Abstract:Porous media materials, due to their unique pore structure, can be used to simulate the permeability characteristics of bird wing feathers. This article takes the NACA0012 airfoil as the research object, covers the surface of the airfoil with porous materials to simulate bird wing feathers, applies the theory of porous media, and explores the influence of permeability parameters on the aerodynamic characteristics of the airfoil through CFD method.The results show that: 1) The semi covered porous airfoil can significantly improve the aerodynamic performance of the airfoil, especially the stall characteristics of the airfoil. The stall angle of attack increases by 2°, and the maximum lift coefficient increases by 16.2%; 2) The permeability characteristic parameters Darcy""s number and porosity have a significant impact on the aerodynamic characteristics of the airfoil. The aerodynamic performance of the airfoil deteriorates with the increase of Darcy""s number and improves with the increase of porosity; 3) Anisotropy has a significant impact on the aerodynamic characteristics of airfoils, among which the anisotropic porous airfoil with high permeability in the y-direction has the best aerodynamic characteristics, which is consistent with the bird wing feather structure. The surface covered porous medium airfoil scheme and its research conclusions adopted in this article can provide a reference for the design and research of bionic airfoil.
