《统一坐标系下的计算流体力学 英文版》PDF下载

  • 购买积分:9 如何计算积分?
  • 作  者:许为厚,徐昆著
  • 出 版 社:北京:科学出版社
  • 出版年份:2011
  • ISBN:9787030323194
  • 页数:190 页
图书介绍:计算流体力学是运用大规模数值计算来解决流体的运动问题。众所周知,在流体计算中,一个给定流场的数值解是该流场的流动状态在为其设定的坐标中的体现。计算流体力学通常使用的两个坐标系,即欧拉坐标系和拉格朗日坐标系,既有优点又有不足。欧拉方法相对简单,但是其不足在于:(a)对接触间断的分辨率不足;(b)在流体计算之前先要生成贴体坐标。相反地,拉格朗日方法很好地分辨出接触间断(包括物质介面和自由面),但它的缺点在于:(a)气体动力方程不能写成守恒型偏微分方程的形式,使得数值计算复杂和缺乏唯一性;(b)由于网格扭曲导致计算中断。因此,计算流体力学的基本问题除了深刻理解物理流动之外,同时也要寻找“最优的”坐标系。统一坐标系方法是本书第一作者许为厚教授在前人坐标变换的基础上的进一步发展,并在与其同事多年的合作中建立起来的。在计算流体力学的研究中寻找“最优的”坐标系肯定还会继续下去,目前为止,统一坐标系可较好地结合前两种坐标系的优点,避免它们的不足。例如,统一坐标系可以通过计算自动生成网格,而且网格速度也可以考虑加入避免网格大变形的“扩散”速度。本书首先回顾了一维和多维计算流体力学中的欧拉、拉格朗日以及A

Chapter 1 Introduction 1

1.1 CFD as Numerical Solution to Nonlinear Hyperbolic PDEs 1

1.2 Role of Coordinates in CFD 2

1.3 Outline of the Book 5

References 6

Chapter 2 Derivation of Conservation Law Equations 9

2.1 Fluid as a Continuum 9

2.2 Derivation of Conservation Law Equations in Fixed Coordinates 10

2.3 Conservation Law Equations in Moving Coordinates 14

2.4 Integral Equations versus Partial Differential Equations 14

2.5 The Entropy Condition for Inviscid Flow Computation 17

References 18

Chapter 3 Review of Eulerian Computation for 1-D Inviscid Flow 19

3.1 Flow Discontinuities and Rankine-Hugoniot Conditions 19

3.2 Classification of Flow Discontinuities 21

3.3 Riemann Problem and its Solution 26

3.4 Preliminary Considerations of Numerical Computation 34

3.5 Godunov Scheme 35

3.6 High Resolution Schemes and Limiters 38

3.7 Defects of Eulerian Computation 39

References 40

Chapter 4 1-D Flow Computation Using the Unified Coordinates 43

4.1 Gas Dynamics Equations Based on the Unified Coordinates 43

4.2 Shock-Adaptive Godunov Scheme 45

4.3 The Use of Entropy Conservation Law for Smooth Flow Computation 47

4.4 The Unified Computer Code 48

4.5 Cure of Defects of Eulerian and Lagrangian Computation by the UC Method 52

4.6 Conclusions 66

References 66

Chapter 5 Comments on Current Methods for Multi-Dimensional Flow Computation 69

5.1 Eulerian Computation 69

5.2 Lagrangian Computation 71

5.3 The ALE Computation 73

5.4 Moving Mesh Methods 73

5.5 Optimal Coordinates 74

References 75

Chapter 6 The Unified Coordinates Formulation of CFD 79

6.1 Hui Transformation 79

6.2 Geometric Conservation Laws 80

6.3 Derivation of Governing Equations in Conservation Form 80

References 85

Chapter 7 Properties of the Unified Coordinates 87

7.1 Relation to Eulerian Computation 87

7.2 Relation to Classical Lagrangian Coordinates 87

7.3 Relation to Arbitrary-Lagrangian-Eulerian Computation 88

7.4 Contact Resolution 89

7.5 Mesh Orthogonality 89

7.6 Unified Coordinates for Steady Flow 91

7.7 Effects of Mesh Movement on the Flow 92

7.8 Relation to Other Moving Mesh Methods 92

7.9 Relation to Mesh Generation and the Level-Set Function Method 94

References 94

Chapter 8 Lagrangian Gas Dynamics 97

8.1 Lagrangian Gas Dynamics Equations 97

8.2 Weak Hyperbolicity 98

8.3 Non-Equivalency of Lagrangian and Eularian Formulation 99

References 100

Chapter 9 Steady 2-D and 3-D Supersonic Flow 101

9.1 The Unified Coordinates for Steady Flow 101

9.2 Euler Equations in the Unified Coordinates 102

9.3 The Space-Marching Computation 104

9.4 Examples 105

9.5 3-D Flow 111

References 114

Chapter 10 Unsteady 2-D and 3-D Flow Computation 117

10.1 Summary of Solution to the 2-D Euler Equations Using the Unified Coordinates 117

10.2 Computation Procedure 119

10.3 Examples 122

References 125

Chapter 11 Viscous Flow Computation Using Navier-Stokes Equations 127

11.1 Navier-Stokes Equations in the Unified Coordinates 127

11.2 The Angle-preserving Equation 130

11.3 Advantages of the g-equation Over the h-equation 131

11.4 Boundary Condition and Movement of Boundary Cells 133

11.5 Solution Strategies 134

11.6 Test Examples:Shock/Boundary Flow Interaction and Shock/Shock Interaction 138

References 145

Chapter 12 Applications of the Unified Coordinates to Kinetic Theory 147

12.1 Brief Introduction of Gas-Kinetic Theory 147

12.2 Gas-Kinetic BGK Model Under the Unified Coordinate Transformation 152

12.3 Numerical BGK-NS Scheme in a Moving Mesh System 153

12.4 Numerical Procedure 157

12.5 Numerical Examples 158

12.6 Conclusion 168

References 168

Chapter 13 Summary 171

Appendix A Riemann Problem for 1-D Flow in the Unified Coordinate 173

Appendix B Computer Code for 1-D Flow in the Unified Coordinate 177