亚临界雷诺数圆柱涡致振动的实验研究  

Experiments on vortex-induced vibration of a cylinder at subcritical Reynolds numbers

作　　者：吕振 张伟伟[1] 寇家庆 LYU Zhen;ZHANG Weiwei;KOU Jiaqing(School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]西北工业大学航空学院,西安710072

出　　处：《空气动力学学报》2023年第1期101-107,共7页Acta Aerodynamica Sinica

摘　　要：近年来,数值模拟结果表明圆柱涡致振动现象可在低至20的亚临界雷诺数下发生,但目前尚无相关实验证明该种现象的存在。本文首先研发了适用于低雷诺数流固耦合实验的旋转水槽,而后在此基础上开展了亚临界雷诺数下圆柱涡致振动实验,分别研究了支撑频率和雷诺数对涡致振动响应的影响。发现圆柱涡致振动存在的最低雷诺数为23,与数值模拟结果接近,证实了亚临界雷诺数涡致振动的存在;另外,发生亚临界涡致振动时,在尾迹区观测到了频率与圆柱振动频率一致的卡门涡脱,说明弹性支撑特性会使得流动稳定性降低,证实了相关数值模拟结果的正确性。Numerical simulations in recent years have shown that vortex-induced vibrations(VIV) of cylinders can occur at subcritical Reynolds numbers as low as 20, but relevant experimental evidence for the existence of such phenomenon has not been observed. In this paper, we first built a rotating channel for lowReynolds-number experiments. Then, VIV at subcritical Reynolds numbers were studied in this rotating channel.The effects of support stiffness and Reynolds number on the VIV were investigated. The lowest Reynolds number for the occurence of VIV of a cylinder is 23, which is close to the numerical simulation results. It confirms that the subcritical VIV indeed exists. In addition, von Kármán vortex shedding was found during VIV and the vortex shedding frequency is the same as that of the cylinder. It indicates that the elastic support makes the flow less stable, which also agrees well with previous numerical results.

关 键 词：涡致振动 亚临界雷诺数 旋涡脱落 锁频 流固耦合 圆柱绕流 

分 类 号：V211.7[航空宇航科学与技术—航空宇航推进理论与工程]