Effect of Damping on Bifurcation and Synchronization Behavior of an Aeroelastic System Under Dynamic Stall

The present study aims to investigate the effect of damping on the bifurcation characteristics of a pitch–plunge aeroelastic system subjected to dynamic stall-induced aerodynamic nonlinearities. It is observed that structural damping has a considerable impact on both the bifurcation boundaries and the response dynamics. To understand the physics behind the altered response dynamics, a synchronization study is undertaken next. The synchronization characteristics are identified through phase-locking value (PLV) under different values of plunge (ζξ) and pitch (ζα) damping ratios. The phase locking of the plunge and pitch modes is demonstrated to be significantly affected by increasing the values of plunge and pitch damping. It is demonstrated that increasing the damping in pitch enhances synchronization by increasing the PLV. Additionally, stall flutter is delayed in the presence of pitch damping. The increase in plunge damping leads to the early onset of the synchronization regime leading to the early onset of stall flutter. The combined effect of the two damping leads to delayed onset of both aperiodic as well as stall flutter regimes.