Computational investigation of vortex structure and breakdown over a delta wing at supersonic pitching maneuver

摘要

Unsteady compressible flows over a 60 degrees swept delta wing with a sharp leading edge undergoing pitching maneuvers are computationally studied. Emphasis in this study is on possible supersonic flow structures and vortex breakdown during the pitching motion of a delta wing. Unstructured grid, k-omega SST turbulence model and a dual-time implicit time integration were used. Accurate simulations were performed for various Mach numbers, initial and final angles of attack, and pitch rates to cover different flow structures and phenomena associated with them. The contours obtained by the numerical results which show the flow structures were compared with experimental visualization images. Variations of flow patterns, pressure coefficient on the wing surface, and the lift coefficient during a pitching maneuver are investigated. Vortex breakdown was observed for both subsonic and supersonic flows and its impact on the lift coefficient during the motion was shown.