Aeroelastic prediction in transonic buffeting flow with data fusion method

The frequency locking in phenomenon will occur in the transonic buffeting flow of the elastically supported airfoil. This phenomenon is usually accompanied by a large oscillation of the structure, eventually leading to the fatigue damage of the structure. Transonic aeroelasticity research based on computational fluid dynamics is extremely time-consuming. At present, the research on nonlinear aeroelastic reduced-order models attracts attention due to its important role in nonlinear limit cycle oscillation amplitude prediction. However, the training process of current nonlinear aeroelastic reduced order model requires massive smooth amplitude-modulated pseudo-random binary signals (SAPRBS), which limits its application in engineering field. This paper proposes a nonlinear aeroelasticity reduced-order model based on the saturated limit cycle oscillation signals (Harmonic Signals) that can be directly obtained in engineering field, providing a new perspective for nonlinear reduced-order models. The model only uses harmonic signals at three frequencies to accurately predict limit cycle oscillation amplitudes within a wide range of the NACA0012 transonic buffeting frequency-locking region. In addition, the model still maintains a certain generalization ability at the extrapolated frequency points.