襟翼相对长度对翼型流场结构影响

以NACA0018为基准翼型,采用Fluent数值模拟的方法,对比研究了襟翼相对长度和翼缝相对宽度对翼型流场结构及升、阻力特性的影响;文章分别选取了襟翼相对长度分别为0.2、0.3和0.4和翼缝相对为1.0%,分析襟翼相对长度对翼型气动性能的影响。数值结果表明:由于襟翼对翼型周围主涡发展和变化的影响,不仅改善了翼型的失速特性,同时也提高了翼型的气动性能。襟翼翼型的失速攻角在此次研究范围内均大于基准翼型,在攻角小于失速攻角时,襟翼翼型的升力系数均小于基准翼型,阻力系数均高于基准翼型,但升力系数的最大值均高于基准翼型;随着襟翼相对长度增大,翼型临界攻角逐渐减小;在攻角接近翼型失速攻角时,升力系数先增大后减小;襟翼长度相同时,随着翼缝相对宽度的增大,升力系数逐渐减小。

Relative Length of Flap Effect on Airfoil Flow Field Structure

Based on symmetrical airfoil NACA0018 airfoil,using Fluent software numerical simulation method comparative study the relative length and the wing flap seam relative width of airfoil flow field structure and the influence of the resistance properties;The article selected the flap relative length are 0. 2,0. 3 and 0. 4 and slot relative width of 1. 0%,emphatically analyzed the flaps relative length effect on airfoil aerodynamic performance The numerical results show that:due to the impact of the main vortex development and change around the airfoil by flap,not only to improve the airfoil stall characteristics,but also improve the aerodynamic performance of airfoil. Flap airfoil stall Angle of attack within the scope of the study were greater than the benchmark airfoils,when the angle of attack is less than the stall angle of attack,the wing flap type of lift coefficient are less than the benchmark airfoils,drag coefficient were higher than benchmark airfoils,but the maximum lift coefficient are higher than the benchmark airfoil;as the relative length increases,flap airfoil critical angle of attack decreases,lift coefficient is close to the airfoil stall angle of attack,its value to present first increases then decreases;flap length at the same time,with the increase of relative width of the slot,the lift coefficient decreases.