In this paper, aeroelastic equations for a two-dimensional wing encountering a wind gust are
presented and solved numerically. The indicial aerodynamic theory based on Wagner's
function is adopted to obtain aerodynamic forces and moments acting on the wing in the
time domain. The dynamics of the wing is approximated via two degrees-of-freedom, ie pitch
and plunge. The structural stiffness is modeled by a linear translational and a nonlinear
torsional spring. Two different types of stiffness nonlinearities are examined:(i) flat spot or …