Experimental and numerical investigations have been conducted on the aerodynamic control and maneuvering of slender bodies at high angles of attack.The study was conducted on an U.S. NAVY countermeasure concept projectile termed GuiDED Missile, and rectangular aftbody strakes were used to control the flow at high angles of attack.Forebody geometries studied include O-give, hemisphere and elliptical geometries.The optimal forebody design was based on maximum strake-induced mean yawing moment obtainable, minimum natural flow asymmetry, and minimum forebody-induced flow oscillation. The results show that the most effective flow control at high angles of attack is achieved with the O-give nose forebody geometry.
For the O-give nose geometry, impacts of various body components including fairings, forebody wings and aftbody fins on the overall control performance were investigated. Effects of strake height, length, axial and azimuthal locations were studied, and an optimal rectangular strake planform was determined. Off-surface flow visualizations were conducted to study the flow fields associated with O-give, hemisphere and elliptical forebody geometries, and the optimal strake in combination with O-give forebody.
Numerical simulations using FLUENT were conducted at low angles of attack for the baseline model with O-give and hemispheric forebodies. Simulations were performed at different Mach numbers for the O-give nose. The results obtained from the simulations were compared to that of the experiments.