Tests for flow induced vibration of a square cylinder were conducted in a water tunnel at different incident angles.Good incident angles to energy absorption were discussed.The effects of stiffness and mass of the system on the flow induced vibration were analyzed and Strouhal numbers at different incident angles were fitted.The results showed that a galloping response is dominant for the system with an incident angle of zero,while a ⅤⅣ response is dominant for the system with a non-zero incident angle;when the flow velocity is lower,a larger incident angle is good for the system to absorb the energy of a ⅤⅣ;when the flow velocity is higher,a zero incident angle is good for the system to absorb energy of a galloping;the amplitude of the flow induced vibration is affected by the system's stiffness and mass,but the frequency of the flow induced vibration is not affected almost by those;when incident angles are 30 and 45,both Strouhal numbers are about 0.14;when the incident angle is 15,Strouhal number is about 0.16.%在自循环水槽进行了正方形截面振子的流致振动试验研究,分析了不同来流角度下的振子响应特征,探讨了有利于能量转换的角度安排,阐释了系统刚度与质量因素对该响应的基本影响,并拟合得到了不同来流角度下的斯特罗哈尔数St.结果表明:来流角度为零条件下的振子响应为驰振主导,而来流角度非零条件下的振子响应为涡激振动主导;低流速时,来流角度大有助于振子对涡激振动能量的汲取,而高流速时,来流角度为零有助于振子对驰振能量的汲取;振动振幅受刚度与质量的影响显著,但频率则几乎不受刚度与质量的影响;来流角度为30°和45°时,St较接近,约0.14,来流角度为15°时,St约0.16.
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