设计简介
摘 要
本文的研究是以汽车用液力变矩器为研究对象，基于三维流场理论，借助于UG、GAMBIT、FLUENT等软件，对液力变矩器的内流场进行了仿真计算。本课题研究的目的和意义就在于，通过CFD软件的模拟仿真，对液力变矩器的流道的压力和速度进行有效分析计算。本文主要有以下内容：
(1)首先介绍了课题研究的背景，液力变矩器在国内外的应用情况和流场理论的发展现状，指出了液力变矩器设计计算的发展方向是三维流场理论；然后对液力变矩器的组成以及工作原理进行了阐述，并指出了主要研究内容。
(2)阐述了计算流体力学的基本理论。首先列出了控制方程包括连续性方程和动量守恒方程，由于本课题研究的是不可压缩流体，热交换量可以忽略不计，敌不考虑能量守恒方程，然后介绍了将控制方程离散化的方法；接着详细介绍了有限体积法的基本原理，常用的离散格式：分析了网格的生成技术，分别对结构网格、非结构网格以及混合网格作了阐述；最后介绍了常用的湍流模型，湍流流动的近壁处理方法和流场数值计算的算法。介绍了反求发测绘液力变矩器。
(3)介绍了常用的一些CFD软件，并选择FLUENT对本课题进行研究；为了能够顺利地得到收敛解，提出了研究液力变矩器流场的一些假设，并对流场进行了一定的简化；然后通过CAD软件UG建立叶轮流道的几何模型，并使用GAMBIT生成计算网格，为了提高计算精度，使用六面体网格；选择分离求解器隐式格式进行求解，使用绝对速度方程，湍流模型选择标准k一￡模型，同时使用标准壁面函数；离散格式采用二阶迎风格式(这样可以提高解算精度)，压力一速度耦合选用SIMPLE算法，入口边界条件使用压力入口，出口边界条件使用压力出口，其余壁面使用非滑移壁面边界条件；在叶轮之间的交互面上使用混合平面模型。
(4)对计算结果进行了分析，并与实验结果进行了比较，二者基本吻合证明了三维流场分析的正确性。最后对研究过程中存在的问题进行了分析。
(5)对全文进行了总结。
关键词：液力变矩器、内流场、FLUENT
ABASTRACT
The research is a part of national fund project of key laboratory of the vehicle transmission. The internal flow field of the car model torque converter was numerically simulated by UCH GAMBIT and FLUENT, based on 3-D flow field theory. To do the research in order to solve the problem that hydraulic transmission efficiency and the precision of designs were low and change a situation of long R&D period and low success rate, and further improve the performance of the torque converter and designing and manufacturing level.
The following is the main contents:
(1)Firstly, the background of subject research and the application of the torque converter in the world and the current situation of the development of the field flow theory was introduced, and 3-D field flow theory will be used in design calculation on torque converter in the future; Then composition and operation principle of the converter were explained and the main contents of research was introduced.
(2 )Basic theories of CFD was introduced. The governing equation, including mass conservation equation and momentum conservation equation, was listed. Because the basic of research was the incompressible fluid and the hot could be ignored, so the energy conservation equation was not considered; Then introduced the basic principle of the limited volume method in detail, discrete scheme, the creation technology of the grid and turbulent model and introduced the method of near wall treatment methods and the algorithm of calculating field flows.
(3)carry on simplify Introduced some CFD software and research; For getting result smoothly, to choose FLUENT to were taken; To set up the geometric model by assumptions and FLUENT and to create the grid by GAMBIT. And in order to improve the precision of calculating, to use the grid of hexahedron; To choose separated solver and the implicit scheme model, the turbulent model was the standard k-
:model and the standard wall function was used at the same time; The boundary condition of the entry was the pressure inlet and that of the exit is the pressure outlet and other wall used non- slip wall; Mixing plane model was used in mutual faces between impellers.
(4 ) The results of calculation was analyzed and was compared with those of experiment, and maximum error was less than 5%, which proved that three dimensional calculation was correct. Finally some questions in research was analyzed.
