Abstract: The circumfluence around columns of plane potential flow was studied based on the theory of functions of a complex variable，and the analytic solution was educed and analyzed．When L/a>3，the muttual interference disappears between cofferdams．In order to prevent cofferdam from heavy scouring，the cofferdam shelter should be placed 0.75 a away from cofferdam.For preventing sailing ship from colliding the cofferdam under the effects of coferdam circling flow。the guard fence around the cofferdam should be installed at 0.5L from upper reaches．For reducing the movement of circumfluence．the ≤5between ge and current axes is advised．

Key words: steel cofferdams, flow past body model, complex function, curent structure

摘要： 运用复变函数理论研究了理想液体平面势流的多圆柱绕流，导出了多圆柱绕流的解析解，并对其特殊解进行分析，得出当L／a>3时多圆柱间相互干扰消失；为防止围堰发生过大冲刷，应在距围堰0．75a范围内防护；防止发生的围堰绕流对行船产生影响，避免轮船对围堰的撞击影响施工进度和质量，应在上游距桥址>0．5L处设置防撞栏；避免绕流流线变化过大，桥轴线方向与水流流速方向夹角一般应控制在 ≤5。．

关键词: 钢围堰群, 绕流模型, 复变函数, 水流结构