摘要
导弹全方向攻击时会产生由旋涡主导的复杂流动,发生转捩和流动分离,对导弹的机动性和控制能力具有重大影响。为探索攻角及马赫数对弹体流动形态的影响,针对某细长旋成体在FD-12风洞开展高速粒子图像测速及荧光油流试验,来流Ma分别为0.4、0.6、0.8,攻角范围α为0°~180°,获取了细长体背风区的流场特性演化规律。研究结果表明:当攻角α<90°时,随着攻角的增大,模型背风区流场从附着流变化为分离流,且分离涡从对称变为非对称,最终演化为非定常流动;当攻角α>90°时,情况有所不同,α=100°及α=120°时背风区存在非定常涡脱落现象,时均流场具有明显的非对称性;当攻角α=150°时,迎风面分离区出现不对称偏移,初始分离区下边界已越过模型端面,在模型中后部形成分离线;当攻角α=180°时,时均流场没有明显的特征,在模型头部位置出现了环形分离区及再附区,表明由于底部扰动的影响,该截面流场呈现局部的非定常、非线性流动状态;在攻角相同情况下,增大流场的来流Ma,不但会使分离涡的影响范围变大,也会导致分离涡的位置抬高。
The transition and flow separation dominated by vorticity will occur,which have a significant impact on the maneuverability and control ability of missile,when a missile launches an all-aspect attack.The particle image velocimetry(PIV)and fluorescent oil flow visualization experiments are carried out in the FD-12 wind tunnel for a slender body in order to explore the influences of angle of attack and Mach number on the flow pattern in the leeward region of slender body.The characteristics of the flow field in the leeward region of slender body were obtained at the angles of attackαfrom 0°from180°with Ma=0.4/0.6/0.8.The results show that the flow in the leeward region of the model changes from attached flow to separation flow,and the separation vortex vary from symmetry to asymmetry when the angle of attack is<90°.The unsteady vortex shedding phenomenon exists in the leeward region and the time-averaged flow field has an obvious asymmetry characteristic at 100°and 120°angles of attack.The separation zone of windward face begins to appear asymmetric offset forα=150°.The lower boundary of initial separation zone crosses the end face of the model,forming a separation line in the rear of the model.When the angle of attack changes to 180°,there is an obvious ring-shaped separation zone and re-attachment zone at the upwind face and no obvious separation zone at the rear of the model.The results indicate that the flow field presents complex unsteady and nonlinear flow states due to the influence of bottom.In addition,the increase of the Mach not only enlarge the influence range of separation vortex,but also promote the position of separation vortex at the same angle of attack.
作者
李晓辉
王宏伟
熊红亮
石伟龙
任少洁
黄湛
LI Xiaohui;WANG Hongwei;XIONG Hongliang;SHI Weilong;REN Shaojie;HUANG Zhan(China Academy of Aerospace Aerodynamics,Beijing 100074,China)
出处
《兵工学报》
EI
CAS
CSCD
北大核心
2024年第3期818-827,共10页
Acta Armamentarii
关键词
细长体
大攻角
粒子图像测速
流动分离
旋涡
slender body
high angle of attack
particle image velocimetry
flow separation
vortex
