Computational Investigation of Vortex Breakdown over a Pitching Delta Wing at Supersonic Speeds

Abstract

Vortex breakdown in compressible flows over a 60-degrees sweep delta wing with a sharp leading edge undergoing pitching oscillations is computationally studied. Emphasis in this study is on possible supersonic vortex breakdown for pitching motion of a delta wing, as well as aerodynamic characteristics behavior during a cycle. Unstructured grid, turbulence model and dual-time implicit time integration are used. Accurate simulations are performed for various Mach number and mean angles of attack to cover different flow structures and phenomena associated with them. Variations of flow structure around the wing and hysteresis loops associated with lift coefficient and vortex breakdown location during a pitching cycle are investigated. The trends with Mach number, mean angle of attack, amplitude of pitching and pitching frequency are illustrated.