摘要
来流湍流度是影响翼尖涡不稳定运动及其发展演化行为的重要因素。本文在基于机翼弦长的雷诺数Re_(c)=1.1×10^(4)条件下,通过时间解析的体视粒子图像测速技术测量了不同来流湍流度条件下孤立翼尖涡在不同流向站位处的速度场。结果表明,来流湍流度的增大显著增强了翼尖涡的不稳定摇摆运动,不同来流条件下翼尖涡摇摆运动幅值沿流向线性增长,并满足对来流脉动速度的统一标度规律。摇摆运动对翼尖涡统计量的计算有显著影响,通过系综平均方法修正摇摆运动对统计量测量结果的影响后进一步发现,在本实验测量的参数空间内不同来流条件下翼尖涡涡核半径满足相同的增长规律,翼尖涡沿流向的发展演化表现为黏性扩散为主导的衰减机制。
Freestream turbulence significantly affects the unstable wandering motion and the evolution of the wingtip vortex.In the present study,time resolved-stereo particle image velocimetry(TR-SPIV)measurements were carried out under different freestream conditions at a chord-length-based Reynolds number of Re_(c)=1.1×10^(4).The results show that grid turbulence significantly enhances the wandering motion of the wingtip vortex.The wandering amplitude increases linearly along the streamwise direction and scales well with freestream velocity fluctuations.The‘smearing out’effect of vortex wandering on the statistic characteristics is dramatic and can be corrected by the ensemble average method.Moreover,it is found that the core radius follows the same growth law under different flow configurations involved in the measured parameter space,indicating that the evolution of the wingtip vortex along the streamwise direction is dominated by viscous diffusion.
作者
王志远
潘翀
程泽鹏
WANG Zhiyuan;PAN Chong;CHENG Zepeng(School of Aeronautic Science and Engineering,Beihang University,Beijing 100191,China;Tianmushan Laboratory,Hangzhou 310023,China)
出处
《空气动力学学报》
北大核心
2025年第1期121-129,61,I0002,共11页
Acta Aerodynamica Sinica
基金
国家自然科学基金(12202031,12225202,91952302)
天目山实验室基金(TK2023-B-004)。
关键词
翼尖涡
湍流度
摇摆运动
统计特性
体视粒子图像测速
wingtip vortex
turbulence intensity
vortex wandering
statistic characteristics
SPIV
