Numerical Simulation of Effects of Sediment Supply on Bedrock Channel Morphology
Numerical Simulation of Effects of Sediment Supply on Bedrock Channel Morphology
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DOI：
10.1061/(asce)hy.1943-7900.0001124
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发表时间：
2016-03
影响因子：
2.4
通讯作者：
Takuya Inoue;T. Iwasaki;G. Parker;Y. Shimizu;N. Izumi;C. Stark;J. Funaki
中科院分区：
文献类型：
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作者：
Takuya Inoue;T. Iwasaki;G. Parker;Y. Shimizu;N. Izumi;C. Stark;J. Funaki
天然基岩河流具有多种侵蚀形态。虽然在以前的研究中已经注意到基岩上交替沙坝的形成，但这些交替沙坝对基岩侵蚀的影响尚未阐明。在这项研究中，作者提出了一个模型，再现砂坝形成和侵蚀形态的冲积河流。此外，作者报告的数值模拟，以评估沉积物供应的影响，在基岩表面和以上的床的状态。数值结果说明了不同的形态形成不同的供应率。当供沙率接近输沙量时，形成冲积-基岩交错沙坝。这些沙坝类似于纯粹的冲积交错沙坝。一条蜿蜒的冲积物线在均匀侵蚀的基岩表面上向下游迁移。当泥沙供应量远低于能力时，在河床上形成多个切槽（槽）。
AbstractNatural bedrock rivers exhibit diverse erosional morphologies. Although the formation of alternate bars on bedrock has been noted in previous studies, the influence of these alternate bars on bedrock erosion has not been clarified. In this study, the authors propose a model for bedrock-alluvial channels that reproduces both bar formation and erosional morphology. In addition, the authors report on numerical simulations to evaluate the influence of sediment supply on the state of the bed at and over the bedrock surface. The numerical results illustrate the formation of different morphologies for different supply rates. When the sediment supply rate is close to transport capacity, mixed alluvial-bedrock alternate bars form. These bars are analogous to purely alluvial alternate bars. A meandering thread of alluvial material migrates downstream over a uniformly eroding bedrock surface. When the sediment supply rate is well below capacity, however, multiple incisional troughs (grooves) form on the bedr...