【摘要】 翼型的失速特性是失速调节型水平轴风力机的气动性能分析和颤振分析的基础。许多涉及这类问题的研究大多只给出了翼型刚开始失速时的计算结果。然而在正常运行工况下叶片端部翼型的深失速特性是风力机的最关键的一类问题。通过求解二维非定常、可压的Ｎ－Ｓ方程计算了风力机常用翼型ＮＡＣＡ４４１８的绕流特性。Ｎ－Ｓ方程在贴体坐标系中给出，用Ｐｏｉｓｓｏｎ方程法生成了Ｃ型网格。数值计算中采用了一种改进的ＬＵ－ＳＧＳ格式。将翼型的升阻特性的计算值与实验值进行了比较，两者吻合较好。更多还原

【Abstract】 The characteristics of an airfoil at stall conditions are the analysis base both for the performance of stall regulated HAWT rotors and for the flatter estimation of the blades.Many calculations involved in this question gave the results only when airfoils begin to stall.However,the deep stall of an airfoil of blade tip is an critical one for the HAWT rotors especially the stall regulated HAWTs within the normal operation conditions.This paper presents a numerical study of flow around an airfoil(NACA4418)at large angles of attack.The two dimensional N S equations in a body fitted system is adopted, and the C type grid system is generated by Poisson equations method.Numerical solutions are obtained by using an improved LU SGS format.The numerical results of lift and drag coefficients are compared with the wind tunnel test data.The comparison shows good agreement between the computational and experimental data.更多还原