M.R. Amoozgar, S.A. Fazelzadeh, H. Haddad Khodaparast, M.I. Friswell, J.E. Cooper
DOI Number: N/A
Conference number: IFASD-2019-046
In this paper, the aeroelastic instability of a curved wing is investigated. The wing structure is modeled by using the geometrically exact fully intrinsic beam equations, and the aerodynamic loads are simulated through the incompressible unsteady aerodynamic model. The wing is considered to have initial out of plane curvature, and the effect of the curvature on the flutter speed and frequency of the wing is determined. Two curved wing case studies are considered here. In the first case, the span of the wing is assumed to be constant and therefore as the wing is curved the projected area of the wing decrease. In the second case, the wing is assumed to have a constant projected area and therefore different curvature angles result in different span lengths. When the initial curvature is added to the wing, the dynamics of the wing changes, and therefore the aeroelastic stability of the wing is also affected. It is shown that when the initial curvature of the wing increases, at first the flutter speed decreases and then increases and finally a sudden jump occurs in the flutter speed due to the change of coupled modes contributing in flutter. Moreover, the flutter frequency also first decreases by increasing the curvature of the wing, and then there is a sudden jump in the frequency, and from this point again the frequency decreases. Finally, results highlighting the importance of the initial curvature of the wing on the flutter speed and frequency of these two case studies are presented.