摘要
通过试验方法分析了三角翼前缘分离涡与垂尾抖振之间的关系,深入研究了尾迹流动对垂尾抖振各阶模态的激励作用。计算得到了垂尾模型固有频率及各阶模态。在风洞试验中,应用激光片光烟流场显示技术,得到了三角翼模型在风速为30m/s下,各迎角的涡结构;使用加速度传感器测量了垂尾翼根和翼梢的抖振响应;使用热线风速仪测量了垂尾翼根和翼梢位置的脉动速度分量。结果表明:前缘涡破裂后产生的高湍流度的尾迹是垂尾抖振的直接原因,抖振边界与涡破裂的强度和位置有关;涡破裂后尾迹与垂尾产生共振,使得抖振加速度响应频率与垂尾固有频率一致;涡破裂后,在较小迎角下,尾迹对垂尾的高频振动模态的激励较为明显,在较大迎角下,涡破裂流动对垂尾低频振动模态的激励加强了。
The relationship between breakdown vortex and vertical tail buffeting is analyzed by experiment. The stimulation effects which the wake of breakdown vortex exerts on various modes of vertical tail buffeting are investigated in detail. The normal modes and natural frequencies of vertical tail model are calculated by numerical method firstly. Then, the vortex structure of delta wing at different angles of attack is recorded by laser sheet flow visualization technique at 30 m/s. The buf- feting responses of vertical tail tip and root are measured by accelerometer. The oscillation velocity of the wake is measured using the hot-wire anemometer, The results show that the vertical tail buffeting originates from the breakdown vortex. The buffet boundary is related to the location and intensity of the vortex breakdown. The wake of the vortex resonates with the vertical tail and further reinforces the buffeting phenomenon. As a result, the buffeting frequencies are identical with natural frequencies of the tail structure. The broken-down vortex at relative low angles of attack generates high frequency vibration mode of the vertical tail whereas at high angles of attack gives rise to the low frequency vibration mode.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2016年第2期491-503,共13页
Acta Aeronautica et Astronautica Sinica
基金
重点实验室预研基金(9140C420301110C42)~~
关键词
垂尾抖振
大迎角
前缘涡
抖振加速度
振动模态
vertical tail buffeting
high angles of attack
leading edge vortex
buffeting acceleration
vibration mode
