You are here

Drag Reduction of Rotorcraft Fuselage

Separation control of the 3-D flow over the aft body of a scale model of NASA’s ROBIN mod7 rotorcraft fuselage is investigated in wind tunnel experiments using successive pulsed actuation effected by arrays of miniature combustion-based actuators.  The actuation leads to the formation of momentary jets having a characteristic time scale O[1 ms] that is an order of magnitude shorter than the convective time scale of the flow.  These actuators are placed upstream of the transition region between the fuselage and the tail boom, and their interactions with the massively separated cross flow in this domain and, consequently, their effects on the global aerodynamic forces and moments are investigated using an onboard load cell and measurements of the velocity field using high resolution PIV that is acquired phase-locked to the actuation waveform.  Symmetric actuation about the model’s centerline can significantly mitigate separation, and lead to a reduction in drag and lift, and changes in the pitching moment.  Asymmetric actuation, and consequently non-uniform attachment can induce large side forces, roll and yaw that can be exploited for steering and improved flight maneuverability.

Supported by NASA