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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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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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