Aerodynamic characterization of leading-edge tubercles bionic airfoils with different configurations at high Reynolds number

Leading-edge tubercles have consistently been a key focus in aerodynamic biomimetics. A leading-edge tubercled wing model, based on the ONERA (Office National d'Études et de Recherches Aérospatiales) M6 wing, was examined at high Reynolds numbers to analyze the effects of the tubercles. First, six distinct parameter configurations were employed to analyze the aerodynamic characteristics of the tubercled wing, comprising three conventional single-equation configurations and three modified two-equation superimposed configurations. Numerical results indicate that the tubercled wing exhibits reduced performance at low angles of attack but improved performance at high angles of attack. Among the tested configurations, the single-equation model A06R26 achieved the best performance, with a maximum lift coefficient increase of 16.7% and a maximum lift-to-drag ratio improvement of 9%. Subsequent analysis, including shock vortex plots, reveals that the tubercled wing generates localized shocks at the troughs of the tubercles and causes early airflow separation at low angles while suppressing separation at high angles. Additionally, surface flow analysis reveals two primary flow modes on the surface of the tubercled wing at high Reynolds numbers, which are the main contributors to its superior performance. Finally, the performance of the tubercled wing configured with a single-equation model is compared to that of a two-equation model. The analysis shows that integrating advantageous configurations from the single-equation model into the multi-equation model allows the latter to inherit favorable performance characteristics, such as lift-to-drag ratio. This provides valuable recommendations for the continued development of tubercled wings in complex and realistic scenarios.