One-degree-of-freedom rotational galloping under strong wind conditions (Q1371526)

The title system needs different treatment for weak and strong wind. The first case can be studied by using a weak perturbation of the mechanical system, and therefore the authors focus their attention on the second case when the perturbed system is analyzed for limit cycles by using Pontryagin's method for perturbed Hamlitonian systems. The authors derive a model equation and prove that wind forces are conservative under certain conditions. Thus the model equation can be considered as an equation which describes perturbations of a wind-velocity-dependent nonlinear Hamiltonian system. The study is illustrated by an example with third-degree aerodynamic coefficient, and by a strong wind analysis for general aerodynamic coefficients.