山区河流上下双丁坝水流特性的数值模拟
发布时间：2018-09-11 13:07
【摘要】：丁坝作为航道整治的建筑物,在实际的山区河流工程中被广泛地使用。丁坝的修建能够起到冲刷航深、减小近岸水流速度保护河岸的作用,但同时也会造成水流的分离和回流,使得丁坝附近水流呈现复杂的三维特性。采用三维水流数学模型对丁坝附近区域流场的变化进行模拟,对航道整治工程的规划和设计具有较重要的参考实用价值。至今为止,关于双丁坝附近区域流场的三维数值模拟计算还比较少。因此,研究双丁坝周围三维水流特性具有十分重要的理论和工程意义。本文以计算流体力学的理论为基础,以四面体非结构网格为单位离散划分三维区域进行建模,借助Fluent软件将水流连续方程、动量方程以及标准的k-ε两方程进行联立求解,采用有限体积法对方程进行离散,并用PISO算法对离散后的方程组进行求解,比较精确的模拟了双丁坝周围的三维水流特性,取得了以下几方面的研究成果:(1)模拟结果表明,使用VOF方法来捕捉双丁坝周围自由水面线,与实际情况比较吻合,模拟效果较好;采用三维湍流模型和k-ε两方程模型在计算三维双丁坝周围紊动能和紊动耗散率时结果比较可靠,该研究方法能够为相应的物理模型实验和理论分析提供一定的理论支撑。(2)通过对VOF方法捕捉到的自由水面进行分析处理,得到双丁坝周围自由水面线在坝前、坝中和坝后沿横向的分布,以及自由水面线在主流区、中间坝头连线所在区域和靠近左岸处沿纵向的分布。(3)借助Tecplot后处理软件对三维模拟计算的流场进行断面剖分,得到不同坝长、水深和坝头型式时的流速在坝前、坝中和坝后沿横向的分布云图,流速在右岸主流区、中间双丁坝坝头连线区域以及靠近左岸时沿纵向的变化以及流速在垂向上的分布。(4)通过Fluent软件的后处理功能,得到紊动能和紊动耗散率在底层,中间层和顶层上沿横向、纵向和垂向上的分布云图和散点分布图,通过分析得到了不同的下丁坝长度、坝间距和水深时的紊动能和紊动耗散率沿横向、纵向和垂向的分布规律以及最大紊动能和紊动耗散率所在的位置。(5)以三维立体图的形式形象地展现双丁坝坝体上的动水压强分布云图,通过对不同工况下的动水压强分布云图进行分析比较,得到了不同的下丁坝长度、挑角和初始水深时的动水压强分布规律以及最大动水压强分布位置。
[Abstract]:As a waterway regulation building, spur-dike is widely used in practical mountain river engineering. The construction of the spur dike can scour the navigation depth and reduce the velocity of the near-shore flow to protect the riverbank, but at the same time, it will also lead to the separation and reflux of the flow, which makes the flow around the dike appear complex three-dimensional characteristics. Three-dimensional flow mathematical model is used to simulate the variation of flow field in the vicinity of spur dike, which has important reference and practical value for the planning and design of waterway regulation project. Up to now, there are few three-dimensional numerical simulations about the flow field near double spur dams. Therefore, it is of great theoretical and engineering significance to study the three-dimensional flow characteristics around double spur dams. In this paper, based on the theory of computational fluid dynamics, the tetrahedron unstructured mesh is used as the unit to divide the three-dimensional region into three dimensional regions. The flow continuity equation, momentum equation and standard k- 蔚 equation are solved simultaneously by Fluent software. The finite volume method is used to discretize the equations and the PISO algorithm is used to solve the discrete equations. The three-dimensional flow characteristics around the double spur dams are simulated accurately. The following research results are obtained: (1) the simulation results show that, The VOF method is used to capture the free water surface line around the double spur dam, which is in good agreement with the actual situation, and the simulation effect is good. Three dimensional turbulence model and k- 蔚 equation model are used to calculate the turbulent energy and turbulent dissipation rate around the double spur dam. The research method can provide some theoretical support for the corresponding physical model experiments and theoretical analysis. (2) through the analysis and treatment of the free water surface captured by VOF method, the free water surface line around the double spur dam is obtained in front of the dam. The transverse distribution of the dam after the dam and the distribution of the free water surface line in the mainstream area, the middle dam head line and the longitudinal distribution near the left bank. (3) the three-dimensional simulated flow field is dissected with the help of Tecplot post-processing software. The distribution of velocity in front of the dam, along the lateral direction of the dam and at the back of the dam is obtained with different dam length, water depth and dam head type, and the velocity of velocity is in the mainstream area of the right bank. The longitudinal variation and vertical distribution of velocity in the connecting region of the middle double spur dam head and near the left bank. (4) through the post processing function of Fluent software, the turbulent energy and the turbulent dissipation rate are obtained in the bottom layer, the middle layer and the top layer along the transverse direction. The vertical and vertical distribution cloud maps and scattered point distributions are obtained by analyzing the length of the lower groin, the turbulent energy and the turbulent dissipation rate along the transverse direction of the dike, the spacing of the dike and the depth of the water. The distribution law of longitudinal and vertical direction and the location of the maximum turbulent energy and turbulent dissipation rate. (5) the distribution of hydrodynamic pressure on the double spur dam body is vividly shown in the form of three-dimensional stereogram. Through the analysis and comparison of the distribution of hydrodynamic pressure in different working conditions, the distribution of hydrodynamic pressure and the distribution of maximum hydrodynamic pressure are obtained for different dike length, angle and initial water depth.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U617.91
本文编号：2236767
