泄洪洞高速水流水力学特性数值模拟研究

发布时间：2021-01-24 09:30

　　锦屏一级大坝是中国最大的水电站项目之一。由于高水头和大泄流量,有发生空蚀破坏的风险。本文使用CFD数值模拟研究,泄洪洞采用掺气坎进行掺气减蚀时,水流的水力特性。论文的主要研究内容和成果如下:1.建立泄洪洞和掺气坎整体模型,为数值模拟计算做准备,以评估气蚀破坏发生的可能性。掺气坎作为预防气蚀破坏的一种措施,是最便宜和最有效的解决方案。泄洪洞中设置有4处掺气坎,全部采用挑坎+跌坎组合型掺气坎,与锦屏实际工程中采用的掺气坎类型一致。2.数值模拟使用FLUENT求解平均Reynolds-averages Navier–Stokes方程。湍流模型选择可实现的k-ε模型,以及应用VOF法计算水气两相流和水气交界面的追踪。针对3种库水位和2种闸门开度,共6种情况,分别为:1880m,1865m和1850m的库水位,以及闸门全开和闸门半开,进行了非稳态数值计算。获得了6种情况下水流的自由面、速度、压强和掺气长度等的数值模拟数据。3.数值模拟的数据与1:30模型实验的数据进行对比验证。在库水位1880m和闸门全开时,4个坎前平均速度的平均误差为3.1%、33个底板压强测点的平均误差为6.16%、31个自... 

【文章来源】：华北电力大学(北京)北京市 211工程院校 教育部直属院校

【文章页数】：79 页

【学位级别】：硕士

【文章目录】：
摘要
Abstract
Acknowledgement
Nomenclature
Chapter 1. Introduction
    1.1. General Description
    1.2. Research Objectives
    1.3. Methodology
    1.4. Thesis Outline
Chapter 2. Theoretical Background
    2.1. Cavitation and its Mechanism
    2.2. Cavitation Parameters
    2.3. Prevention of Cavitation Damage
        2.3.1. Cavitation Prevention
        2.3.2. Controlled Cavity Collapse
        2.3.3. Use of Cavitation-Resistant Materials
        2.3.4. Aeration
    2.4. Concept of Aeration
        2.4.1. Aeration Methods and Mechanisms
        2.4.2. Aerator Location and Spacing
        2.4.3. Estimation of Air Entrainment Capacity
    2.5. Computational Fluid Dynamics
        2.5.1. Governing Equations for CFD
        2.5.2. Pre-Processing
        2.5.3. Solver
    2.6. VOF Model
        2.6.1. The Implicit Scheme
        2.6.2. Limitations
Chapter 3. Various Methods and Stages Used in CFD Modelling of Jinping-I Hydro Project
    3.1. Pre-Processing Stage
    3.2. Solver Stage
    3.3. Post-Processing Stage
        3.3.1. Static Pressure Distribution
        3.3.2. Velocity
        3.3.3. Water surface
Chapter 4. Simulation Results of CFD Modelling of Jinping-I Hydro Project and its Discussion
    4.1. Simulation Results of CFD Modelling of Jinping-I Hydro Project
        4.1.1. Calculation of Velocity and Cavitation Number for Full and Half Conditions at Different WaterLevels
        4.1.2. Calculation of Water Surface Profile for Full and Half Conditions at Different Water Levels
        4.1.3. Calculation of Pressure Distribution for Full and Half Conditions at Different Water Levels
        4.1.4. Calculation of Aeration Cavity Length for Full and Half Conditions at Different Water Levels
    4.2. Discussion and Accuracy Regarding Verification, Convergence and Uncertainty
        4.2.1. Verification of the Model
        4.2.2. Convergence
        4.2.3. Uncertainty and Error in CFD simulations
    4.3. Summary
Chapter 5. Conclusions and Future Works
    5.1. Conclusions
    5.2. Future works
References


【参考文献】：
期刊论文
[1]HYDRAULIC CHARACTERISTICS OF PLUG ENERGY DISSIPATER IN FLOOD DISCHARGE TUNNEL[J]. TIAN Zhong , XU Wei-Lin, WANG Wei, LIU Shan-Jun State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China,.  Journal of Hydrodynamics. 2009(06)
[2]通气减蚀挑坎水力学问题的试验研究[J]. 时启燧,潘水波,邵媖媖,袁小勇.  水利学报. 1983(03)



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