无闸低坝枢纽引航道水流条件数值模拟

发布时间：2018-01-18 12:16

本文关键词：无闸低坝枢纽引航道水流条件数值模拟　出处：《重庆交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：近年来，为解决一些河段内泥沙、灌溉取水以及通航条件等问题，无闸低坝水利枢纽这一方案被越来越多的采用。无闸低坝水利枢纽主要作用是抬高上游水位、拦蓄泥沙，其特点主要在三个方面：泄洪道无闸门，水流过坝为自由溢流，来流量等于下泄流量；坝高小，小流量下尚能形成库，大流量下作用更类似于潜坝；规模较小，船闸建筑物缩窄河道的比例较大，流量较大时来流受引航道顶托后口门区横向流较强。因为它这些特点使得其上游引航道水利条件复杂，对通航不利。因此，分析无闸低坝水利枢纽引航道水流条件复杂的成因并对改善措施进行研究显得非常必要。本文在系统总结了各种引航道改善措施研究现状及水流数学模型发展的基础之上，根据福建闽江水口水电站坝下水位治理工程的实测地形、水文资料以及枢纽整体水工物理模型试验所得结果，建立了基于有限元法的能够较为准确地模拟复杂引航道边界条件的平均水深二维水流数学模型对水口水电站坝下水位治理工程的引航道进行改善研究。本文的主要结论如下： ①通过将所建立的二维数学模型与水工物理模型实测资料的进行对比验证，结果表明此数学模型得到的水位、流速及流向与实测资料较为接近，说明二维水流数学模型的建立、数值计算方法以及各参数的设定较为合理，，能够较为准确地模拟实际河道及引航道的水流。 ②针对引航道口门区横向流速过大的问题，提出了引航道透空式导航墙边界处理方法，能够较好模拟透空式导航墙对引航道水流条件的改善情况。 ③通过对水口水电站坝下水位治理工程坝上河段进行分析，总结归纳出致使其上游引航道水流条件复杂的原因。 ④通过数值模拟计算分析研究，提出了延长隔流墙、增加带不同底孔大小的导航墙、增加隔流墩等改善措施，使通航最大流量提升到12000m3/s。
[Abstract]:In recent years, in order to solve some problems such as sediment, irrigation and navigation conditions, the project of low dam without sluice is used more and more. The main function of low dam without sluice is to raise the upstream water level. The characteristics of sediment storage are mainly in three aspects: there is no gate in spillway, the flow of water through the dam is free overflow, the coming discharge is equal to the discharge; The dam height is small and the reservoir can be formed under the small discharge, and the action under the large discharge is more similar to that of the submersible dam. The scale is small, the proportion of the ship lock building narrows the river channel is larger, when the discharge is larger, the transverse flow in the entrance area after the top support of the approach channel is stronger, because of these characteristics, the water conservancy condition of the upstream approach channel is complicated. Therefore, it is necessary to analyze the complex causes of the flow conditions in the approach channel of the low dam water conservancy project without gates and to study the improvement measures. On the basis of systematically summarizing the research status of various approaches to improve waterway and the development of mathematical model of water flow, this paper bases on the measured topography of water level control project under dam of Fujian Minjiang River Hydropower Station. The hydrological data and the result of hydrophysical model test of the whole hydro-engineering of the hub. Based on finite element method (FEM), a 2-D mathematical model of average depth of water flow is established, which can simulate the boundary conditions of complex approach channel accurately to improve the approach channel of the water level control project under the dam of Shuikou Hydropower Station. The main conclusions of this paper are as follows: The results show that the water level, velocity and flow direction obtained by this mathematical model are close to the measured data. It shows that the establishment of two-dimensional flow mathematical model, the numerical calculation method and the setting of each parameter are more reasonable, which can accurately simulate the actual channel and approach channel flow. (2) aiming at the problem of excessive transverse velocity in the entrance area of the approach channel, a boundary treatment method for the permeable navigation wall of the approach channel is proposed, which can better simulate the improvement of the flow condition of the approach channel by the permeable navigation wall. Through the analysis of the water level control project under the dam of Shuikou Hydropower Station, the reasons for the complex flow conditions in the upstream approach channel are summarized. (4) through numerical simulation and analysis, it is proposed to extend the barrier wall, increase the navigation wall with different bottom hole sizes and increase the baffle piers, so as to increase the maximum navigable flow to 12 000 m3 / s.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U612.23

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