GUST LOAD ALLEVIATION OF A TWO DIMENSIONAL NONLINEAR WING USING NONLINEAR ENERGY SINKS

In this paper, the effect of a nonlinear energy sink (NES) device on the aeroelastic and gust response of an aircraft wing with a hardening stiffness structural nonlinearity is investigated. The structural dynamics of the wing is simulated using a 2-DOF typical section which undergoes pitch and heave (plunge) motions. Furthermore, the wing is subjected to a combination of aerodynamic and gust loads. The aerodynamic loads are simulated using Wagner’s unsteady aerodynamic theory, while the gust loads are calculated by assuming two different gust profiles, e.g. sharp-edged and 1-cosine gust profiles. The NES is composed of a mass which is attached to the wing through a nonlinear spring and a linear damper, and its capability on absorbing energy is investigated. First, to verify the developed aeroelastic model, the results are compared with those available in the literature and a very good agreement is observed. Then, the effects of various NES and system parameters on the aeroelastic response of the wing are investigated. The results indicate that by properly designing the nonlinear energy sink, both aeroelastic and gust responses of the wing can be reduced.