Wingtip Vortex Alleviation Using a Reverse Delta Type Add-on Device

<p>The result of interactions of a wingtip vortex of a half-span wing and vortices generated by a slender reverse delta type add-on device were studied using Particle Image Velocimetry in a closed-loop low-speed wind tunnel. Characteristics of the vortex interactions produced downstream in planes perpendicular to the free stream direction at a mean chord-based Reynolds number, <em>Re_c = 2.75×10⁵</em>, are explored in this work. The study reveals that the reverse delta type add-on device considerably reduces the tangential velocity, vorticity and circulation magnitude of the resultant vortex by up to 79.6%, 85.6% and 48.7%, respectively. It was also found that the resultant vortex core radius increased by a factor of 5.63. Using a six component force balance, the reduction in lift and the increase in drag of the half-span wing with the reverse delta type add-on device was recorded to be 2.9% and 14.5%, respectively.</p>