Aerodynamic Behavior of a Biomimetic Wing in Soaring Flight – A Numerical Study

Abstract

Multi-element wing tips based on bird wings appear attractive in soaring flight, where a minimal sink velocity is the design goal. The present study aims to reproduce the soaring flight observed from white storks (ciconia ciconia) in a biomimetic computational model in order to visualize and investigate the flow around and through the wing tip cascade. RANS and hybrid RANS–LES computations have been performed allowing access to all features of the flow field. The resulting properties in soaring flight have been compared to measured data of free flying birds from the literature to qualify the results of the re-engineered wing. Further, the flow field has been analyzed in detail to understand the underlying flow physics and to point out relevant phenomena such as a system of vortices associated with the wing and tip design which contributes to the observed aerodynamic properties.