Airfoil Aerodynamics in Proximity to Wavy Water Surface

The aerodynamics of the airfoil National Advisory Committee for Aeronautics (NACA) 4412 moving in proximity to a wavy water surface are investigated using numerical methods, and the conditions under different values of the Reynolds numbers and Froude numbers are investigated. The aerodynamics of the airfoil over a wavy water surface are compared with those pertaining to rigid wavy ground. The results show that the aerodynamic coefficients for the wavy water surface are significantly different than those for rigid wavy ground. The changes in the Reynolds number and Froude number considerably influence the aerodynamics. The analysis of the flow field shows that the flow mechanisms of the airfoil moving over the wavy water surface and rigid wavy ground are significantly different. The particles on the wavy water surface and wavy ground surface exhibit a vertical and horizontal velocity, respectively. The analysis of the flow mechanism clarifies the reasons for the different aerodynamics under the two boundary conditions. This study has a certain guiding significance for the design and realization of safe flight of wing-in-ground crafts.