Abstract The lift coefficient for a flat plate at low angles of attack is obtained experimentally for various aspect ratios (AR ​= ​1, 2, 4, 8) and moderate Reynolds numbers (Re ​= ​40 ​× ​103 to Re ​= ​200 ​× ​103). The variation of the lift coefficient with the angle of attack in the pre-stall region is consistent with a linear slope approximation. We consider that this slope is a function of both the aspect ratio and Reynolds number. In this research, we provide a correlation that can predict the lift slope value with an average error of less than 5%. This correlation captures the idea of Prandtl’s finite wing theory and extends its application for any Reynolds number. The same correlation is tested against other literature experiments providing very accurate results even outside our range of measured AR and Re.

中文翻译：

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中等雷诺数下矩形平板翼的升力曲线斜率

摘要 平板在低攻角下的升力系数是通过实验获得的，对于各种纵横比（AR = 1, 2, 4, 8）和中等雷诺数（Re = 40 × 103 to Re = 200 × 103)。在预失速区域升力系数随迎角的变化与线性斜率近似一致。我们认为该斜率是纵横比和雷诺数的函数。在本研究中，我们提供了一种相关性，可以预测平均误差小于 5% 的提升斜率值。这种相关性抓住了普朗特有限翼理论的思想，并将其应用扩展到任何雷诺数。即使在我们测量的 AR 和 Re 范围之外，也可以针对其他文献实验测试相同的相关性，提供非常准确的结果。