1. State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China;
2. State Environmental Protection Key Laboratory of Estuarine and Coastal Environment, Chinese Research Academy of Environmental Sciences, Beijing 100084, China;
3. National Inland Waterway Regulation Engineering Research Center, Chongqing Jiaotong University, Chongqing 400074, China
Abstract：Secondary flow plays an important role in bend flow simulations. There are numerous models in the literature that consider the secondary flow effects. However, these models have generally been verified through simulating flows in a single bend or meandering channels with weak curvature. These models may not be applicable to channels with strong curvature or natural meandering rivers. This paper presents a model which is applied to two laboratory channel bends, one with strong curvature and the other with curvature varying like a natural river. The results show that the modified model predicts a higher water surface and improves the velocity simulation results. The dispersion terms have the same order of magnitude as the viscous stress term and should not be neglected in flow simulations of meandering channels with strong curvature. In addition, the dispersion term plays an important role in improving the velocity simulation results near the wall. Thus, this model is applicable to flow simulations in meandering channels with similar configurations and is more suitable for simulating the lateral evolution of meandering rivers.
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2016, Vol. 56 
