Investigation of Effects of Nose Bluntness and Angle of Attack on Slender Bodies in Viscous Hypersonic Flows

Hypersonic flows over cones and straight biconic configurations are calculated for a wide range of free stream conditions in which the gas behind the shock is treated as perfect. Effect of angle of attack and nose bluntness on these slender bodies in air is investigated extensively. The numerical procedures are based on the solution of complete Navier-Stokes equations at the nose section and parabolized Navier Stokes equations further downstream. The flow field variables and surface quantities show significant differences when the angle of attack and nose bluntness are varied. The complete flow field is thoroughly analyzed with respect to velocity, temperature, pressure and entropy profiles. The post-shock flow field is studied in detail from the contour plots of Mach number, density, pressure and temperature. Flow separation is observed on the leeward plane for an on-axis, 12.84°/ 7° (fore-cone and aft-cone angle) biconic geometry at 12° angle of attack. Also, the windward and leeward heating rates for the fore-cone section decreases by a factor of four and by a factor of five respectively, when the nose bluntness is increased by an order of magnitude. The effect of nose bluntness for slender cone persists as far as 200 nose radii downstream.