刚性联结串列双圆柱尾流致涡激振动研究

Investigation on wake-induced vibration of two rigidly coupled circular cylinders in tandem arrangement

为了研究刚性联结对串列双圆柱尾流致涡激振动的减振效果及其流场作用机理,以圆心间距为4D(D为圆柱直径)的无联结及刚性联结串列双圆柱为研究对象,在雷诺数Re=150时,采用数值模拟方法研究了刚性联结对圆柱振幅、振动轨迹和锁振区域的影响规律,分析了振动响应和气动力之间的内在联系,探讨了两类圆柱振动差异背后的流场机理。研究表明:刚性联结对串列双圆柱的尾流致涡激振动有一定的减振作用,提高了发生涡激振动的起振风速,减小了发生涡激振动的折减速度范围,降低了下游圆柱的振幅,但上游圆柱振幅略有增加。发生尾流致涡激振动时,无联结串列双圆柱和刚性联结串列双圆柱的的流固耦合机制不同,两者的尾流模态有很大差异。

To investigate the damping effect of the rigid connection on the wake-induced vibration of two tandem circular cylinders,the wake-induced vibration of two uncoupled and rigidly coupled tandem circular cylinders are simulated at a low Reynolds number of 150,with a center spacing of 4D(D is the diameter of the cylinder).The influence of rigid connection on the vibration amplitudes,trajectories and lock-in regime of the cylinders are investigated.The relationship between the vibration amplitudes and the aerodynamic forces is analyzed.The flow mechanisms of the wake-induced vibration of two types of tandem cylinders are discussed.It is found that the rigid connection has a significantly inhibitory effect on the wake-induced vibration of two tandem circular cylinders.The rigid connection increases the reduced velocity when the amplitude starts growing quickly,narrows down the lock-in regime,and reduces the maximum amplitude of the downstream cylinder.However,the maximum amplitude of the upstream cylinder is increased slightly.The fluid-structure interaction and the wake modes of two uncoupled and rigidly coupled tandem circular cylinders are different.