Unsteady Aerodynamics on a Low Aspect Ratio Flat Plate Available to Purchase

The study of biological flight has shown the potential of using unsteady fluid mechanism to enhance lift and drag capabilities in low Reynolds number flight regimes. To help further the knowledge of unsteady aerodynamic fluid phenomena, a low aspect ratio flat plate is subjected to a pitching motion superimposed on a plunging motion. Variations in this motion are introduced by adding a phase lag to the pitching cycle relative to the plunge cycle. Particle Image Velocimetery (PIV) is used to measure the instantaneous velocity fields over the upper surface of the flat plate at several points in the motion cycle. These vector fields are then averaged over approximately 420 ensembles to obtain the mean velocity field at the points in the cycle. Three vortex detection algorithms are implemented to identify the center of the vortex structures created off the leading edge and track their convection downstream. Experiments show that phase lags between 75° and 90° are more prone to create organized vortex structures and convect them in close proximity to the upper surface of this low aspect ratio flat plate.