slot.