蜻蜓翼三维流动结构的演变  

Revolution of flow structures around model wing of dragonflies in hovering flight

作　　者：赖国俊[1] 申功炘[1] 

机构地区：[1]北京航空航天大学航空科学与工程学院,北京100191

出　　处：《北京航空航天大学学报》2013年第6期711-716,共6页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家自然科学基金资助项目(10772017);985基金二期资助项目

摘　　要：为了与蜻蜓前后翼流动干扰的流动结构作比较,首先研究了悬停飞行状态下单个蜻蜓翼周围的三维流动结构,利用一套机电拍动翼运动模拟机构模拟了一个蜻蜓翼的拍动,使用数字体视粒子图像测速技术(DSPIV,Digital Stereo Particle Image Velocimetry)和多切面锁相技术分别测量了两个下拍拍动相位时刻(t=0.25T,0.375T)和两个上拍拍动相位时刻(t=0.75T,0.875T)蜻蜓翼周围的瞬时空间三维流场,运用局部涡识别准则中的λci准则来识别和显示了流场中的三维涡结构,还展示了蜻蜓翼各个展向测量截面中的|ωz|等值线、蜻蜓翼前缘涡的涡核线相对于蜻蜓翼上翼面的空间位置以及前缘涡在各个展向测量截面中的截面环量等.实验结果揭示了蜻蜓翼周围的三维流动结构在蜻蜓翼拍动时的演变历程.To study the three dimensional flow structures around a single flapping wing of dragonflies in hovering flight for future experimental comparison with flow structures around a fore-or hind wing of dragonflies,an electromechanical flapping mechanism mounted with a model wing was used to simulate the flapping motion of a dragon wing in this experiment.Three dimensional instant flow fields around the flapping wing were measured respectively at two downstroke phases（t=0.25T,0.375T） and two upstroke phased（t=0.75T,0.875T） with the digital stereo particle image velocimetry（DSPIV） and the multi-slice phase-locked technique.Three dimensional vortex structures were visualized with the local vortex identification scheme.It also was presented that the contour lines of z component of vorticity in each spanwise measuring plane,the vortex core position of the leading edge vortex（LEV） with respect to the upper wing surface and LEV sectional circulation at each spanwise measuring position.The results show that the revolution of the three-dimensional flow structures around the dragonfly wing during its stroking.

关 键 词：流动测量 数字体视粒子图像测速技术 蜻蜓 悬停飞行 流动结构 流动分离 前缘涡 

分 类 号：O351[理学—流体力学]