A numerical study on smart material selection for flapped and twisted morphing wing confgurations

Abstract

© 2014, Journal of Aerospace Technology and Management. All Rights Reserved.The developments of innovative adaptive structures on Unmanned Aerial Vehicles (UAVs), such as morphing wings, can potentially reduce system complexities by eliminating control surfaces and their auxiliary equipment. This technology has the potential of allowing a UAV to adapt to different mission requirements or to execute a particular mission more effectively by maintaining an optimum airfoil section over a range of speeds for different segments of a mission profle. Studies on a number of smart materials candidates are currently available in the open literature to achieve wing morphing. The material selection depends on several factors including fast dynamic response, low weight, capability to operate over a wide range of fight conditions and low power consumption. This paper presents a review on smart materials technologies for UAV morphing wings. A numerical study in terms of power requirements is also presented for two morphing wing concepts: fapped and twisted wing planforms. The energy calculations for both morphing confgurations were based on a two-step procedure. The frst step consists of computing the aerodynamic energy using an in-house Vortex-Lattice (VL) based program. Subsequently the pressure feld obtained from the frst step is then mapped into a fnite element mesh and the structural strain energy is calculated. The numerical results indicated that fapped morphing wings have a better aerodynamic performance when compared to twisted wings and different morphing levels can be achieved using lighter smart materials with lower specifc energy for this confguration.

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