当卡水电站下游局部冲刷模拟研究
发布时间：2024-05-19 18:24
泄水建筑物下游局部冲刷问题是水利水电工程安全稳定运行的关键问题。为了研究泄水建筑物下游冲刷平衡状态下冲刷坑的形状和深度,本文以当卡水电站为研究对象,以模型试验的16组实验数据作为数值模拟的验证依据,基于FLOW-3D对4种网格计算结果进行了敏感性分析,对不同流速和不同中值粒径条件下电站下游冲刷过程进行了三维数值模拟研究,对三种推移质输沙率公式(Meyer-Peter,Nielsen,Vanrijn)计算结果进行了分析比较。论文结论如下:(1)在不同流量条件下,4种网格模拟得到的流量相对误差都较小。在较大流量时,模拟得到的进口平均速度和冲刷深度与实验数据具有良好的一致性;在较小的流量下,模拟结果误差较大。(2)冲刷过程可以分为以下三个阶段。在初始冲刷阶段,流速大,冲刷强度高。在第二冲刷阶段,冲刷坑深度和范围迅速增加。在冲刷第三阶段,冲刷坑的形态改变较小,接近平衡。在开始冲刷的40%时段内,冲刷坑深度可达到冲刷平衡深度的80%。(3)在泥沙中值粒径为50mm、进口流量为345.36 m3/s条件下,模拟得到的冲刷坑深度和长度与实验的相对误差分别为0.87%和1.5%。...
【文章页数】：70 页
【学位级别】：硕士
【文章目录】：
摘要
ABSTRACT
ABBREVIATIONS
CHAPTER1 INTRODUCTION
1.1 Research backgrounds and significances
1.1.1 Research backgrounds
1.1.2 Research significances
1.2 Literature Reviews
1.2.1 Theoretical sediment scouring
1.2.2 Numerical study
1.3 Research Contents and methods
1.3.1 Research contents
1.3.2 Research methods
CHAPTER2 MODEL TEST OBSERVATION RESULTS AND NUMERICAL MODEL
2.1 Overview of Dangka hydropower station
2.2 Model test results
2.3 Numerical modeling
2.3.1 Governing equations and turbulence models
2.3.2 Sediment scour model
2.4 Numerical setup
2.4.1 Numerical simulation condition
2.4.2 Calculation domain
2.4.3 Boundary condition
2.4.4 Meshing
2.4.5 Summery
CHAPTER3 LOCAL SCOUR DOWNSTREAM SIMULATION OF THE RELEASE STRUCTURE
3.1 Mesh sensitive analysis
3.1.1 Flowrate
3.1.2 Velocity distribution at the end of apron
3.2 Flow field information
3.2.1 Velocity field information
3.2.2 Pressure field information
3.3 Bed shear stress
3.4 Sediment scour
3.4.1 The relationship between maximum scour depth and time
3.4.2 The depth and length of scour hole
3.4.3 Development shape of scouring hole
3.4.4 Comparison of sediment transport formulas
3.4.5 Comparison of different sediment sizes
3.4.6 Comparison of different flowrates
3.4.7 Summery
CHAPTER4 CONCLUSIONS AND RECOMMENDATIONS
4.1 Conclusions
4.2 Recommendations
REFERENCES
ACKNOWLEDGEMENTS
AUTHOR BIOGRAPHY
本文编号：3978282
【文章页数】：70 页
【学位级别】：硕士
【文章目录】：
摘要
ABSTRACT
ABBREVIATIONS
CHAPTER1 INTRODUCTION
1.1 Research backgrounds and significances
1.1.1 Research backgrounds
1.1.2 Research significances
1.2 Literature Reviews
1.2.1 Theoretical sediment scouring
1.2.2 Numerical study
1.3 Research Contents and methods
1.3.1 Research contents
1.3.2 Research methods
CHAPTER2 MODEL TEST OBSERVATION RESULTS AND NUMERICAL MODEL
2.1 Overview of Dangka hydropower station
2.2 Model test results
2.3 Numerical modeling
2.3.1 Governing equations and turbulence models
2.3.2 Sediment scour model
2.4 Numerical setup
2.4.1 Numerical simulation condition
2.4.2 Calculation domain
2.4.3 Boundary condition
2.4.4 Meshing
2.4.5 Summery
CHAPTER3 LOCAL SCOUR DOWNSTREAM SIMULATION OF THE RELEASE STRUCTURE
3.1 Mesh sensitive analysis
3.1.1 Flowrate
3.1.2 Velocity distribution at the end of apron
3.2 Flow field information
3.2.1 Velocity field information
3.2.2 Pressure field information
3.3 Bed shear stress
3.4 Sediment scour
3.4.1 The relationship between maximum scour depth and time
3.4.2 The depth and length of scour hole
3.4.3 Development shape of scouring hole
3.4.4 Comparison of sediment transport formulas
3.4.5 Comparison of different sediment sizes
3.4.6 Comparison of different flowrates
3.4.7 Summery
CHAPTER4 CONCLUSIONS AND RECOMMENDATIONS
4.1 Conclusions
4.2 Recommendations
REFERENCES
ACKNOWLEDGEMENTS
AUTHOR BIOGRAPHY
本文编号：3978282
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