Vortical Flowfield Structure at Forward Swept-Wing Configurations

Extensive aerodynamic investigations have been carried out on forward swept-wing cone gurations with a wing sweep of i 40 deg. A generic wing-body model with removable aft swept canards is used to measure the instantaneous velocities in several crosse ow planes applying advanced hot-wire anemometry. The tests were made at 10-, 20-, and 30-deg angle of attack at a Reynolds number of 0 :46 £ 10 6 . Detailed surveys of mean and rms velocities show that at moderate angles of attack strong wing leading-edge vortices aregenerated rotating opposite in a sense to the wing tip vortices. At higher incidences trailing-edge vortices are shed at the inner-wing part with the same sense of rotation as the wing tip vortices. The canard vortices pass the wing leading-edge relatively high, and after theonset of wing vortices they are moved upward and outboard. Theinterferencebetween these vortices is studied in detail by analyzing the associated turbulent e ow structure. Vortex bursting over the wing occurs already at moderate angles of attack. Downstream, the highest turbulence intensities are found in an annular region around the burst vortex core, where e uctuations are signie cantly channeled into a narrow band.