Drag scaling law and parachute terminal velocity of the dandelion

Abstract

The common dandelion uses a bundle of drag-enhancing bristles (the pappus) that enables seed dispersal over formidable distances; however, the scaling laws of aerodynamic drag underpinning pappus-mediated flight remain unresolved. In this paper, we find that the aerodynamic drag of dandelion is approximately proportional to the −2/3 power of the dandelion pappus Reynolds number, and the terminal velocity of dandelion seeds is proportional to the 3/4 power of dandelion pappus weight. By the way, the Vogel exponent −2/3 for dandelion is determined.