Experimental investigation on two rectangular wings with NACA0012 and NACA4415 profiles is performed at different Reynolds numbers to understand their aerodynamic behaviours at a high α regime. In-house developed numerical code VLM3D is validated using this experimental result in predicting the aerodynamic characteristics of a rectangular wing with cambered and symmetrical wing profile. The sectional coefficient of lift ( C l sec ) obtained from the numerical approach is used to study the variation in spanwise lift distribution. The lift and moment characteristics obtained from wind tunnel experiments are plotted, and change in the maximum coefficient of lift ( C L max ) and stall angle (α stall ) are studied for both of the wing sections. A significant addition to the novelty of the present experiments is to provide some comparison of the numerical induced drag coefficient, C D i with experimentally fitted model coefficients using least square technique. A novel method is used to examine the aerodynamic hysteresis at high angles of attack. The area included in the lift- Re curve loop is a measure of aerodynamic efficiency, and its variation with angle of attack and wing plan forms is studied.

中文翻译：

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流过矩形翼的数值分形方法的实验验证

在不同雷诺数下对具有 NACA0012 和 NACA4415 轮廓的两个矩形机翼进行实验研究，以了解它们在高 α 状态下的空气动力学行为。使用该实验结果对内部开发的数值代码 VLM3D 进行了验证，以预测具有弧形和对称机翼轮廓的矩形机翼的空气动力学特性。从数值方法获得的升力截面系数（C l sec ）用于研究展向升力分布的变化。绘制了从风洞实验中获得的升力和力矩特性，并研究了两个机翼截面的最大升力系数 (CL max ) 和失速角 (αstall ) 的变化。本实验新颖性的一个重要补充是提供数值诱导阻力系数 CD i 与使用最小二乘法的实验拟合模型系数的一些比较。一种新方法用于检查大迎角下的空气动力滞后。包含在升力-Re 曲线环中的面积是衡量空气动力效率的指标，研究了其随迎角和机翼平面形状的变化。