翼缝是翼型主体与襟翼之间的缝隙，对翼型气动性能与流场结构有很大影响。以两段式NACA0018翼型为基础翼型，对传统弯曲翼缝进行改进设计与数值模拟，以期增大失速攻角及改善在大攻角下的气动性能。结果表明：在小攻角下，导叶翼缝襟翼翼型的升力较原始NACA0018翼型小，阻力较大，但在大攻角下，导叶翼缝可减小翼缝中流体的速度损失，为翼型上表面边界层提供更多动能，从而改善流场结构及失速特性，弯曲翼缝可增大1°失速攻角，而导叶翼缝可增大8°，攻角为18°时升力系数较弯曲翼缝提升43%。因此，导叶翼缝可极大地改善翼型在大攻角下的气动性能。

Gap is the slot between main body and flap which greatly influences aerodynamic performance and small flow structure.Based on the two-element NACA0018 airfoil,for enhancing the ability to rise stall angle and aerodynamic performance of airfoils,the gap configuration was modified and numerically investigated.Results indicate that although modified guide-blade gap configuration leads to lift reduction and drag increase,the ability to delay flow separation was stronger and it decreases the velocity loss in the entrance of gap.The modified guide-blade gap increases the stall angle by 8°,compared to 1°of the original gap.Furthermore,the lift coefficient is increased by around 43%.Thus,the modified guide-blade gap significantly improves the aerodynamic performance of airfoil at high angle of attack.

TK83

国家自然科学基金（51176129，51676131）