采用大涡模拟方法(LES)对低雷诺数均匀来流中串列圆盘绕流问题进行了模拟,主要研究圆盘间距对尾迹的影响.研究发现当两圆盘间距足够小时,流场Hopf分叉相对于单个圆盘推迟.选取雷诺数为200,对圆盘间距l/d分别为1,1.5,2,3和6时的串列圆盘绕流进行模拟,发现当l/d=1时,尾迹为稳态面对称结构;l/d=1.5时,尾迹为非稳态面对称结构;l/d=2时,尾迹面对称结构破坏;l/d=3时,上游圆盘尾迹恢复面对称;l/d=6时,两个圆盘尾迹均恢复面对称.
A large eddy simulation(LES) was conducted to investigate the uniform flow over tandem disks at low Reynolds number, mainly focusing on the influence of separation distance on wake structure.The results show that the Hopf bifurcation of flow field is delayed compared with that of a single disk when the distance between the two disks is small enough.The research was performed at Re = 200 with distances l/d = 1,1.5,2,3 and 6, respectively. It is concluded that the wake is stable and plane-symmetrical at l/d = 1 and unstable but plane-symmetrical at l/d : 1.5. At l/d = 2, the plane-symmetrical structure is broken.The upstream wake resumes plane-symmetry at l/d =3 while the wake of both disks resume plane-symmetry at l/d=6.