摘要
钝头体大迎角飞行时会出现随机的非对称流动现象,引起不确定的较大侧向力,进而使其偏离运行轨道。通过在钝头体头部施加人工扰动块可以固定其大迎角下的非对称流场结构,得到确定的侧向力,以利于改善钝头体的大迎角飞行特性及机动性。本文讨论了在头部人工扰动块主控流场结构的基础上,模型后体对侧向力影响的存在性问题,在迎角为50°、雷诺数为1.54×105的条件下,利用实验对周向角为90°和270°、子午角为10°的扰动位置的球形扰动主控下的侧向力影响因素进行了研究。发现钝头体大迎角下的非对称流动结构在头部主控的基础上,后体对非对称流动的影响不会消失,且其为影响头部扰动主控作用的重要因素。尽管模型后体的影响不会改变钝头体头部对于流场结构的主控地位,但会影响头部扰动控制的精准程度。所以在通过钝头体头部施加扰动进而得到确定的侧向力的同时,还需要减小模型后体对流场的影响,对其结构和加工质量进行优化,以更好地通过人工扰动主控流场结构。
The random asymmetric flow over its blunt-nose body is generated when it flies at high angles of attack,thus resulting in unexpected side-forces,which leads to the trajectory deviation.The pattern of asymmetric flow and its corresponding side-force are determined by attaching an artificial perturbation on the nose of the blunt-nose body at high angle of attack,which is helpful to improve the flight characteristics and maneuverability of blunt-nose body.Based on the major control effect of the artificial perturbation on the asymmetric flow,the effect of the afterbody of the model is discussed in this paper.Experimental tests are conducted to investigate influence factor of side force at high angle of attack 50°and ReD=1.54×10^5,with the perturbation locations of circumferential angles 90°/270°and meridian angle 10°.It is found that the effect of afterbody is still existent as an important effect factor,which effects the major control of the nose of the model to the asymmetric flow.Though the status of the main control from perturbation cannot be changed by the afterbody,the accuracy of control of perturbation on the nose is decreased.Therefore,the processing quality of afterbody should be enhanced to intensify the major effect of artificial perturbation on the asymmetric flow over the blunt-nose body.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2017年第9期217-224,共8页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金(11472028)
中国航天科技集团公司航天科技创新基金(CASC01)
2015装备预研基金~~
关键词
钝头体
非对称流动
主控
大迎角
人工扰动
blunt body
asymmetric flow
main control
high angle of attack
artificial perturbation
