The distribution of depth-averaged velocity is crucial to many engineering problems. This paper presents an analytical solution for the lateral depth-averaged velocity distribution in a 120° curved channel with asymmetric trapezoidal cross-sections in which the curved flow is not fully developed. The proposed analytical model was derived from the streamwise depth-integrated Reynolds-averaged Navier–Stokes equation, which considers the bed stress, Reynolds stress, secondary flow and local flow acceleration. In addition, practical boundary conditions are proposed to consider the trapezoidal cross-sections with linearly varying side beds and the flow separation at the inner bank near the bend entrance. The analytical solutions using the proposed model were found to be in good agreement with measured data. The main contributions of this study are the development of a conventional analytical model for sophisticated circumstances and the proposal of practical boundary conditions that consider flow separation.

中文翻译：

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弯曲通道横向深度平均速度分布的解析模型

深度平均速度的分布对于许多工程问题至关重要。本文提出了一种120°弯曲通道中横向平均深度速度分布的解析解，该通道具有非对称梯形横截面，其中弯曲流没有完全展开。拟议的分析模型是从流向深度积分的雷诺平均Navier–Stokes方程中得出的，其中考虑了床层应力，雷诺应力，二次流和局部流加速度。此外，提出了实际的边界条件，以考虑具有线性变化的侧床的梯形横截面以及靠近弯道入口的内堤处的流动分离。发现使用所提出的模型的解析解与实测数据非常吻合。