高雷诺数时分离盘长度对圆柱绕流特性的影响

发布时间：2018-05-25 17:10

  本文选题：圆柱体 + 分离盘　； 参考：《上海交通大学学报》2017年04期

【摘要】：使用大涡模拟方法,研究了高雷诺数时分离盘长度对圆柱绕流特性的影响,对不同长度分离盘下作用在圆柱体上的升力系数、拖曳力系数以及尾部流场的无量纲漩涡泄放频率(strouhal数)以及漩涡泄放形态进行了对比分析.分析结果表明:依据升力系数以及拖曳力系数随时间历程的变化特性可以将分离盘长度大致划分为3个区间,分别为稳定区间Ⅰ(分离盘长度L=0D时,D为圆柱直径)、非稳定区间Ⅱ(L=0.5D-1.0D)以及再稳定区间Ⅲ(L=1.5 D-8.0D).当分离盘长度从区间I变化到区间Ⅱ时,Strouhal(Sr)数出现突降;当分离盘长度从区间Ⅱ变化到区间Ⅲ时,Sr出现突升.随着分离盘长度的增加,圆柱尾部流场的漩涡泄放形式从2S模式(即从圆柱两侧每次只泄放单个漩涡)逐渐转化为2P模式(即从圆柱两侧每次同时泄放2个漩涡).
[Abstract]:In this paper, the influence of the separation disk length on the flow characteristics around a cylinder with high Reynolds number is studied by means of large eddy simulation, and the lift coefficient of the cylinder acting on the cylinder with different lengths is studied. The drag force coefficient and the dimensionless vortex release frequency (strouhal number) of the tail flow field are compared and analyzed. The results show that according to the variation characteristics of lift coefficient and drag force coefficient with time history, the length of separation disk can be roughly divided into three regions. They are stable interval 鈪，

本文编号：1934006