On a nonlinear behavior of an aeroelastic system with quartic stiffness

This research performs a nonlinear analysis of a typical section airfoil limited to two degrees of freedom emphasizing the evaluation of the effects of a quartic structural stiffness on dynamic responses. Analytical studies are presented based on a simulated model. First, the influence of the quartic term of nonlinear structural stiffness in spring moment is evaluated. Then, phase portraits are presented as a function of freestream velocity, and a time domain decomposition of time histories is performed to identify the limit cycle frequency. Additionally, it maps the region of limit cycle oscillations (LCOs). Furthermore, the aim of this work is to characterize the nonlinear aeroelastic response.