| 摘要: |
| 【目的】研究抚仙湖沿湖湿地建设（计入湿地综合糙率）对湖泊水流流场的影响，为水质模拟研究提供基础。【方法】在生态水槽试验中，分别研究了3种不同高度水草在3种流量下的水力特性，得到植物水流综合糙率与植物高度的关系。以此为基础，建立了计入湿地综合糙率的抚仙湖二维水动力模型，模拟计算了抚仙湖水体（方案1）、拓展水域后水体（方案2）及在拓展水域内建设湿地后总水体（方案3）的水流流场，分析了拓展水域及建设湿地对抚仙湖流场的影响。【结果】拓展水域对抚仙湖的整体流场影响较小，然而拓展水域改变了局部边界条件，使局部区域的流速增加，如北岸区域平均流速增大52.65%，原抚仙湖水体的平均流速仅增加2.10%。湿地建设对流场的影响主要体现在湿地区域，而对抚仙湖的整体流场影响较小，如南岸湿地区域平均流速比方案2减小了68.20%，原水体的平均流速仅减小了4.11%。【结论】计入湿地综合糙率的沿湖湿地建设对抚仙湖原水体流场影响较小，可为下一步水质模拟研究提供理论基础。 |
| 关键词: 抚仙湖；湿地；综合糙率；水动力模型；流场 |
| DOI：10.13522/j.cnki.ggps.2021596 |
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| 基金项目: |
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| Simulating the Impact of Wetland Construction on Flow Velocity in the Lake Fuxian with the Comprehensive Roughness Considered |
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CHENG Haoliang, YANG Jurui
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1. School of Civil Engineering, Southwest Forestry University, Kunming 650224, China;
2. Faculty of Civil Engineering and Mechanics, Kunming University of Science and Technology, Kunming 650000, China
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| Abstract: |
| 【Objective】The influence of wetland construction considering the comprehensive roughness on flow velocity field of Lake Fuxian was studied to provide the premise for water quality simulation. 【Method】The study was based on numerical simulation by taking the Lake Fuxian as an example. In the ecological water channels, the retarding effect of three types of plants with different heights on water flow was simulated under different flow rates. We considered the comprehensive roughness and calculated the relationship between the comprehensive roughness and plant height, from which we established a two-dimensional hydrodynamic model with the comprehensive roughness of the wetland considered to simulate the flow velocity in the lake. The modelling compared three schemes: existing waterbody, expanded waterbody by removing the breakwater, and whole waterbody after construction of the wetland. The effects of the wetland plants and the expanded waterbody on the flow velocity fields were analysed.【Result】Expanding the waterbody changed the boundary conditions of the local water, increasing the magnitude of flow velocity in the local water while having little impact on water velocity in other areas. In the north shore, the averaged flow velocity was increased by 52.65%, while in the original region, the averaged flow velocity was increased only by 2.10%. The wetland impacts flow field mainly in the wetland area, with the average flow velocity in the south shore decreasing by 68.20%, compared with the expanded waterbody. In the original region, the averaged flow velocity was decreased only by 4.11%.【Conclusion】The constructed lakeside wetland has little impact on original water flow velocity field in the Lake Fuxian even with the comprehensive roughness considered. The method and results presented in this paper can help to design artificial wetlands. |
| Key words: Lake Fuxian; wetland; comprehensive roughness; hydrodynamic model; flow velocity field |
