【作者】 赵万星；

【导师】 陈景秋；

【作者基本信息】 重庆大学 ， 工程力学， 2005， 博士

【摘要】 模拟和预测环境流体中物质的混合和输运过程是环境管理中的一个重要环节。河流的动力特点和物质输运能力直接关系到河流的自净能力。三峡水库建成后,重庆主城区河段处于水库变动回水区的中上段,其水动力条件和物质输运能力将发生巨大变化。本文主要内容是针对重庆主城区河段的水环境管理、城市防洪和饮用水的采集等实际问题进行了环境流体动力学研究,这对于三峡工程的环境安全也是极为重要的研究,并且为三峡库区水环境的研究提供了一个有力的服务工具。因而本研究具有重要的科学意义和实际意义。本文工作主要以长江、嘉陵江重庆河段的水环境动力研究为目的,针对这类山区河流地形变化剧烈,水位涨落大,流速变化大的特点,建立相应的三维非定常流数值模型,并利用该模型研究重庆水环境变化的规律。前三章的内容是河流数值模拟的理论部分,后三章内容是数值模型在河流研究中的应用,包括西江航道整治的研究、重庆两江汇流段水动力的研究和重庆主城区河段水环境的研究。在前两个模型的成功应用的基础上,本文建立了重庆主城区河段模型并成功应用于模拟重庆两江河段的流场、浓度场和漂浮物运动。第一章提出本文工作的目的和方法,论述河流数值模拟的难点和回顾有关研究现状。第二章讨论浅水流理论和水质模型。浅水波假设符合大多数河流问题,其理论主要有Airy理论和Boussinesq理论两类。稳定而精度高的数值方法可以较为真实地反映物理现象和过程。应用有限体积法,建立了河流水质模型-嘉陵江石门段水质模型并完成了水质模拟。第三章建立了一个三维非定常流的河流数值模型。水平面采用正交贴体网格,垂向采用σ坐标,引进了静水压近似和Boussinesq近似后,采用内外模式分裂法求解动量方程和连续方程,耦合求解流场和浓度场,紊动模型采用Mellor-Yamada模型。在数据的处理上,模型建立了专门的可视化软件。第四章建立了西江四滩的悬浮物模型并应用于该河段的航道整治工程结果的预测。西江悬浮物模型模拟了复杂边界条件下的非定常水沙运动,以及河床冲淤过程。模拟的结果体现了模型在地形复杂,水流多变的河流研究中的应用能力,表明模型适用于处理运动边界、动床边界和悬沙运动,适于模拟弯道环流、绕流等流态。西江模型的建立和应用可以为动力条件相似的重庆河段的研究打下了基础。第五章针对重庆河段复杂的两江汇流问题,建立两江汇流段水动力模型。模更多还原

【Abstract】 The ability to simulate and predict the transport and mixing of materials discharged into the water body is an essential element in environmental management. After the running of Three Gorges Reservoir, the reaches of Yangtze River and Jialing River in the city Chongqing become the middle and upper reach of the fluctuating backwater reach of Three Gorges Reservoir, and their hydrodynamic conditions will be changed greatly. A 3D model for the water environmental management, flood control and drinking water source safety in the reaches of Yangtze River and Jialing River in the city Chongqing is developed, and the significant work to the environmental safety has been done in this dissertation. The model constructed here is a powerful tool to study the environmental fluid dynamics of Three Gorges reservoir.The environmental fluid dynamics of Yangtze River and Jialing River in Chongqing city is the main content of this dissertation. A 3D environmental fluid dynamics model is developed. Using this model, the flow with complex topographies, complicated boundaries and a lot of nonlinear processes can be simulated accurately. The environmental problems of Yangtze River and Jialing River in Chongqing are analyzed. The text is arranged as follows: The theoretical part of numerical simulation is present in Chapters 1,2,3; and the applications of the river model are described in Chapters 4,5,6, including the channel regulation project in Xijian River, the hydrodynamic of the confluent reach of Yangtze River and Jialing River and the environmental research of the reaches of Yangtze River and Jialing River in the city Chongqing. After the successful applications of the first two models, the environmental model for the whole reaches of Yangtze River and Jialing River in the city Chongqing is developed, and based on this model, the numerical simulation of the flow field, material concentration field and drifter’s motion is carried out.The main aims and methods of this dissertation are put forward in Chapter 1. The issues of river simulation are discussed, and the development of the researches about river models is reviewed.The shallow water theories and water quality models are discussed Chapter 2. Airy theory and Boussinesq theory are two kinds of the main methods. The development of more accurate and more stable computational techniques is helpful to understand and predict environmental fluid flows. Using FVM, a water quality model of Shimen reach更多还原