(5)Summary finally.
Key words: the torque converter, internal flow field，FLUENT
目 录
第
第1章 绪 论 1
1．1研究背景 1
1．1．1液力变矩器在国内外的应用 1
1．1．2流场理论的发展现状 2
1．2液力变矩器的组成及工作原理 4
1．2．1液力变矩器的组成 4
1．2．2液力变矩器的工作原理 5
1．3研究目的和意义以及主要研究内容 7
1．3．1研究目的和意义 7
1．3．2主要研究内容 7
第2章 液力变矩器的测绘和反求 8
2. 1测绘过程 8
2. 2三维光学测量仪编程 9
2. 3数据处理和反求 12
第3章 液力变矩器内流场数值分析 14
3．1常用的CFD软件介绍 14
3.2建立流场计算的几何模型 15
3．2. 1分析中的假设和简化 15
3．2．2几何模型 16
3．3生成计算网格 17
3．3．1 GAMBIT简介 17
3. 3．2划分网格 18
3．4设置求解器 19
3．4. 1求解器的选择 19
3．4．2控制方程的线性化 21
3．4．3参考压力的选择 21
3．5选择湍流模型 22
3.6定义流体的物理性质 23
3.7设置边界条件和初始条件 24
3．7．1入口边界条件 24
3．7．2出口边界条件 24
3．7．3壁面边界条件 25
3．7．4初始条件 25
3．8收敛准则 26
3．9本章小结 26
第4章 液力变矩器内流场计算结果分析 27
4．1泵轮流场分析 27
4．1．1泵轮入口流场 29
5．1．2泵轮出口面流场 29
4．2涡轮流场分析 30
4．2．1涡轮入口流场 32
4．2．2涡轮出口流场 32
4. 3导轮流场分析 33
4．3．1导轮入口流场 35
4．3．2导轮出口流场 35
4．4本章小结 36
第5章 全文总结 37
参 考 文 献 39
致 谢 40
本文的研究是以汽车用液力变矩器为研究对象，基于三维流场理论，借助于UG、GAMBIT、FLUENT等软件，对液力变矩器的内流场进行了仿真计算。本课题研究的目的和意义就在于，通过CFD软件的模拟仿真，对液力变矩器的流道的压力和速度进行有效分析计算。本文主要有以下内容：
(1)首先介绍了课题研究的背景，液力变矩器在国内外的应用情况和流场理论的发展现状，指出了液力变矩器设计计算的发展方向是三维流场理论；然后对液力变矩器的组成以及工作原理进行了阐述，并指出了主要研究内容。
(2)阐述了计算流体力学的基本理论。首先列出了控制方程包括连续性方程和动量守恒方程，由于本课题研究的是不可压缩流体，热交换量可以忽略不计，敌不考虑能量守恒方程，然后介绍了将控制方程离散化的方法；接着详细介绍了有限体积法的基本原理，常用的离散格式：分析了网格的生成技术，分别对结构网格、非结构网格以及混合网格作了阐述；最后介绍了常用的湍流模型，湍流流动的近壁处理方法和流场数值计算的算法。介绍了反求发测绘液力变矩器。
(3)介绍了常用的一些CFD软件，并选择FLUENT对本课题进行研究；为了能够顺利地得到收敛解，提出了研究液力变矩器流场的一些假设，并对流场进行了一定的简化；然后通过CAD软件UG建立叶轮流道的几何模型，并使用GAMBIT生成计算网格，为了提高计算精度，使用六面体网格；选择分离求解器隐式格式进行求解，使用绝对速度方程，湍流模型选择标准k一￡模型，同时使用标准壁面函数；离散格式采用二阶迎风格式(这样可以提高解算精度)，压力一速度耦合选用SIMPLE算法，入口边界条件使用压力入口，出口边界条件使用压力出口，其余壁面使用非滑移壁面边界条件；在叶轮之间的交互面上使用混合平面模型。
(4)对计算结果进行了分析，并与实验结果进行了比较，二者基本吻合证明了三维流场分析的正确性。最后对研究过程中存在的问题进行了分析。
(5)对全文进行了总结。
关键词：液力变矩器、内流场、FLUENT
ABASTRACT
The research is a part of national fund project of key laboratory of the vehicle transmission. The internal flow field of the car model torque converter was numerically simulated by UCH GAMBIT and FLUENT, based on 3-D flow field theory. To do the research in order to solve the problem that hydraulic transmission efficiency and the precision of designs were low and change a situation of long R&D period and low success rate, and further improve the performance of the torque converter and designing and manufacturing level.
