On the response of a flexible freely flying wing to an isolated vortex gust

Vortex gusts have significant effects on the flight dynamics of aircraft, and as modern aircraft become smaller, lighter, and more maneuverable, the negative effects of these flow disturbances have become an increasingly important issue. In this study, the dynamic response of a rigid wing "flying" with two degrees of freedom (pitch and plunge) subjected to vortex gusts, is studied experimentally and through CFD simulations. Single coherent vortex gusts of desired strength, sign, and location are generated through an upstream wing through a combined heave and pitch maneuver. The downstream wing is experimentally controlled using a cyber-physical system (CPS), which allows it to react realistically to vortex gusts. We assess the dynamics of the wing during gust encounters by using a modified formulation of the classical thin airfoil theory, with which we describe the behavior of the wing when subjected to a vortex gust. We present comparisons between experimental, CFD simulations, and analytical results, and we comment on the impact of these encounters on the stability of the wing. Finally, we discuss the effects on the dynamics of subjecting a flexible wing to these vortex gusts.