RT Journal Article ID 5db9c46768bd32c7 A1 Sooraj, P. A1 Agrawal, Amit T1 FLOW AROUND A CORRUGATED AIRFOIL JF Journal of Flow Visualization and Image Processing JO JFV YR 2018 FD 2018-12-07 VO 25 IS 3-4 SP 145 OP 162 K1 corrugated airfoil K1 particle image velocimetry K1 flow separation AB The flight of a dragonfly, similar to many insects and small birds, is very much determined by the corrugation on its wings. A particle image velocimetry (PIV)-based study is conducted here on a rigid corrugated wing for a Reynolds number (Re) of 300-12,000 to better understand the mechanism of dragonfly flight. Two different angles of attack (5° and -5°) are considered in the study. This is perhaps the first flow visualization study using PIV where flow around a corrugated airfoil at a negative angle of attack has been explored. It is found that the shape of the corrugation plays an important role in producing vortices. Bigger vortices are observed at the -5° angle of attack compared to that of +5°. Also the shedding of vortices starts at lower Reynolds numbers for -5°. The vortices grow in the valleys of corrugation for a while before shedding; the frequency of shedding from a valley is half that for its immediate upstream valley. The vortices trapped in the valleys dictate the shape of the virtual airfoil formed around the corrugated wing. It is also found that the shape of the virtual airfoil formed around the corrugated sheet is similar to that of Prandtl-D root-ns airfoils. PB Begell House LK https://www.dl.begellhouse.com/journals/52b74bd3689ab10b,0a83c7b6324209cb,5db9c46768bd32c7.html