Abstract: In this paper,the influence of channel gcomctric parametcrs on the outer bank cell existing usually near the apex ofbend flows is discussed.The existence of outer bank cell is shown to be related to the shift of the maximum longitudinalvelocity below the

Key words: Channel bends, outer bank erosion, secondary currents

摘要： 在弯曲河道弯顶附近，通常存在一凹岸旋涡．本文首先分析了河道形态参数对这一凹岸旋涡存在的影响，然后说明了这一旋涡的存在与最大纵向流速位于水面以下有关．通过美国FallRiver的实测资料对涡量分量的计算和分析，进一步证实了这一旋涡的存在性．最后，根据上述结果和沿凹岸的边界切力分布，阐明了弯道凹岸冲刷的一般机理．

关键词: 弯曲河道, 凹岸冲刷, 环流