Triple helical strakes have been proved to be highly effective in suppressing the vortex-induced vibration (VIV) of isolated riser. Nevertheless, when risers work in clusters, interference effect can give rise to more complicated flow-induced vibration (FIV) behaviors, which in turn will largely compromise the suppression efficiency of triple helical strakes. In this paper, an experimental investigation on the VIV of two side-by-side risers in a uniform flow was carried out in a combined wave–current water flume. The riser models, with an effective length of 2.0 m and an aspect ratio of 111.11, were placed in the flume with 40% of their lengths immersed in water. The smooth riser was arranged side by side with the triple helical strakes vibration suppression riser with pitch/height of 17.5D/0.25D. By varying the structure and hydrodynamic parameters such as flow velocity and spacing ratio of the straked riser under interference effect and its dynamic feedbacks to the smooth riser for cases of side-by-side configuration are analyzed base on the observed dimensionless displacement, dominant frequency, and modal weight distribution of the risers. The results show that the interference effect of the straked riser on the smooth riser is significant, and the smooth riser with high velocities and large spacing arrangement is more likely to generate higher-order modes; under the influence of interference effect, the dominant frequency of straked riser is close to that of smooth riser, and this phenomenon disappears at high reduced velocities; the interference effect has a significant effect on the vibration suppression efficiency of the three triple helical strakes vibration suppression device. The maximum reduction of CF direction is 14.64%, and that of IL direction is 35.41%.

事实证明，三重螺旋风道可以有效地抑制孤立立管的涡激振动（VIV）。但是，当立管成簇工作时，干扰效应会导致更复杂的流致振动（FIV）行为，进而会严重损害三重螺旋形板条的抑制效率。在本文中，在波浪流水槽的组合中，以均匀流动的方式对两个并排立管的VIV进行了实验研究。将有效长度为2.0 m，长宽比为111.11的立管模型放置在水槽中，将其长度的40％浸入水中。平滑立管与三螺旋螺旋减振立管并排布置，螺距/高度为17.5 D / 0.25 D。在观察到的无量纲位移，主频，和立管的模态重量分布。结果表明，行程冒口对光滑冒口的干扰效果显着，具有较高速度和较大间距的光滑冒口更容易产生高阶模态。在干扰效应的影响下，阶梯状立管的主频接近平滑立管的主频，这种现象在降低的高速度下消失。干扰效应对三个三重螺旋叶片减振装置的减振效率有重要影响。CF方向的最大减少量为14.64％，IL方向的最大减少量为35.41％。