相对厚度对低雷诺数流动中翼型动态气动力特性的影响

以固定翼微型飞行器为研究背景,研究了相对厚度对低雷诺数流动中翼型动态气动力特性的影响规律.采用Roe迎风差分格式和双时间步迭代方法,数值求解拟压缩性修正不可压Navier-Stokes方程,给出了数值算法与实验数据的对比验证.以翼型弦长为特征长度,在Re=500～50,000情况下,选取不同最大相对厚度和不同最大相对厚度位置的翼型,计算了其等速上仰时的动态气动力,结果表明前者对气动力影响显著,较小最大相对厚度值可获得较大的动态升阻比.

The effect of relative thickness to the dynamic aerodynamic characteristics about pitching airfoils

Numerical computations for Micro Aerial Vehicle(MAV) applications were conducted to analyze the effects of airfoil relative thickness and its position to dynamic aerodynamic characteristics of airfoil with identical pitching rate at low Reynolds number.The dual-step Roe schema developed by Rogers was used to solve the incompressible Navier-Stokes equations revised by artificial compressibility method.Verification was done between the numerical results and Walker's experimental results.Taken the length of airfoil chord as the characteristic length,at the low Reynolds number(Re=500,5000 and 50000),the dynamic aerodynamic characteristics were researched about different values of maximum relative thickness and position.The research results indicated that the effect of the former is more obvious than the latter,and the greater maximum relative thickness leads to the larger dynamic lift-drag ratio.