View Video Presentation: https://doi.org/10.2514/6.2021-2515.vid

The geometry of the wing planform is key in ascertaining the maximum aerodynamic performance of aircraft and especially so for unpowered variants such as sailplanes. The current work attempts to elucidate the preliminary flow-field characteristics of planar elliptical and crescent-shaped wing planforms at Reynolds numbers corresponding to those of small scaled unmanned aerial vehicles. Representative aerodynamic models are subjected to wind tunnel testing for experimental observation of wake structures through stereo particle image velocimetry. Two case studies are conducted at 2c_bar and 5c_bar for Re= 1 x 10^5, and at 5c_bar for Re = 1.5 x 10^5, to determine changes associated with downstream location and Re variance. Axial vorticity contours of each wing planform’s tip vortex are compared and contrasted with consideration of influencing flow physics. Proper orthogonal decomposition analysis was performed on the cross-flow velocity components associated with the first case study to reveal the most energetic flow field structures followed by reconstruction of the first mode contours.