| 摘要: |
| 在研究浅水湖泊中沉水植物促淤、降低水体浊度的原理等问题时，已有的泥沙求解公式不适用，难以准确预测泥沙运动趋势及状态，这就要根据影响泥沙运动的水流流态进行分析。象限分析法近年来被用于分析泥沙运动状态。详细阐述了该方法的基本原理，介绍了通过实测离散数据用以分析紊动结构的方法，分析了试验数据，并揭示了沉水植物降低水体浊度的机理，即因为沉水植物的存在，在其冠顶以下形成下扫水流，将泥沙携带向床面，同时下扫水流在近床面处与该处的喷射水流混合，从而降低了自身能量，促使泥沙沉降、淤积。 |
| 关键词: 象限分析法 沉水植物 浅水湖泊 泥沙运动 |
| DOI： |
| 分类号:TV142 |
| 基金项目:上海市科学技术委员会科研计划项目课题(13231203700)；水文水资源与水利工程科学国家重点实验室开放研究基金资助项目（2014492111） |
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| Application of quadrant analysis in analyzing sediment transport in flow with submerged plants |
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PANG Cui-chao1,2
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1.State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing;2.Shanghai Department, Changjiang Company Limited of Survey, Planning, Design and Research, Shanghai
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| Abstract: |
| The existing formulas for calcularing parameters such as incipient velocity, uplifted velocity, stopping velocity of sand and silt carrying capacity, etc. describing pattern of sediment transport are not suitable to studying various problems and are difficult to predict a tendency of sediment movement and to explain the formation of the pattern of sediment transport in the case histories such as sediment deposition and turbidity reduction caused by the submerged plants in the shallow lake. The quadrant analysis method has been applied to analyze the pattern of sediment transport in water flow recently. This paper explains a basic principle of this method and the way of using the method to analyze experimentally the measured discretized data of the turbulent flow structure. The method is applied to analyze the experimental data and explore the mechanism of turbidity reduction casused by the submerged plants. There forms a sweeping flow pattern bellow the canopies and the flow brings the sediment toward the bed surface, then the sweeping flow mixes with the sprinkler flow near the bed surface, thus the mixing process reduces the energy contained in the sweeping flow and promotes sediment deposition. |
| Key words: quadrant analysis method submerged plants shallow lake pattern of sediment transport |
