PIV Study of Conical Forebody Flow Control Using Plasma Actuators

Duty cycle modulation of the alternate blowing from two opposite facing plasma actuators on the leeward surface near the apex of a cone having semi-apex angle of 10° to control the mean lateral force, moment and the flow control mechanisms are presented. The pressure distributions over the cone forebody are measured using steady pressure-tappings. The flowfields are visualized by a two-dimensional particle image velocimetry (PIV). The experiments are performed at 5m/s wind speed with Reynolds number 40,000 based on the cone base diameter. The opposite bi-stable vortex patterns appear when the port or starboard actuator is activated while the other is kept off during the test. The phase-locked (locked to the plasma duty cycle) averaged vertex cores controlled by the duty-cycled plasma actuation are periodic and vary around the position of the ensemble averaged vertex cores.