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摘要:
翼型失速问题是风力机设计过程中需要重点考虑的气动现象，而引起失速的主要原因是附面层内流动能量不足，无法提供足够的附着力。利用翼型内部开槽，将大迎角状态时翼型下方的高动量气流引射进上部分离区可以有效解决这一问题。为了设计出具有更好气动特性的开槽翼型，研究了在不同宽度下2种不同形状的开槽对翼型气动特性的影响，通过观察不同开槽翼型的流场图和分析不同开槽翼型槽内、槽出口的气流流速，优化出具有更好气动特性的开槽翼型。经过优化设计的开槽翼型在深失速环境下，失速迎角增大了8°，相较于初始翼型，有了较大的气动性能的提升，并证明了开槽在较大迎角时有改善翼型气动特性的特征。
Abstract:Airfoil stall is an aerodynamic phenomenon that needs to be considered in the design of wind turbines, and the main reason for stall is that the flow energy in the boundary layer is insufficient to provide sufficient adhesion. This problem can be effectively solved by injecting the high-momentum airflow under the airfoil into the upper separation zone when the airfoil is at a high angle of attack by using the internal slot of the airfoil. This research investigates the effects of two distinct slotted airfoil forms with varying widths on aerodynamic characteristics in an effort to improve the design of slotted airfoils. By observing the flow field diagram of different slotted airfoils and analyzing the flow velocity in and at the outlet of different slotted airfoils, the slotted airfoils with better aerodynamic characteristics can be optimized. In the deep stall environment, the Angle of attack of the optimized slotted airfoil increases by 8°. It has been demonstrated that the slotted airfoil can enhance the aerodynamic properties of the airfoil at larger angles of attack, as its aerodynamic performance has significantly increased when compared to the original airfoil.
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Key words:
- wind turbine airfoil /
- airfoil stall /
- inclined channel /
- boundary layer separation /
- flow velocity
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图 6 直开槽翼型与基准翼型升、阻力系数对比
Figure 6. Comparison of lift and drag coefficient between straight slotted airfoils and reference airfoils
图 7 直开槽翼型和基准翼型的升阻比
Figure 7. Lift-drag ratio of straight slotted and reference airfoils
图 8 基准翼型和直开槽翼型的流场分布
Figure 8. Flow field distribution for baseline and straight slotted airfoils
图 9 不同迎角下直开槽翼型气流流速变化
Figure 9. Changes in airflow velocity at different angles of attack of straight slot airfoil
图 10 2种不同槽道宽度的直槽道翼型模型
Figure 10. Two straight slot airfoil models with different slot widths
图 11 不同宽度直开槽翼型升、阻力系数和升阻比变化
Figure 11. Lift and drag coefficients and lift-drag ratio changes of straight slotted airfoil models with different widths
图 12 槽道尺寸为d=0.005c下不同α的流场
Figure 12. Flow field of airfoil with a d=0.05c straight slot at different angles of α
图 13 槽道尺寸为d=0.08c下不同α的流场
Figure 13. Flow field of airfoil with a d=0.08c straight slot at different angles of α
图 14 不同α下不同宽度直开槽翼型气流流速的变化
Figure 14. Flow velocity of airfoils with straight slots of different widths at different angles of attack
图 16 弧形开槽翼型和基准翼型升、阻力系数对比
Figure 16. Comparison of lift drag coefficient between curved slotted airfoil and reference airfoil
图 17 弧形开槽翼型和基准翼型升阻比对比
Figure 17. Contrast diagram of lift to drag ratio between curved slotted airfoil and reference airfoil
图 18 不同α下弧形开槽翼型流场分布
Figure 18. Flow field distribution of curved slotted airfoils at different angles of attack
图 19 不同迎角下直开槽翼型和弧形开槽翼型气流流速的变化
Figure 19. Under different angles of attack, the airflow velocities vary for airfoils with straight slots and airfoils with curved slots
图 20 2种不同槽道宽度的弧形槽道翼型模型
Figure 20. Two cambered slot airfoil models with different slot widths
图 21 不同宽度弧形开槽翼型升、阻力系数和升阻比变化
Figure 21. Lift and drag coefficients and lift-drag ratio changes of different models
图 22 不同α下2种弧形开槽翼型的流场分布
Figure 22. Flow field distribution of two curved slotted airfoils at different angles of attack
图 23 不同α下不同宽度弧形开槽翼型气流流速的变化
Figure 23. The variation of airflow velocity for curved slotted airfoils with different slot widths at various angles of attack
图 25 l型开槽翼型和基准翼型升、阻力系数对比
Figure 25. Lift and drag coefficient comparison between l-shaped optimized slotted and reference airfoils
图 26 l型开槽翼型和基准翼型升阻比曲线对比
Figure 26. Comparison of lift-drag ratio curves between l-shaped optimized slotted airfoil and reference airfoil
图 27 不同α下基准翼型和l型开槽翼型流场对比
Figure 27. Comparison of the flow fields of the two airfoil types with reference airfoil and l-slot airfoil under different attack angles
图 28 不同α下1型开槽翼型气流流速的变化
Figure 28. The variation of airflow velocity for l-shaped slotted airfoils at different angles of attack
表 1 网格收敛性研究使用的网格簇
Table 1. Cluster of mesh used in mesh convergence studies
网格类型 节点数量 网格数量 粗网格 10 404 10 200 中网格A 18 727 18 420 中网格B 19 927 19 620 细网格 24 827 24 420 
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