飞机着陆过程中提高气动性能的一种新方法

为了提高飞机在着陆过程中的气动性能,提出了一种新方法:将翼型上翼面的一段表面设计为活动部分。当飞机进入着陆阶段的较大迎角时,通过活动部分在上翼面形成一个台阶产生稳定的驻涡,再联合Gurney襟翼,达到同时提高翼型的升力、失速迎角及增加翼型阻力的目的。在NACA2415翼型上对上述方法进行了验证。结果表明,翼型最大升力系数从原始翼型的1.548 232提高到2.160 687,最大升力系数所对应的迎角可以从原始翼型的17°提高到20°。可见,所提出的新方法对提高飞机的着陆性能是有效的。

New method of improving the aircraft aerodynamic performance in the process of aircraft landing

In order to improving the aircraft aerodynamic performance in the process of aircraft landing,a new method is presented: to design a part of the upper surface of the airfoil profile to change into a movable part.When the airplane accesses to the relatively larger angle of attack during the period of landing,a step can be formed on the upper surface by the movable part,thus a stable trapped vortex is generated.By joint operation of a Gurney flap,both effects of improving the lift and the stall angle of attack will be achieved,while drag of airfoil profile will also be increased.By carrying the above method into NACA2415 airfoil,the numerical results show that the maximum lift coefficient can be increased from 1.5482320 of the original airfoil to 2.1606871,and the stall angle of attack of the airfoil can be increased from original 17 degrees to 20 degrees.Therefore,the new method presented here is believable to improve aircraft landing performance.