(Downloading may take up to 30 seconds.
If the slide opens in your browser, select File -> Save As to save it.)
Click on image to view larger version.


Figure 3


Fig. 3. Two-stroke flapping motions near the optimum. (A) 1/P* vs {alpha}d for steady motion (black), two-stroke motion composed of a gliding downstroke followed by a vertical upstroke (green), and two-stroke motion composed of the same gliding stroke followed by a near optimal lift-generating upstroke (red). (B) The near optimal down- and upstrokes. Ai, Bi, airfoil NACA2414 at Re~3x105; Aii, Bii, plate at Re~103.