The hemisphere-cylinder in dynamic pitch-up motions

Laser-Doppler velocimetry and seven-hole probes were employed to map out the velocity and vorticity field along a plane downstream of a hemisphere-cylinder. Steady flow data were obtained over a fixed model at a range of angles of attack, as well as over a model pitching through ramp motions to a final angle of attack. Attention was focused on the dynamic development of induced vortex asymmetry. It was found that the wake develops first in a symmetric fashion and asymmetry is generated with some time delay.