均匀流场中阶梯圆柱涡激振动试验研究  

Experimental study on the vortex-induced vibration of a stepped cylinder in uniform flow

作　　者：殷彤 及春宁[1] 宋立群 袁德奎[2] YIN Tong;JI Chunning;SONG Liqun;YUAN Dekui(State Key Lab of Hydraulic Engineering Simulation and Safety,Tianjin University,Tianjin 300350,China;School of Mechanical Engineering,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学水利工程仿真与安全国家重点实验室,天津300350 [2]天津大学机械工程学院,天津300350

出　　处：《振动与冲击》2022年第18期258-265,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金(51779172)资助项目。

摘　　要：对均匀流场中雷诺数Re=450~6 000内的阶梯圆柱涡激振动(VIV)进行了试验研究,并考虑了大直径段覆盖率R和直径比D/d的影响。结果表明:当R=25%~75%时,阶梯圆柱振动响应出现“过渡分支”。在过渡分支上,圆柱振幅逐渐增大,升力先增后减。随着覆盖率R和直径比D/d增加,过渡分支逐渐变宽,初始分支持续收窄。研究还发现了阶梯圆柱涡激振动中的“双锁定”现象:在锁定区间内,阶梯圆柱振动频率随折合流速的增加先后锁定在两个频率上,且第一锁定频率略低于第二锁定频率。两次锁定与响应分支间存在明显的对应关系。An experimental study on the vortex-induced vibration(VIV) of a stepped cylinder in uniform flow was performed,with the Reynolds number Re=450~ 6 000.The effects of the coverage ratio R and diameter ratio D/d on the vibration responses were investigated.The results show that a “transition branch” appears in the vibration responses of the stepped cylinder when R=25%~75%.On the transition branch,the amplitude increases gradually,and the lift force first increases and then decreases.With the increase of R and D/d,the reduced velocity range for the transition branch extends,while that for the initial branch shrinks.In the lock-in region,the oscillation frequency of the cylinder sequentially locks onto two frequencies with the increase of the reduced velocity,which is termed as the “dual lock-in”.There is an obvious correspondence between the lock-in regions and the response branches.

关 键 词：阶梯圆柱 涡激振动(VIV) 覆盖率 直径比 双锁定 

分 类 号：P751[交通运输工程—港口、海岸及近海工程] TB531[天文地球—海洋科学]