摘要: |
水位和流速是人工湖维持生态的关键因子,为探究人工湖水位对流速分布的影响,基于二维水动力模型对雁鸣湖流场进行数值模拟,研究单因素水位对流速影响和实测换水水位对流速时空分布的影响。结果显示:水位是水动力影响因素之一,低水位时的湖泊流速大于高水位时期,水位变化时的平均流速介于高低水位流速之间,水位对环流影响较小。在实测换水期间,高水位时水位分布无明显差异,水深自上游至下游逐级递增;低水位时水位分布出现差异,河滩裸露,水深分布差异较大;水位变化时,湖泊上游至下游水位呈梯度变化,水深随水位变化;流速时空分布验证了单因素水位对流速的影响,并表明不同水位对流速大小及分布影响有所差异。雁鸣湖水位和流速的模拟结果表明,人工湖水位变化能改善湖泊水动力,可为人工湖水情管理提供科学参考。 |
关键词: 人工湖 数值模拟 水位 流速 |
DOI: |
分类号:X524; X143 |
基金项目:国家自然科学基金资助项目(51679191); 陕西省水利厅科技计划项目(2016slkj 13); 陕西省教育厅重点实验室科研计划项目(17JS102) |
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Influences of water level on flow velocity distribution during dynamic water exchange in urban artificial lake |
ZHAO Zhengwen1, FENG Minquan1, CHENG Gang1,2, TANG Yang1
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1.State Key Laboratory Base of Eco-hydraulics in Northwest Arid Region of China, Xi’an University of Technology, Xi’an;2.Xi’an Water Conservancy Survey and Design Institute, Xi’an
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Abstract: |
The water level and flow velocity are the key factors in maintaining and improving the ecological environment of the artificial lakes. In order to study and analyze the influences of the water level upon the flow velocity distribution, the numerical simulations of the flow field of the Yanming Lake are carried out based on a two-dimensional hydrodynamic model. And the simulations include the influences of a single-factor water level on the flow velocities and the influences of the measured level of exchanged water on the temporal and spatial distribution of the flow velocities during water level fluctuation. The simulated results indicate that the water level is one of the factors influencing hydrodynamics, and the flow velocity in the Yanming Lake is greater than that during high water level and distribution. In addition, as the water level falls and rises, there is a little influence on the circulation. During the water exchange, there is no obvious difference in the water level distribution in the high water level periods; the water depth increases progressively from the upstream to the downstream. In the low water level periods, the water level distribution is different, the flood plain is exposed, and the water depth distribution varies greatly. When the water level changes, the water level from the upstream to the downstream of the Yanming Lake shows a gradient change, and the water depth varies with the water level; and the spatial and temporal distribution of the flow velocities verifies the impacts of the single-factor water level on the flow velocities, and it is also shown that the different water levels have different effects on the flow velocities and the flow velocity distribution. The numerical simulation analysis results show that the water level of the artificial lakes can improve their hydrodynamics, and can provide scientific references for their regime management. |
Key words: artificial lake numerical simulation water level flow velocity |