FLOW PHYSICS OF CRITICAL STATES FOR ROLLING DELTA-WINGS

A delta wing rolling at high flow inclination has two well-documented critical states. One occurs when the breakdown of the leeside leading- edge vortex passes over the trailing edge, and the other when the brea kdown of the windward vortex reaches the apex. The flow physics associ ated with those critical states are described for a sharp-edged 65-deg delta wing rolling around an axis inclined 30 deg to the freestream. It is shown how the measured, extremely nonlinear, unsteady aerodynami cs result from the roll-rate-induced camber effect in conjunction with convective flow time lag effects.