论文部分内容阅读
本文提出一个方法,用来确定不可压流中大攻角细长体在有效横流雷诺数10~4～10~8的范围内,由旋涡引起的最大侧向力和伴随的偏航力矩。利用垂直于气流圆柱上的三维非定常气流分离相似,得到旋转细长体由定常旋涡引起的最大侧向力的边界。可以看出,在临界有效雷诺数的范围内,当弹体的一侧发生亚临界分离,而另一侧发生超临界分离时,旋涡引起的侧向力最大。尽管,该方法只适用于仅存在单个不对称旋涡的弹体,但可以把它推广,提供一个基本的积木法,来确定受不对称多涡对影响的,长弹体的方向稳定性边界。
In this paper, a method is proposed to determine the maximum lateral force and the associated yawing moment caused by vortices in the range of effective cross flow Reynolds number of 10 ~ 4 ~ 10 ~ 8. By using the three-dimensional unsteady flow separation perpendicular to the cylinder of the gas flow, the boundary of the maximum lateral force caused by the steady vortex is obtained. It can be seen that in the range of the critical effective Reynolds number, the lateral force caused by the vortex is the maximum when the subcritical separation occurs on one side of the projectile and the supercritical separation occurs on the other side. Although this method is only applicable to the projectile with only a single asymmetric vortex, it can be generalized to provide a basic building block method to determine the directional stability boundary of a projectile affected by asymmetric vortices.