Investigating the Route to Flutter in a Pitch–Plunge Airfoil Subjected to Combined Flow Fluctuations

TLDR: In this article, a pitch-plunge airfoil with cubic hardening nonlinearity in the pitch degree of freedom is modeled as a long time-scale random process and the role of noisy flow fluctuations in the same is analyzed by examining the dependency on noise intensity.

Abstract: The dynamics and response a pitch–plunge airfoil with cubic hardening nonlinearity in the pitch degree of freedom are investigated numerically. The aerodynamics is assumed to be linear and modeled using the unsteady aero-dynamical formulation. The flow is fluctuating in both the longitudinal and vertical directions. The fluctuating flow is mathematically modeled as a long time-scale random process. The mean flow speed is used as the bifurcation parameter, and response analysis is carried out by systematically varying the bifurcation parameter. The route to flutter is presented, and the role of noisy flow fluctuations in the same is analyzed by examining the dependency on noise intensity.