ON THE AERODYNAMICS OF MOULT GAPS IN BIRDS

摘要: During the moult, birds sequentially replace their flight feathers and thus temporarily have gaps in wings. These will vary size position(s) during course of moult. We investigated aerodynamic effects having moult a rectangular wing by using vortex-lattice (panel) approach, we modelled effect gap at initiation position, position primary tract two simultaneous (as occurs secondary feather moulting many birds). Both had detrimental on performance as measured lift curve slope, effective aspect ratio efficiency wing. The was largest when well inside wing, because circulation declines close to tip. In fact, tip, slightly increased distribution then became closer optimal elliptical distribution. with increasing ratio, which could help explain why large relatively slow rates associated small gaps.