中文摘要：

弯曲型河道水流运动规律及阻力特性在水利工程许多领域中占有十分重要的位置.对正弦派生曲线、梯形断面的连续弯曲型河道开展了物理模型试验,采用日本ACM2-RS型X-Y方向2轴电磁流速计对水流流速进行了测量,并对水流阻力进行了分析.结果表明,弯顶水流纵向时均流速分布接近抛物线型,最大流速点位于上部水面以下,整体上大下小,而顺直过渡段水流纵向时均流速分布最大流速点位于底部,整体上小下大;弯道段纵向垂线平均流速横向分布沿程依次为自由涡、均匀流及强迫涡分布;弯顶中垂线水流横向环流随流量、水深的增大而增大,零流速点的相对水深值大致在0.4～0.6范围以内;弯曲型河道水流阻力系数随着过水断面平均水深、水力半径的增大而增大,随着过水断面宽深比的增大而减小.

英文摘要：

Research on flow structure and resistance in meandering channels is very important in hydraulics and river dynamics.During the flow experiment of meandering channels with sine-generated curve form,the velocity is measured using ACM2-RS 2D electromagnetic current velocity meter made in Japan;and the flow resistance is analyzed.The experiment result shows as follows.The longitudinal time average velocity profile in channel bends is very close to parabolic,the maximum velocity appears below the water surface;but in the straight crossing channels the maximum velocity appears near the bed.The horizontal distribution of depth-average longitudinal velocity along the channel bends are free vertex,uniform flow and forced vertex.The relative depth range of zero circulating velocity in channel bends is about 0.4 to 0.6;and the flow resistance in meandering channels increases with the water depth and decreases with the width to depth ratio of the channels.