Contribution of spanwise and cross-span vortices to the lift generation of low-aspect-ratio wings: Insights from force partitioning

Abstract

A novel force-partitioning method is used to quantify the lift induced on finite-span wings at low Reynolds numbers by streamwise and spanwise oriented vorticity over the wing and in its wake. Although spanwise vortices, such as the leading-edge vortex, are thought to be the dominant lift producing mechanism, we show that streamwise vorticity induces a higher net lift on the wing and spanwise vorticity in the wake can produce negative lift. We quantify the lift induced by vortex cores and their associated strain-dominated flow, and show that they exhibit very different vortex tilting and stretching dynamics that can diminish the influence of spanwise and augment streamwise vorticity.

Topics & Concepts