Wake Turbulence Structure Downstream of a Cambered Airfoil in Transonic Flow: Effects of Surface Roughness and Freestream Turbulence Intensity

[摘要] The wake turbulence structure of a cambered airfoil is studied experimentally, including theeffects of surface roughness, at different freestream turbulence levels in a transonic flow. As thelevel of surface roughness increases, all wake profile quantities broaden significantly and nondimensionalvortex shedding frequencies decrease. Freestream turbulence has little effect on thewake velocity profiles, turbulence structure, and vortex shedding frequency, especiallydownstream of airfoils with rough surfaces. Compared with data from a symmetric airfoil, wakeprofiles produced by the cambered airfoils also have significant dependence on surfaceroughness, but are less sensitive to variations of freestream turbulence intensity. The cambered airfoil also produces larger streamwise velocity deficits, and broader wakes compared to thesymmetric airfoil.

[学科分类] 力学，机械学