无尾布局后体超声速航向增稳设计方法

针对无尾布局超声速航向静稳定性不足的问题，提出一种基于超声速压缩/膨胀流动的后体超声速航向气动增稳设计方法。首先通过无尾布局扁平后体和常规后体方案航向静稳定性和表面流场差异的对比，明确了后体超声速航向增稳设计思路。然后基于后体参数化外形分析了后体型面对于布局超声速航向静稳定性的影响规律。最后通过评估典型后体方案的综合气动特性验证了后体超声速航向增稳设计方法的可行性。研究表明：重心后侧向投影面积增量、后体脊线以及后体截面曲线是影响后体型面超声速航向增稳能力的3个主要参数。与常规后体型面相比，通过超声速航向增稳设计获得的后体型面能够在布局阻力变化不大的情况下，显著改善无尾布局在跨声速和超声速状态的航向静不稳定性。

After body supersonic directional stability augmentation method for tailless configuration

Aiming at the problem of insufficient supersonic directional static stability in the tailless configuration aircraft design, an aerodynamic supersonic directional augmentation method for the after-body design is presented. Firstly, the design idea of after-body supersonic directional augmentation was made clear by the comparative analysis of the directional static stability and surface flow field between flat after-body and conventional after-body of tailless configuration. And then the influence law of the after-body shape on the supersonic directional static stability was analyzed based on the parametric configuration. Finally, the effectiveness of the after body supersonic directional stability augmentation method was verified by the comprehensive aerodynamic characteristics numerical evaluation of the typical after-body scheme. The results show that the increment of after-body lateral projected area, after-body surface spine curves and after-body surface section curves are the three most important parameters which affect the ability of after body supersonic directional augmentation. Compared to the conventional after-body, the after-body shape designed by the supersonic directional augmentation method can dramatically decrease the directional static instability of the tailless configuration at transonic and supersonic flight with drag basically unchanged.