Aerothermodynamics of a blunt airfoil with a flow-through duct for hypersonic flight

Abstract

The problem of aerodynamics heating must be resolved to ensure safety of passengers with reduced drag for commercial feasibility of civil hypersonic fights. The aerothermodynamics of a conceptual blunt symmetric airfoil with a circulation enhancing flow through duct is investigated numerically with an unstructured Navier-Stokes Solver. The rectangular duct of slightly diverging cross sectional area makes the flow to enter into the airfoil from the lower surface near the leading edge and comes out of the airfoil at a point on the lower surface near the trailing, following a circular path. The travelling of air in a circular path increases the circulation about the airfoil and the leakage of high pressure air through the airfoil also decreases the pressure drag of the body resulting in high lift-to-drag ratio for the airfoil. The width of the flow-through duct housed inside an airfoil of 1 m chord, increases smoothly from 20 mm at the inlet to 30 mm at the exit. Two dimensional steady state solutions are obtained for a Mach 6 flow of air with static pressure and temperature of 16066 N/m2 and 216.65 K respectively. This paper discusses the feasibility of using a duct to enhance the aerodynamic efficiency of blunt airfoils at hypersonic speeds. The surface heat flux, aerodynamic drag and lift at various angles of attacks for a blunt airfoil with and without duct are presented in this paper.