摘要
此次研究对水平板附近低质量比(m*=43.6)圆柱的涡激振动(vortex-induced vibration,VIV)问题开展了风洞试验,其中圆柱与平板的间隙范围为0≤S/D≤2.5。结果表明:当S/D=0时,随着约化速度U*的增加,圆柱始终保持静止;当0<S/D<0.6时,圆柱碰壁振动,其向上振幅略高于向下振幅,且尾流形式单一;当S/D≥0.6时,圆柱振动不再碰壁;从S/D=0.8开始,响应振幅明显出现三个分支,同时尾流形式变得更加丰富;当S/D达到2.5时,平板与圆柱之间的相互影响可近似忽略。平板表面的气压分布受到圆柱振幅以及间隙比的综合影响。当圆柱发生较大振动时,下方平板表面的脉动风压系数显著增加,且风压的脉动频率始终与圆柱的响应频率保持一致。
The vortex-induced vibration(VIV)of a low mass circular cylinder near a flat plate was experimentally studied in a wind tunnel.S/D,the gap-to-diameter ratio,was 0≤S/D≤2.5,and m^(*),the mass ratio of cylinder,was 43.6.Results show that,when S/D=0,the cylinder remains stationary all the time,with increasing U^(*),and the vortex shedding is completely suppressed. When 0 < S/D < 0.6,the cylinder hits the wall periodically, and the upwardamplitude is slightly larger than the downward one, and its wake form is single. When S/D≥0.6, the cylinder vibrationwill not touch the wall. Different branches of the response amplitude appear for S/D≥0.8, and the wake form of thecylinder becomes more abundant. When S/D reaches 2.5, the influence of the plate on the cylinder can be approximatelyignored. The pressure distribution on the plate surface is affcted by the cylinder amplitude and the gap. When thecylinder vibrates greatly ,the fluctuating pressure on the surface of the plate increases significantly, and the fluctuatingfrequency is always consistent with the vibration frequency of the cylinder.
作者
陈聪
王汉封
邓国浩
姚小敏
CHEN Cong;WANG Hanfeng;DENG Guohao;YAO Xiaomin(School of Civil Engineering,Central South University,Changsha 410075,China;Nation Engineering Laboratory for High-Speed Railway Construction,Central South University,Changsha 410075,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2022年第16期65-72,共8页
Journal of Vibration and Shock
基金
国家自然科学基金(52078505)。
