白鹤滩水电站取水口流场及下泄水温研究

发布时间：2018-03-11 00:08

  本文选题：势流分析　切入点：物理模型实验　出处：《浙江大学》2014年硕士论文　论文类型：学位论文

【摘要】：水电站取水口诱导流场对库区鱼类卷吸风险评估具有重要意义,流场与温度分布直接影响水库下泄水温。白鹤滩水电站位于金沙江下游,左右岸均设有9个取水口,左岸设有3个泄洪洞。本文以该水电站为研究对象,通过研究不同工况下取水口上游流场分布,总结了水动力学特征、计算出鱼类卷吸风险区域的范围,并在给定的温度分层条件下模拟计算取水口下泄水温。本文首先讨论了左岸取水口上游水动力学要素特征,并评估了各模拟工况下的鱼类卷吸风险,然后模拟了典型温度分层工况下各取水口下泄水温及上游流速分布。 本文首先通过理论分析及物理模型实验方法研究了不同取水口、泄洪洞开启工况下取水口上游流场水力特征,然后利用ANSYS CFX软件建立了三维(3D)计算水动力学(CFD)数值模型,并利用南京水利科学研究院1：50的物理模型进行验证。该3D CFD模型通过求解雷诺平均纳维-斯托克斯(RANS)方程,结合双方程k-ε模型,研究了多个典型运行工况。理论分析与CFD模拟结果表明白鹤滩水电站取水口上游流场特征在不同运行工况下有显著变化,多取水口与线汇诱导流场在取水口间隔距离2倍之外的上游,速度分布基本一致。本文在利用CFD模型计算流场特征的基础上评估鱼类卷吸风险,结果表明鱼类卷吸风险区域范围与水库水位、取水口流量及运行模式有关,在低水位工况下更大。 温度是下泄水体关键指标之一,控制下泄水温对下游河道的生态环境非常重要。本文根据白鹤滩水库水温的季节性分布,利用3D CFD模拟了白鹤滩水电站取水口及泄洪洞工作工况的下泄水温,并对比分析了多种工况下下泄水温及流场特性,结果表明取水口下泄水温在夏季低水位工况下最高；右岸取水口下泄水温较低；泄洪工况下取水口下泄水温相比于发电工况在不同温度分层时有0.1～1.3℃的升高幅度。
[Abstract]:The induced flow field at the intake point of the hydropower station is of great significance to the risk assessment of fish entrainment in the reservoir area, and the flow field and temperature distribution directly affect the drainage temperature of the reservoir. The Baihetan Hydropower Station is located in the lower reaches of the Jinsha River, and there are 9 water intake outlets on the left and right banks. There are three flood discharge tunnels on the left bank. This paper takes the hydropower station as the research object, sums up the hydrodynamic characteristics and calculates the range of fish entrainment risk area by studying the upstream flow field distribution of the intake outlet under different working conditions. In this paper, the characteristics of hydrodynamic elements in the upper reaches of the left bank are discussed, and the risk of fish entrainment under various simulated conditions is evaluated. Then, the temperature distribution and the upstream velocity distribution are simulated under the typical temperature stratification condition. In this paper, the hydraulic characteristics of the upstream flow field at different intake points and discharge tunnels are studied by means of theoretical analysis and physical model experiments, and then a 3D hydrodynamic CFDs numerical model is established by using ANSYS CFX software. The model is verified by the 1:50 physical model of Nanjing Institute of Water Conservancy Sciences. The 3D CFD model is solved by solving the Reynolds mean Navier-Stokes Stokes (RANS) equation, combined with the two-side K- 蔚 model. Several typical operating conditions are studied. Theoretical analysis and CFD simulation results show that the characteristics of the upstream flow field at the intake point of Baihetan Hydropower Station vary significantly under different operating conditions. The velocity distribution of multi-inlet and line-sink induced flow field is basically the same as that of the upstream flow field which is more than 2 times the distance between the intake points. In this paper, the fish entrainment risk is evaluated on the basis of calculating the characteristics of the flow field by using the CFD model. The results show that the risk range of fish entrainment is related to reservoir water level, intake discharge and operation mode, and is larger under low water level condition. The temperature is one of the key indexes of the drainage water body, and it is very important for the ecological environment of the downstream river channel to control the temperature of the drainage water. According to the seasonal distribution of the water temperature of Baihetan Reservoir, Using 3D CFD to simulate the discharge temperature of water intake and discharge tunnel of Baihetan Hydropower Station, and to compare and analyze the characteristics of discharge temperature and flow field under various working conditions. The results show that the outlet discharge temperature is the highest under low water level in summer. The discharge temperature of the right bank intake outlet is lower than that of the power generation condition, and the temperature of the outlet drain under the flood discharge condition has a rise range of 0.1 ~ 1.3 鈩，

本文编号：1595691