The Influence of the Reynolds Number on the Auto-Rotation of Samaras

As samara seeds fall from trees, they enter into auto-rotation. In this way they maximize dispersal distances (Green, Am J Bot 169:1218–1224, 1998, [2]). In this study, we present direct numerical simulations of the autorotation of a model samara at Reynolds numbers, Re, somewhat smaller than those observed in nature. The aim is to detect the presence of a LEV, if it exists, and to understand how the kinematics of the seed are related to the vortical structures of the flow.