Fig. 4

Experimental set-up for a the spanwise flow measurements and b the LEV circulation growth measurements. In both cases, the laser sheet plane is parallel to the camera, however in the first case (a), the laser-sheet is centered with the axis of rotation; while in the second case (b), the laser-sheet is centered with the spanwise location of interest. The high-speed camera also captures the velocity fields of the flow for different planes of interest. To measure the spanwise flow, the velocity fields are captured when the rotating wing is parallel with the camera’s plane; and to compute the circulation, the velocity fields are captured when the rotating wing is perpendicular with the camera’s plane