Fluidic Control of Asymmetric Forces on a Body of Revolution

The aerodynamic steering forces and moments on an axisymmetric bluff body are controlled by exploiting induced asymmetric, segmented attachment of the base flow to a Coanda surface on a circular tail end. Control is effected by an array of four individually-addressable, aft-facing synthetic jet actuators that emanate from azimuthally-segmented slots, equally distributed around the perimeter of the tail. The model is suspended in the wind tunnel by eight thin wires each instrumented with a miniature strain gage sensor for direct dynamic force measurements with minimal support interference with the wake. The aerodynamic effects associated with quasi-steady and transitory asymmetric activation of the Coanda effect are characterized using force and hot wire measurements. Transitory modulation of the actuation waveform of multiple actuators leads to the generation of significant dynamic side forces of controlled magnitude and direction with potential utility for flight stabilization and fast maneuvering. Nomenclature Aj actuator orifice cross-sectional area CL lift coefficien