一様吹出し制御による翼面摩擦抵抗低減効果の実験的定量評価

抄録

Effects of uniform blowing on an airfoil are investigated experimentally aiming at turbulent friction drag reduction. In order to examine the control effects, velocity measurements on the airfoil by a hot-wire anemometry are conducted. The velocity gradients on the airfoil surface are found to be reduced by uniform blowing, which suggests that local skin friction are suppressed qualitatively. We have also attempted a quantitative assessment of the control effect using the mean velocity profiles in the boundary layer; the modified Clauser-chart method and the method using the law of the wall with pressure gradients. Though these assessments, it is found that these methods are consistent with each other and 21%−66% of the local friction drag are reduced by this control. From these investigations, it is also confirmed that the uniform blowing is effective for friction drag reduction on the airfoil quantitatively.