中文摘要：

文章采用基于边界瞬时涡量守候的拉格朗日方法（IVCBC）,结合并列双圆柱的特点,建立了双圆柱绕流数值计算模型。对高雷诺数下Re=6×10~4,间隙率为T/D=1.1~7的并联圆柱双圆柱二维绕流特性进行了研究。提出了双圆柱间隙中点的速度区别宽窄尾流的新方法。分别讨论了流体力系数随间距增加的特点,脉动流体力的特点,尾流特征以及斯托哈尔数特征。研究发现：区别宽窄尾流的新方法是可靠的;在双圆柱尾流附近有五种尾流模型存在;同时发现了在宽窄尾流的频率,存在一个中间频率。

英文摘要：

A novel pure-Lagrangian vortex method based on instantaneous vorticity conserved boundary conditions （ IVCBC） was applied to investigate the hydrodynamic coefficients and patterns of two-dimension-al flow around two circular cylinders in side-by-side arrangements with pitch ratios T/D=1.1-7 at a high4Reynolds number Re=6×10 . The benchmark case of viscous flow around a circular cylinder was first car-ried out to validate the novel vortex method. Then simulations of the flow around two side by side circular cylinders were performed. A new scheme was proposed to distinguish the wide wake （WW） and narrow wake （ NW） byjudging the velocity direction of a specific point in the gap flow. The hydrodynamic coefficients and Strouhal numbers were thoroughly studied as a function of the pitch ratios. A total of five kinds of flow patterns were identified. During the investigation of biased flow, an intermediate frequency between frequen-cies of NW and WW was found and approached to that of a single cylinder. The results show good agree-ment with the previously published experimental and numerical data.