柔性分离盘抑制圆柱涡激振动的风洞试验

Wind tunnel experiment of VIV control on circular cylinder with flexible splitter plate

该文利用附属柔性分离盘对圆柱涡激振动(VIV)控制问题进行了风洞试验研究。针对弹性支撑的圆柱及不同长度柔性分离盘的试验模型,在雷诺数7 500-40 000情况下,测定不同约化速度(3.5-18.7)下的振动瞬态位移。结果表明:柔性分离盘长度(L)/圆柱直径(D)比为0.6、0.8和1三种圆柱的横向无因次均方根振幅远小于单圆柱,涡激振动抑制效果很好,均在77.6%以上,其中L=0.8D的圆柱抑制效果最佳,几乎无振动;而L=1.2D和1.5D的圆柱反而出现振动增强,约4.5%和9%。对比单圆柱的共振区,附属柔性分离盘的圆柱共振区在约化速度上更靠后且范围更大。

This paper performed a wind tunnel experiment on the suppression of vortex-induced vibration （VIV） for a circular cylinder with flexible splitter plates of five different lengths. The transient displacement of the flexibly mounted cylinders with flexible splitter plates at the Reynolds numbers from 7 500 to 40 000 （the reduced velocity is from 3.5 to ! 8.7） was measured. It shows that in the cross-flow direction the root-mean-square response amplitudes of cylinders with flexible splitter plates for the length of 0.6 D, 0.8 D and 1 D, are far less than those of a bare cylinder. The suppression effects are all over 77.6%. The cylinder with flexible splitter plate of 0.8 D long scarcely vibrates, which has the best suppression effect. But the cylinders with 1.2 D and 1.5 D long plates vibrate more obviously with increasing amplitude about 4.5% and 9%, respectively. Compared with the resonance region of bare cylinder, the resonance region of cylinders with flexible splitter plates appears later and larger towards the reduced velocity.