Aerodynamic Performance and the Associated Flowfield during Dynamic Motions

An swept and tapered wing was investigated experimentally undergoing static and dynamic motions, exploring the effect of pitch, roll, and yaw at mean chord-based Reynolds number of 250,000. The wing has a taper ratio of where the trailing edge is swept forward 30deg and leading edge is unswept. The results obtained for this wing were compared to those of a cantilevered semi-span wing with the same geometry. The effect of static yaw and roll on the aerodynamic performance of the wing was also explored. It was found that roll has small effect on the lift, drag, and pitching moment, whereas yaw largely impacts the aerodynamic forces due to large asymmetric flow structures that form on each side of the wing. Sinusoidally pitching motions showed that the pitch rate plays a significant roll in the size of the hysteresis loops, the maximum lift, and maximum drag. Ramp-up/ramp-down pitching motion was also explored and showed transitory behavior during the onset of ramp-up and ramp-down. These transients are likely influenced by the change in acceleration at the onset and conclusion of the motion. These ramp-up and ramp-down motions were compared to the sinusoidally pitching motions and found that the ramp-up/ ramp-down motions observe a second order like response compared to their sinusoidal counterparts.