The following is the main contents:
(1)Firstly, the background of subject research and the application of the torque converter in the world and the current situation of the development of the field flow theory was introduced, and 3-D field flow theory will be used in design calculation on torque converter in the future; Then composition and operation principle of the converter were explained and the main contents of research was introduced.
(2 )Basic theories of CFD was introduced. The governing equation, including mass conservation equation and momentum conservation equation, was listed. Because the basic of research was the incompressible fluid and the hot could be ignored, so the energy conservation equation was not considered; Then introduced the basic principle of the limited volume method in detail, discrete scheme, the creation technology of the grid and turbulent model and introduced the method of near wall treatment methods and the algorithm of calculating field flows.
(3)carry on simplify Introduced some CFD software and research; For getting result smoothly, to choose FLUENT to were taken; To set up the geometric model by assumptions and FLUENT and to create the grid by GAMBIT. And in order to improve the precision of calculating, to use the grid of hexahedron; To choose separated solver and the implicit scheme model, the turbulent model was the standard k-
:model and the standard wall function was used at the same time; The boundary condition of the entry was the pressure inlet and that of the exit is the pressure outlet and other wall used non- slip wall; Mixing plane model was used in mutual faces between impellers.(4 ) The results of calculation was analyzed and was compared with those of experiment, and maximum error was less than 5%, which proved that three dimensional calculation was correct. Finally some questions in research was analyzed.
(5)Summary finally.
Key words: the torque converter, internal flow field，FLUENT
目 录
第
第1章 绪 论 1
1．1研究背景 1
1．1．1液力变矩器在国内外的应用 1
1．1．2流场理论的发展现状 2
1．2液力变矩器的组成及工作原理 4
1．2．1液力变矩器的组成 4
1．2．2液力变矩器的工作原理 5
1．3研究目的和意义以及主要研究内容 7
1．3．1研究目的和意义 7
1．3．2主要研究内容 7
第2章 液力变矩器的测绘和反求 8
2. 1测绘过程 8
2. 2三维光学测量仪编程 9
2. 3数据处理和反求 12
第3章 液力变矩器内流场数值分析 14
3．1常用的CFD软件介绍 14
3.2建立流场计算的几何模型 15
3．2. 1分析中的假设和简化 15
3．2．2几何模型 16
3．3生成计算网格 17
3．3．1 GAMBIT简介 17
3. 3．2划分网格 18
3．4设置求解器 19
3．4. 1求解器的选择 19
3．4．2控制方程的线性化 21
3．4．3参考压力的选择 21
3．5选择湍流模型 22
3.6定义流体的物理性质 23
3.7设置边界条件和初始条件 24
3．7．1入口边界条件 24
3．7．2出口边界条件 24
3．7．3壁面边界条件 25
3．7．4初始条件 25
3．8收敛准则 26
3．9本章小结 26
第4章 液力变矩器内流场计算结果分析 27
4．1泵轮流场分析 27
4．1．1泵轮入口流场 29
5．1．2泵轮出口面流场 29
4．2涡轮流场分析 30
4．2．1涡轮入口流场 32
4．2．2涡轮出口流场 32
4. 3导轮流场分析 33
4．3．1导轮入口流场 35
4．3．2导轮出口流场 35
4．4本章小结 36
第5章 全文总结 37
参 考 文 献 39
致 谢 40
