正方形布置四圆柱结构流致振动响应特性研究
STUDY ON THE FLOW-INDUCED VIBRATIONS OF FOUR SQUARE-ARRANGED CIRCULAR CYLINDERS
胡中明 1王嘉松 2孙远坤 2郑瀚旭 2范迪夏3
作者信息
- 1. 黄淮学院建筑工程学院,河南驻马店 463000;上海交通大学船舶海洋与建筑工程学院,上海 201100
- 2. 上海交通大学船舶海洋与建筑工程学院,上海 201100
- 3. 西湖大学工学院,杭州 310030
- 折叠
摘要
通过风洞实验研究了正方形布置四圆柱的流致振动特性,实验雷诺数Re = 3200～28900,圆柱间距比S/D = 1.5～4.0(S为两圆柱圆心间距,D为圆柱直径),质量比m*≈ 345.0.结果表明,当S/D≤2.0 时,上游圆柱1 和 2 呈现涡激振动和类弛振耦合响应,下游圆柱 3 和 4 呈现涡激共振和尾流弛振耦合响应;当S/D=2.5～3.0,上游圆柱 1 和 2 除了在约化速度超过一定值时存在弱振动外,基本接近单圆柱涡激振动响应,下游圆柱 3 和4 表现为分离的涡激共振和尾流弛振响应;当S/D = 4.0 时,上游圆柱 1 和 2 振动响应几乎和单圆柱一样,而圆柱 3 和 4 仍呈现分离的涡激共振和尾流弛振响应.当圆柱呈现涡激振动(上游圆柱)或涡激共振(下游圆柱)时,涡脱频率fs锁定于固有频率fn的 1 倍谐频,而当圆柱呈现剧烈的类弛振响应(上游圆柱)或尾流弛振响应(下游圆柱)时,fs则会出现明显的多倍谐频;圆柱模型振动频率fo主频始终锁定于fn的 1 倍谐频.通过对比正方形四圆柱和双圆柱流致振动特性,发现双圆柱动力学响应规律在一定程度上仍适用于正方形布置四圆柱.
Abstract
Flow-induced vibrations(FIVs)of four square-arranged circular cylinders have been investigated in a wind tunnel at Re = 3200～28900.The spacing ratios S/D are from 1.5 to 4.0(S is the center-to-center spacing between two cylinders and D is the cylinder diameter)and the mass ratio m*≈ 345.0.Results show that,when S/D≤2.0,cylinder 1 and cylinder 2(upstream cylinder)present an combined vortex-induced vibration(VIV)and galloping-like response,while cylinder 3 and cylinder 4(downstream cylinder)present an combined vortex resonance(VR)and wake-induced galloping(WIG)response.When S/D = 2.5～3.0,cylinder 1 and cylinder 2 are basically close to the VIV of a single cylinder except for weak vibration for large reduced velocity.Both of cylinder 3 and cylinder 4 present a separated VR and WIG response with different amplitudes and response regions.At S/D = 4.0,cylinder 1 and cylinder 2 are almost similar with the single cylinder,while cylinder 3 and cylinder 4 still present a separated VR and WIG and the vibration responses between the downstream cylinders are very close.When the cylinder exhibits VIV(upstream cylinder)or VR(downstream cylinder),the vortex shedding frequency fswill significantly be locked to the first harmonic of the natural frequencyfn.As the reduced velocity gradually increases,the cylinders present intense galloping-like response(upstream cylinder)or WIG(downstream cylinder)and the shedding frequencies fsshow distinct multiple harmonics.While,the vibration frequency foonly can be locked to the natural frequency fn.By summarizing the vibration amplitudes characteristics of the four square-arranged and the two cylinders,it can be found that there exist similar vibration patterns among them and the dynamic response law of the two cylinders system are still applicable to the four square-arranged cylinders.
关键词
流致振动/风洞实验/正方形四圆柱/涡激振动/流固耦合Key words
flow-induced vibration/wind tunnel experiment/four square-arranged circular cylinders/vortex-induced vibration/fluid-structure interaction引用本文复制引用
基金项目
国家自然科学基金(12172218)
河南省高等学校重点科研项目(23A130002)
出版年
2024
NETL
NSTL
万方数据