为减小流体从吸力面流至压力面的速度损失，基于小间距翼缝有助于减小气动损失的设计原理，针对NACA0021翼型，提出双侧导流式、内导流式和外导流式3种新型翼缝形式。通过数值模拟方法，分析不同翼缝对垂直轴风力机气动性能和流场结构的影响，并将其性能参数与原始翼型和非圆弧翼缝翼型进行对比。结果表明：内导流式翼缝风力机气动性能优于原始风力机，最佳尖速比减小8.06%，改善了叶片周围和整机流场结构，增强了风力机运行稳定性；在低尖速比下，双侧导流式翼缝风力机气动性能较高，而高尖速比时气动性能低于原始风力机；下游区叶片迎风速度较低，外导流式翼缝对流动分离现象改善效果不明显，导致气动性能较差；非圆弧翼缝的间距过大使最大风能利用系数降低了15.5%，不适用于直线翼垂直轴风力机。

Based on NACA0021 airfoil and the design principle of small spacing gaps helps to reduce aerodynamic loss, in order to reduce the velocity loss of fluid flowing from the suction surface to the pressure surface, three new types of flowdeflecting gaps were proposed: TwoSide Flow Deflecting Gap, TowardInside Flow Deflecting Gap and TowardOutside Flow Deflecting Gap. The influences of different gaps on aerodynamic performance and flow field structure of Vertical Axis Wind Turbine were analyzed through numerical simulation.Then the aerodynamic parameters of three new types of airfoils were compared with those of clean airfoil and the airfoil with noncircular gap. The results show that the aerodynamic performance of the wind turbine with TowardInside Flow Deflecting Gap was better than the clean wind turbine and the optimal tip speed ratio decreased by 8.06%, which not only improved the flow field structure, but also improved the operation stability of the wind turbine. The aerodynamic performance of the wind turbine with TwoSide Flow Deflecting Gap was better than the clean wind turbine when the tip speed ratio was low, while the aerodynamic performance of the high tip speed ratio was worse than that of the clean wind turbine. Due to the flow separation phenomenon was not alleviated effectively, the improvement effect of the TowardOutside Flow Deflecting Gap was not obvious, resulting in poor aerodynamic performance. The excessive space of noncircular gap reduced the maximum power coefficient by 15.5%, which was not applicable to straightblade vertical axis wind turbine.

TK83

国家自然科学基金（51676131）；国家自然基金国际(地区)合作与交流项目（51811530315）；上海“科技创新行动计划”地方院校能力建设项目（19060502200）