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本文研究了伞翼几何参数变化对纵向与横侧气动特性的影响。在实验中改变的因素包括伞翼后缘形状,翼面上的肋条,伞翼顶角,边条小翼,外翼弦长,龙骨形状,伞翼的张开比和上反角。 研究结果表明,对于单龙骨双叶伞翼,后缘形状改变对气动特性有很大影响,采用向内弯曲的后缘与直后缘的情况相比,能使伞翼的最大升阻比提高很多。在翼面上加肋条,使伞翼的阻力减小、升阻比增大。对于顶角比较大的翼面,增加顶角将获得更大的升阻比。在这种翼面上加边条小翼,可使最大升力系数提高并且改善失速特性。采用适当弯曲的龙骨也使升力特性得到改进。 增加伞翼的张开比使航向静稳定度增大。增加伞翼的上反角使横向静稳定度增大,航向静稳定度减小。在一定范围内,改变上反角对横向和航向稳定性的影响与张开比的作用相反。
In this paper, the influence of the geometric parameters of wing on the aerodynamic characteristics of the longitudinal and lateral sides is studied. Factors that have changed in the experiment include the shape of the trailing edge of the wing, the ribs on the airfoil, the apex of the wing, the winglet of the wing, the outer chord length, the shape of the keel, the ratio of opening of the wing and the upper dihedral. The results show that for the single-keel bilobes, the trailing edge shape has a great influence on the aerodynamic characteristics. Compared with the case of the straight trailing edge, the maximum drag / drag ratio of the wing can be increased a lot of. Ribs in the wing surface, so that the resistance of the wing to reduce the lift-drag ratio increases. For larger apex angles, increasing the apex angle will result in a larger lift-drag ratio. Adding edge winglets to such airfoils increases the maximum lift coefficient and improves stall characteristics. The use of properly curved keel also improves lift characteristics. Increasing the opening of the wing increases the stability of the heading. Increase the upper wing of the antithetic so that the lateral static stability increases, the heading of static stability decreases. Within a certain range, the effect of changing the upper dihedral angle on the stability of the transverse and heading directions is opposite to that of the opening ratio.