Aeroelastic response of a low-aspect-ratio wing undergoing forced pitching oscillations

Forced pitching oscillations of a low-aspect-ratio (AR = 2) finite wing with a NACA0015 airfoil section are investigated using high-fidelity large-eddy simulations at a Reynolds number (Re) of 50,000. At this Re, the boundary layer transitions from laminar to turbulent on the suction surface, forming a laminar separation bubble (LSB)—a key feature in high-Re aerodynamic behavior. We study how the reduced velocity and the location of the rotational axis influence the energy transfer mechanisms that drive flutter. A moment partitioning method is employed to identify the specific vortical structures responsible for flutter-inducing aerodynamic moments. The flow field and wingtip vortices are analyzed to understand their role in the aeroelastic response. In parallel, we examine how the LSB forms, evolves, and bursts during pitching cycles, providing new insight into its interaction with unsteady aerodynamic loading. Preliminary studies on free pitching oscillations are also carried out and compared with corresponding forced oscillation cases.