圆柱两自由度涡激振动的数值模拟研究

Numerical Simulation for Vortex-Induced Vibration of Circular Cylinder with Two Degree of Feedoms

利用自编制的基于松耦合方法的求解气动弹性问题的数值模拟程序,计算了在低雷诺数Re=100条件下圆柱的两自由度涡激振动,涡激振动系统的折减阻尼比M*ξ=0.020 8.结果表明,随着折减风速的增加,振动系统依次经历以流向涡激振动和以横向涡激振动为主导的两个锁定区域.结合笔者以前关于圆柱单自由度横向涡激振动的研究工作,考察了流向自由度对横向涡激振动的影响.结果表明,在低雷诺数和低折减阻尼条件下,流向自由度对横向自由度的涡激振动基本没有影响,从而验证了已有的基于实验研究的结论.

By virtue of the code for the aeroelastic problems featured by the loosely coupled method and designed by the authors, the vortex-induced vibration of circular cylinder with two degree of freedoms （2DOFs） at Reynolds number of Re = 100 which has the reduced damping parameter of M^＊ξ= 0. 020 8 was simulated. With the increasing of the reduced velocity, there exist two synchronization regions where the streamwise and the lateral vortex-induced vibration sequentially dominate the sprung system. The effects of the streamwise DOF on the lateral vortex-induced vibration was studied in combination with the previous work about the lateral vibration of circular cylinder with single DOF （SDOF）. The result shows that the streamwise DOF has little effect on the lateral vibration and conforms to the already existed experimental findings.