Bifurcation Characteristics of Airfoil-NESs coupled System

Abstract

Abstract Aeroelastic instability has become a hot research topic. It has increasingly high-lighted its importance in the aircraft and fluid machinery industry and brings challenges to the safe flight of various aircraft and the safe operation of fluid machinery. Numerical simulations were performed to study the flow-induced oscillation of a two-dimensional airfoil with two non-linear energy sinks (NES). The main system has two degrees of freedom-pitch and heave. These two NESs are considered as subsystems, with the first NES at the leading edge and the second NES at the trailing edge. The bifurcation behaviour and the mechanism of the system leading to chaos of the coupled system under different parameters and initial conditions is studied by nonlinear analysis, and the relationship between large amplitude limit cycle oscillation and the chaotic occurrence point of the main system is revealed, this corresponding relationship has important theoretical significance for mastering and adjusting system parameters to make NES work within its ideal oscillation suppression parameters.