变水头无压输水隧洞水流特性及洞内消能研究

发布时间：2018-06-26 19:50

本文选题：变水头 + 无压隧洞　；参考：《大连理工大学》2014年硕士论文

【摘要】：在我国,水资源存在分布不均的现象,不仅南北、东西存在严重水资源的差异,而且即是同一个地区也存在水资源分布不均的现象。加之近些年来生态环境遭到严重破坏,水体污染严重,水资源紧缺的问题越来越成为社会关注的热点。因此兴建水利设施成为调整水资源分布解决水资源短缺的重要手段。水利工程中引水隧洞是最主要的输水建筑物,引水隧洞分为无压输水隧洞和有压引水隧洞。引水隧洞在运行过程中经常会遇到流态紊乱、流速过大、空蚀空化、明满交替、流激振动等水力学问题,因此在引水隧洞设计时,均需要考虑隧洞内部水流特性和消能问题,这对于引水隧洞正常的运行以及对整个工程的安全至关重要。本文以引水工程为背景作为研究对象,主要采用物理模型试验的方法进行无压输水隧洞在变水头条件下水流特性及消能的研究。本工程无压输水隧洞水流特性主要有以下几个特点,水头高,变幅大,洞内流速大,闸门调度复杂,洞内的消能工布置困难。模型试验研究过程中,通过在变水头条件下进行闸门调度和测量洞内流速、水面线、压力等水力因素来研究无压引水隧洞的水流特性。同时对于无压输水隧洞的消能,突破常规的洞外出口消能,而采取洞内布置消能工的方式进行消能。试验研究过程中,隧洞内部消能工采用消力池形式进行消能研究。通过对消力池进行优化设计,改善了隧洞内部的水流流态,达到了一定的消能效果,满足了工程的要求。本课题在模型试验的基础上针对变水头条件下无压输水隧洞水流特性和洞内消能两方面进行了初步研究,其成果可以为该工程的设计提供依据,同时也为类似工程设计提供参考。
[Abstract]:In China, there is a phenomenon of uneven distribution of water resources, not only in the north and south, but also in the east and west, and even in the same area there is a phenomenon of uneven distribution of water resources. In addition, in recent years, the ecological environment has been seriously damaged, the water pollution is serious, and the water resources shortage has become the focus of social attention. Therefore, the construction of water conservancy facilities has become an important means to adjust the distribution of water resources to solve the shortage of water resources. Diversion tunnel is the main water conveyance structure in water conservancy engineering. The diversion tunnel is divided into pressure free water diversion tunnel and pressure water diversion tunnel. In the course of operation, the diversion tunnel often encounters some hydraulic problems, such as turbulent flow pattern, excessive velocity, cavitation, alternating open and full flow, fluid-induced vibration and so on. Therefore, in the design of the diversion tunnel, it is necessary to consider the characteristics of water flow and energy dissipation in the tunnel. This is very important for the normal operation of the diversion tunnel and the safety of the whole project. In this paper, based on the background of water diversion project, the physical model test method is used to study the flow characteristics and energy dissipation of the pressure free water conveyance tunnel under the condition of variable water head. The characteristics of water flow in the unpressurized water conveyance tunnel of this project are as follows: high water head, large amplitude of variation, large velocity of flow in the tunnel, complex gate dispatching and difficult arrangement of energy dissipators in the tunnel. In the course of model test and research, the flow characteristics of unpressurized diversion tunnel are studied by the hydraulic factors such as velocity, water surface line, pressure and so on, which are controlled by gate and measured under the condition of variable head. At the same time, the energy dissipation of the unpressurized water conveyance tunnel breaks through the conventional outlet energy dissipation outside the tunnel, and the energy dissipation is carried out by the arrangement of energy dissipators in the tunnel. In the course of experimental study, the energy dissipation in tunnel is studied in the form of dissipation pool. By optimizing the design of the stilling pool, the flow pattern in the tunnel is improved, the energy dissipation effect is achieved and the engineering requirements are met. On the basis of the model test, this paper makes a preliminary study on the flow characteristics and energy dissipation of the unpressurized water conveyance tunnel under the condition of variable head, and the results can provide the basis for the design of the project. At the same time, it also provides reference for similar engineering design.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV135

【参考文献】