ABSTRACT
The wings of a supersonic airplane are very different from those of subsonic airplanes or transonic airplanes. The difference is in their appearance, and more importantly in the principle of generation of lift. The air pressure increases when the airflow passes oblique shockwaves, and decreases when it passes expansion waves. Lift can be generated if oblique shockwaves and expansion waves are formed around an aerofoil at assigned locations by design. This chapter describes and analyzes patterns of formation of oblique shockwaves and expansion waves for several possible aerofoil designs. The supersonic airflow around a supersonic aerofoil can be relatively accurately described by an aerodynamic model – a set of mathematical equations and their boundary and initial conditions. Double wedge aerofoil was a popular design for early supersonic flight. The shape of double wedge can be symmetrical or cambered.
