Use of helical strakes for FIV suppression of two inclined flexible cylinders in a side-by-side arrangement
Use of helical strakes for FIV suppression of two inclined flexible cylinders in a side-by-side arrangement
复制标题
使用螺旋列板对并排布置的两个倾斜柔性气缸进行 FIV 抑制
DOI：
10.1007/s13344-018-0034-9
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发表时间：
2018
影响因子：
1.6
通讯作者：
Gao XiFeng
中科院分区：
文献类型：
--
作者：
Xu Wanhai;Zhang Shuhai;Zhou Lidan;Gao XiFeng
在拖曳槽中对倾斜45°的两个并排柔性圆柱体采用螺旋条减少流激振动进行了实验研究。本实验的主要目的是验证被认为是隔振圆柱减振最有效的装置——节距为17.5 d、高度为0.25D的螺旋条是否仍然能很好地降低两个倾斜柔性圆柱并排布置的FIV。实验对质量比为1.90、长径比为350的两个相同的倾斜圆柱进行了振动测试。两缸中心距离为3.0D。通过沿槽内拖曳圆柱模型来模拟均匀流动。拖曳速度范围为0.05 ~ 1.0 m/s，间隔为0.05 m/s。最大雷诺数可达1.6×104。实验研究了两个并排倾斜光滑圆柱体、两个并排倾斜圆柱体系统中只有一个光滑圆柱体装有螺旋条和两个圆柱体都装有螺旋条三种情况。给出并讨论了减速条件下两个并排倾斜圆柱的位移幅值、主导频率、FIV抑制效率和主导模式的变化规律。
The experimental studies on flow-induced vibrations (FIV) reduction of two side-by-side flexible cylinders inclined at 45° by using the helical strakes were carried out in a towing tank. The main aim of the experiment is to check whether the helical strakes with a pitch of 17.5Dand a height of 0.25D, which is considered as the most effective vibration suppression device for the isolated cylinder undergoing vortex-shedding, still perform very well to reduce FIV of two inclined flexible cylinders in a side-by-side arrangement. The vibration of two identical inclined cylinders with a mass ratio of 1.90 and an aspect ratio of 350 was tested in the experiment. The center-to-center distance between the two cylinders was 3.0D. The uniform flow was simulated by towing the cylinder models along the tank. The towing velocity varied from 0.05 to 1.0 m/s with an interval of 0.05 m/s. The maximum Reynolds number can be up to 1.6×104. Three cases were experimentally studied in this paper, including two side-by-side inclined smooth cylinders, only one smooth cylinder fitted with helical strakes in the two side-by-side inclined cylinders system and both two cylinders attached with helical strakes. The variations of displacement amplitude, dominant frequency, FIV suppression efficiency and dominant mode for the two side-by-side inclined cylinders with reduced velocity were shown and discussed.