One-dimensional (1D) models of open-channel flow are efficient for simulating in-channel hydrodynamics over long reaches and time periods, but cannot accurately simulate overbank flows that require two-dimensional (2D) models. The derivation and discussion of the behaviour of the coupling terms for horizontal and vertical coupling of the governing equations of 1D and 2D flow are presented here for the first time. Transfer terms for mass and momentum are introduced. Also, for the first time, the quantification of these transfer terms for the case of an experimental meandering channel with overbank flow is presented. For both coupling methods and relatively high overbank flow depth, the advective momentum transfer exceeded the diffusive momentum transfer. The diffusive momentum transfer has similar magnitude between both coupling approaches. The advective momentum transfer was one order of magnitude higher for the horizontal-coupling approach than for the vertical-coupling approach.

中文翻译：

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关于一维和二维明渠流模型水平和垂直耦合的控制方程

明渠流的一维 (1D) 模型可有效模拟长河段和时间段内的河道内流体动力学，但无法准确模拟需要二维 (2D) 模型的堤岸流。此处首次介绍了对一维和二维流动控制方程的水平和垂直耦合耦合项行为的推导和讨论。引入了质量和动量的传递项。此外，首次提出了在实验性蜿蜒通道与溢流的情况下对这些转移项的量化。 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 对于耦合方法和相对较高的溢流深度，对流动量传递超过了扩散动量传递。两种耦合方法之间的扩散动量传递具有相似的幅度。