An experimental investigation was conducted on the flow field surrounding a delta wing undergoing a transient pitching motion. The location of the leading edge vortices over the surface of the wing was studied. This investigation was conducted on a 70 deg sweep, flat plate delta wing pitched about its one-half chord position. The transient motion of the wing was obtained by pitching the model through half a cycle of sinusoidal motion. The wing was pitched using a range of pitch rates, and at Reynolds number based on root chord between 83000 and 373000. The leading edge vortex cores were marked with smoke and the model and vortex motions were recorded using high speed motion pictures. These films were then analyzed to yield information on the vortex location and trajectory as functions of both angle of attack and time. The position of vortex breakdown for the transient motion was seen to lag the location for the static case. The size of the lag increased with increasing pitch rate for a constant Reynolds number. The lag was unaffected by changing Reynolds number for a constant pitch rate. Upon completion of the model motion, the vortex breakdown continued to move towards the static position.
The separated flow field on a slender wing undergoing transient pitching motions
Das getrennte Stroemungsfeld an einem schlanken zeitweilig kippenden Tragfluegel
AIAA-Papers ; Jan ; 1-14
1989
14 Seiten, 22 Bilder, 1 Tabelle, 11 Quellen
Conference paper
English