【作者】 张成；

【导师】 王光谦；

【作者基本信息】 清华大学 ， 水利工程， 2008， 博士

【摘要】 南水北调中线工程是一项特大型跨流域调水工程,其渠线长、南北跨度大,供水区域范围广,全程自流输水且无合适的在线调节水库,由此造成的长距离输水水动力学问题,以及水流传播与响应过程十分复杂。总干渠的非恒定流特性与输水过程稳定性及运行控制优化是保证渠道安全稳定输水所要研究的关键问题。本文通过对闸门、倒虹吸等复杂内边界条件进行概化处理,将概化后的内边界条件与明渠圣·维南方程耦合,采用稳定性好、精度高的Preissmann格式进行求解,建立了具有复杂内边界的长距离输水明渠一维非恒定流数学模型,实现了对闸门开度变化引起的不同过流过程的连续模拟。为了实现渠系水流运动和传输过程的模拟和实时表现,利用组件技术构建电子渠道平台的水力学专业模型库,采用多线程的方法将非恒定流数学模型与电子渠道平台相耦合,使电子渠道的基础数据层、平台层和应用层的有机结合起来,形成了输水能力分析、输水过程响应分析的综合平台。利用所建立的南水北调中线工程电子渠道平台的计算模拟模型,对南水北调中线工程的输水安全及稳定性和运行控制优化等关键问题进行了研究。通过模拟计算,分析了正常运行和非正常运行条件下的南水北调中线工程总干渠的非恒定流输水响应现象和特征,得到了正常工况下渠道水深、断面几何尺寸、节制闸的开度变化幅度以及变化速率对渠道稳定时间和水流波动特征的影响关系,拟合出相应的公式;同时也获得了事故工况下,总干渠水位壅高高度和水位降落幅度的特征;在此基础上,计算分析了总干渠按照闸前常水位方式运行情况时,不同允许水位变幅下的水力响应特性,得到了闸前常水位运行方式下中线总干渠的最优水位允许变幅区间,接着提出了区间调度的概念,对区间调度的可行性进行了初步的模拟研究。更多还原

【Abstract】 The Middle Route of the South-to-North Water Diversion Project (MRSNWD) is a large-scale water conveyance project with long channel, large span, wide range of supplied region and all flow automatically without any reservoir along the channel; therefore the hydrodynamic problem of long-route water conveyance and current transmit and response will be very complicated. Characteristic of unsteady-flow in main channel and stability of water conveyance and the best operation control are key problems to insure the channel transmit water safely and stably.In this paper a one-dimensional numerical model was developed for unsteady-flow in a large-scale conveyance channel with complex inner boundary conditions. Generalized equations describing the complex inner boundary conditions such as regulators and inverted siphons were solved together with St. Venant equations by Preissmann method with good stability and high precision in the model. Different flow pattern in different opening of the regulators was continuously simulated. In order to implement the simulation and real-time display of the flow movement and transmission in the channel, module technology was employed to construct the hydraulic model of the MRSNWD Digital Channel; multithreading technique was used to couple unsteady-flow model and MRSNWD Digital Channel. It makes the basic database layer, platform layer and application layer of the MRSNWD Digital Channel combined effectively, and construct a comprehensive platform including the analysis of conveyance ability and hydraulic response.The MRSNWD Digital Channel model was employed to study key problems such as safety and stability of MRSNWD conveyance and optimization of operation control for MRSNWD. The phenomena and characteristic of hydraulic response of unsteady flow in main channel under normal and abnormal working conditions were analyzed. The influence of channel depth, section geometric size and the opening of regulators on the stabilization time of channel and fluctuation characteristic of flow is obtained. The characteristics of water level fluctuation in abnormal working conditions are also obtained. Furthermore, feature of hydraulic response in the main channel of MRSNWD at different water-level intervals under downstream control is analyzed and optimized water-level interval under downstream control is obtained. Finally, space dispatching is proposed and preliminary researched.更多还原