摘要
采用已通过风洞试验验证的CFD流场数值模拟方法,从流动机理出发分析空间涡量的变化,研究了翼吊发动机短舱涡流片的安装位置对着陆构型升力特性的影响。数值模拟的结果表明:由于发动机短舱以及挂架的影响,缝翼下偏后会在主翼上留下的台阶以及缝翼的端面等,大迎角时诱导出许多空间涡系,容易引发主翼上表面的分离。短舱涡流片诱导的空间涡能够有效地抑制这些空间涡系和低速区,提高失速迎角和最大升力系数,对于文中着陆构型,失速迎角提高2°,最大升力系数提高0.15。短舱涡流片后移或者下移均会引起空间涡的下移,有利于抑制大迎角下主翼中段低速气流。但下移涡流片的同时会降低空间涡的强度,使其抑制作用减弱。因此,为了提高失速迎角和最大升力系数,在设计过程中需综合考虑短舱涡流片所诱导空间涡的强度和位置。针对某型民用运输机着陆构型中短舱涡流片因几何约束需对其位置进行重新设计的问题,根据上述研究结论,综合权衡空间涡的强度及位置,重新设计了短舱涡流片的位置。计算结果表明,重新设计涡流片的位置后,几何约束得到了满足,着陆构型的最大升力系数仅损失0.015,仍然能够满足设计指标。
This paper applies the methods of CFD simulation of fluid flow,which are validated by wind tunnel results,to analyze the influences of installation location of nacelle chine on the lift performance of landing configuration from the change of spatial vortices.The numerical simulation results show that because of the influences of nacelle and pylon,the end of slats and cuts of main wing left by the deflection of slats, will induce a series of vortices in high angle of attack（α）,which could bring separation in the upper surface of main wing easily.The vortex induced by nacelle chine can depress these vortices and low speed region of flow field above the main wing behind nacelle so that the stallingαand maximum lift coefficient will be improved.Regarding the landing configuration in this paper,its stallingαand maximum lift coefficient are increased by 2°and 0.15respectively by the installation of nacelle chine.The vortex induced by nacelle chine will move downwards once the chine is put back or down,which leads to stronger restraint effects to other vortices and lower speed region.In order to increase the stallingαand maximum lift coefficient of landing configuration,both of the location and strength of vortex induced by nacelle chine must be taken into consideration in the design process.Because of some geometry restraints and adopting above investigation results, the location of nacelle chine is redesigned through the tradeoff study for the location and strength of space vortex.The CFD result shows that for the redesigned location of chine,geometry restraint is satisfied and the loss of maximum lift coefficient of landing configuration is less than 0.015,which still meets the design requests.
出处
《空气动力学学报》
CSCD
北大核心
2014年第2期190-196,共7页
Acta Aerodynamica Sinica
关键词
增升装置
气动性能
翼吊发动机
短舱涡流片
high-lift system
aerodynamic performance
nacelle beneath the wing
nacelle chine
