This paper demonstrates the influence of differential roughness on the boundary shear distribution for compound open channels. A mathematical relationship is derived between the percentage shear force carried by floodplains and five non-dimensional parameters (width ratio, relative flow depth, relative roughness, Reynolds number and Froude number). A procedure for assessing the flow distribution in terms of zonal boundary shear distribution and momentum transfer coefficients at the junction of a compound channel is presented. The efficiency of the model was tested by comparisons with published datasets and large experimental flood channel facility datasets. Compared with other standard approaches, the proposed method provided the least error in the predictions of both boundary shear and flow. The approach was also verified using actual river data and was found to provide good predictions in real-world applications.

中文翻译：

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具有不同粗糙度的复合通道中的边界剪切分布

本文演示了差异粗糙度对复合明渠边界剪切分布的影响。洪泛区所承受的剪切力百分比与五个无量纲参数（宽度比，相对流深，相对粗糙度，雷诺数和弗洛德数）之间存在数学关系。提出了一种根据区域边界切变分布和复合通道交界处的动量传递系数评估流量分布的程序。通过与已发布的数据集和大型实验洪水通道设施数据集进行比较，测试了模型的效率。与其他标准方法相比，该方法在边界剪力和流量的预测中提供了最小的误差。