雅鲁藏布江桑日河段河床演变数值模拟研究

发布时间：2018-04-08 14:01

本文选题：雅鲁藏布江　切入点：EFDC　出处：《重庆交通大学》2016年硕士论文

【摘要】：近年来随着国家西部开发战略的实施,青藏高原地区与全国的交流日益密切,随着青藏高原地区的发展,对于雅鲁藏布江的开发利用也要快速增多。但是由于对于雅鲁藏布江的河床演变研究的资料较少,制约了雅鲁藏布江的开发利用,所以研究雅鲁藏布江的河床演变对河流的开发利用有着十分重要的意义,而且也为以后的对雅鲁藏布江的研究提供参考。本文选取雅鲁藏布江的桑日河段作为研究河段,通过EFDC建立桑日河段的三维的水沙非耦合数学模型,对桑日河段的河床演变进行数值模拟研究。主要内容包括:(1)通过实测资料,分析对比河道断面的变化,讨论雅鲁藏布江桑日河段的近期河床演变规律。分析可知:河段上部分河床变化剧烈;中段以及下段河势较为稳定。(2)介绍数学模型的建立过程,控制方程的离散求解,而且对在方程求解过程中所需使用的各个参数进行设置。(3)建立三维水动力模型,计算得到各个频率洪水下的水流条件,分析计算得到的结果。计算表明:上游河段为流速、比降较小的河段,中段流速、比降较大,泥沙不容易落淤,河段下段主流流速迅速降低,深泓线陡然下降,上游输移下来的泥沙将会沉积。(4)建立三维的水沙数学模型,在研究泥沙的输移问题时,将先对悬移质和推移质进行单独分析,研究悬移质在洪水流量下的输移规律,以及推移质输沙带的分布,最后再模拟河段长时间的河床演变,对桑日河段的河床演变提出长期预测。结果表明,桑日河段上段和下段总体河床演变趋势均为淤积,中段急弯处年内冲淤变化较大。
[Abstract]:In recent years, with the national implementation of the western development strategy, Qinghai Tibet Plateau and the increasingly close exchanges, with the development of the Tibetan Plateau, for the development and utilization of the Yarlung Zangbo River have increased rapidly. But due to the Brahmaputra River riverbed evolution research material less, restrict the utilization of Brahmaputra River, so the development and utilization of study on the evolution of the river Brahmaputra River has a very important significance, but also provide reference for research on the Brahmaputra River in the future. This paper selected as the research section of the Yarlung Zangbo River, river water, three-dimensional mathematical model of the Sha Fei by EFDC, research of numerical Simulation on the evolution of SANGRI river bed. The main contents include: (1) based on the measured data, analysis of the changes of river section comparison, discussion on the Mulberry River Brahmaputra The river bed evolution. Analysis shows that the river part of the river bed changes sharply; the middle and lower section of the river regime is relatively stable. (2) describes the process of establishing the mathematical model, the discrete equations are solved, and the various parameters required for use in the process of solving the equation set. (3) the establishment of three-dimensional hydrodynamic model the calculated flow conditions, each frequency of flood, the analytical results obtained. Calculation results show that: the upper reaches of the river is smaller than the velocity, lower reach, middle velocity gradient is larger, not easy to sediment silting, the river section of the mainstream velocity decreases rapidly, thalweg precipitously, sediment deposition upstream will transport down. (4) to establish mathematical model of sediment transport problem in 3D, sediment research, will be the first suspended and bed were analyzed separately, the research of suspended sediment transport in the flood displacement law of flow, and bedload transport With the evolution of distribution, and finally reach the long time simulation of river bed, SANGRI river bed change proposed long term prediction. The results show that the upper and lower reaches of the evolution trend of the whole section of river bed is silt, silt at middle bends changed greatly during the year.

【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TV147

【相似文献】