[Abstract]:As a waterway regulation building, spur-dike is widely used in practical mountain river engineering. The construction of the spur dike can scour the navigation depth and reduce the velocity of the near-shore flow to protect the riverbank, but at the same time, it will also lead to the separation and reflux of the flow, which makes the flow around the dike appear complex three-dimensional characteristics. Three-dimensional flow mathematical model is used to simulate the variation of flow field in the vicinity of spur dike, which has important reference and practical value for the planning and design of waterway regulation project. Up to now, there are few three-dimensional numerical simulations about the flow field near double spur dams. Therefore, it is of great theoretical and engineering significance to study the three-dimensional flow characteristics around double spur dams. In this paper, based on the theory of computational fluid dynamics, the tetrahedron unstructured mesh is used as the unit to divide the three-dimensional region into three dimensional regions. The flow continuity equation, momentum equation and standard k- 蔚 equation are solved simultaneously by Fluent software. The finite volume method is used to discretize the equations and the PISO algorithm is used to solve the discrete equations. The three-dimensional flow characteristics around the double spur dams are simulated accurately. The following research results are obtained: (1) the simulation results show that, The VOF method is used to capture the free water surface line around the double spur dam, which is in good agreement with the actual situation, and the simulation effect is good. Three dimensional turbulence model and k- 蔚 equation model are used to calculate the turbulent energy and turbulent dissipation rate around the double spur dam. The research method can provide some theoretical support for the corresponding physical model experiments and theoretical analysis. (2) through the analysis and treatment of the free water surface captured by VOF method, the free water surface line around the double spur dam is obtained in front of the dam. The transverse distribution of the dam after the dam and the distribution of the free water surface line in the mainstream area, the middle dam head line and the longitudinal distribution near the left bank. (3) the three-dimensional simulated flow field is dissected with the help of Tecplot post-processing software. The distribution of velocity in front of the dam, along the lateral direction of the dam and at the back of the dam is obtained with different dam length, water depth and dam head type, and the velocity of velocity is in the mainstream area of the right bank. The longitudinal variation and vertical distribution of velocity in the connecting region of the middle double spur dam head and near the left bank. (4) through the post processing function of Fluent software, the turbulent energy and the turbulent dissipation rate are obtained in the bottom layer, the middle layer and the top layer along the transverse direction. The vertical and vertical distribution cloud maps and scattered point distributions are obtained by analyzing the length of the lower groin, the turbulent energy and the turbulent dissipation rate along the transverse direction of the dike, the spacing of the dike and the depth of the water. The distribution law of longitudinal and vertical direction and the location of the maximum turbulent energy and turbulent dissipation rate. (5) the distribution of hydrodynamic pressure on the double spur dam body is vividly shown in the form of three-dimensional stereogram. Through the analysis and comparison of the distribution of hydrodynamic pressure in different working conditions, the distribution of hydrodynamic pressure and the distribution of maximum hydrodynamic pressure are obtained for different dike length, angle and initial water depth.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U617.91
【参考文献】
相关期刊论文 前10条
1 刘易庄;蒋昌波;邓斌;王刚;;淹没双丁坝间水流结构特性PIV试验[J];水利水电科技进展;2015年06期
2 李明龙;王平义;刘怀汉;喻涛;;山区河流双丁坝水面线试验研究[J];中国水运(下半月);2014年11期
3 魏文礼;蔡亚希;;淹没丁坝三维水流数值模拟研究[J];水资源与水工程学报;2014年03期
4 李冰冻;李嘉;李克锋;;丁坝水流的水槽试验及数值模拟研究[J];水动力学研究与进展A辑;2013年02期
5 张可;王平义;喻涛;;不同坝型丁坝坝体周围水流紊动特性试验研究[J];水运工程;2012年07期
6 周银军;刘焕芳;何春光;宗全利;;桩柱透水丁坝水流特性试验研究[J];泥沙研究;2009年05期
7 陈稚聪;黑鹏飞;丁翔;;丁坝回流区水流紊动强度试验[J];清华大学学报(自然科学版);2008年12期
8 张华庆;曹艳敏;王建军;;丁坝紊动特性试验研究[J];水道港口;2008年03期
9 沙海飞;周辉;吴时强;陈惠玲;;坝身泄洪水气两相流二维数值模拟[J];水动力学研究与进展A辑;2007年03期
10 凌建明;官盛飞;赵鸿铎;林小平;赵志华;;绕流丁坝附近流场数值分析[J];公路交通科技;2006年11期
相关会议论文 前1条
1 胡子俊;叶洲腾;赵西增;孙志林;;基于FLUENT的三维丁坝绕流数值模拟[A];第十三届全国水动力学学术会议暨第二十六届全国水动力学研讨会文集——G海岸环境与地球物理流体力学[C];2014年
相关博士学位论文 前2条
1 黑鹏飞;丁坝回流区水流特性的实验研究[D];清华大学;2009年
2 李洪;丁坝水力学特性研究[D];四川大学;2003年
相关硕士学位论文 前5条
1 胡田;双丁坝水流特性的水槽试验和数值模拟研究[D];上海海洋大学;2015年
2 李子龙;明渠流条件下丁坝水流特性研究[D];上海交通大学;2015年
3 吴立春;大坝出闸段水流计算机模拟的应用研究[D];重庆大学;2008年
4 冯丽华;明渠弯道三维水流数值模拟研究[D];扬州大学;2007年
5 李冰冻;航道整治河段流动特性的三维数值模拟[D];四川大学;2003年
，本文编号：2236767
本文链接：https://www.wllwen.com/kejilunwen/shuiwenshuili/2236767.html
