The primary objective of this research was to develop a definitive theory on the cause of wing rock. The study was based on dynamic measurements in both a water tunnel and a wind tunnel on a sharp-edged delta wing with an 80;The initial phase of the study validated ExpertVision accuracy using stationary and forced oscillation tests on 70;Wing rock is caused by the dynamic behavior of the leading-edge vortices. Specifically, the alternate lift-off and reattachment of the vortices generate an asymmetry in vortex lift and cause changes in rolling moment that initiate and sustain roll oscillations. Since wind tunnel and water tunnel tests showed opposite direction hysteresis loops, it was concluded that roll damping could not be the primary aerodynamic mechanism that sets the limit on roll amplitude.;Wing rock dynamics were significantly different between water tunnel and wind tunnel experiments. Apparent mass terms must be included in the equations of motion when converting water tunnel acceleration data to rolling moment coefficients; with no apparent mass correction, C
展开▼
