Professors Wen and Huang present current developments in tribology
research along with tribology fundamentals and applications,
including lubrication theory, lubrication design, friction
mechanism, wear mechanism, friction control, and their
applications. In addition to classical tribology, Wen and Huang
cover the research areas of the modern tribology, as well as the
regularities and characteristics of tribological phenomena in
practice. Furthermore, the authors present the basic theory,
numerical analysis methods, and experimental measuring techniques
of tribology as well as their applications in engineering.

* Provides a systematic presentation of tribology fundamentals
and their applications

* Discusses the current states and development trends in
tribology research

* Applies the applications to modern day engineering

* Computer programs available for download from the book's
companion site

Principles of Tribology is aimed at postgraduates and
senior-level undergraduates studying tribology, and can be used for
courses covering theory and applications. Tribology professionals
and students specializing in allied areas of mechanical engineering
and materials science will also find the book to be a helpful
reference or introduction to the topic.

Companion website for the book:
www.wiley.com/go/wen/tribology

Prof. Wen Shizhu, Tsinghua University, China
Wen Shizhu is a Professor at Tsinghua University and a CAS Academician. His research fields cover lubrication theory, nano-tribology and the mechanism and control of friction and wear. In 1956, he participated in drafting 12th "National Scientific Development Plan," and finished the first development planning of friction, wear and lubrication engineering. In the late 80s, he was involved in drafting the "Tribology Field Plan and Development Strategy Report" for the National Science and Technology Committee, the Education Committee, and the National Natural Science Foundation Committee.

Prof. Huang Ping, South China University of Technology, China
Huang Ping is a Professor at South China University of Technology. He obtained his PhD degree from Department of Engineering Mechanics, Tsinghua University, and has worked in the State Key Laboratory of Tribology at Tsinghua University for eight years. He is the head of Institute of mechanical design and equipment, and the State Experimental Training Center of Basic Mechanics of South China University of Technology.

• Provides a systematic presentation of tribology fundamentals and their applications
• Discusses the current states and development trends in tribology research
• Applies the applications to modern day engineering
• Computer programs available for download from the book's companion site

Principles of Tribology is aimed at postgraduates and senior-level undergraduates studying tribology, and can be used for courses covering theory and applications. Tribology professionals and students specializing in allied areas of mechanical engineering and materials science will also find the book to be a helpful reference or introduction to the topic.

Companion website for the book: www.wiley.com/go/wen/tribology

Preface xvii

Introduction xix

PART I LUBRICATION THEORY 1

1 Properties of Lubricants 3

1.1 Lubrication States 3

1.2 Density of Lubricant 6

1.3 Viscosity of Lubricant 7

1.3.1 Dynamic Viscosity and Kinematic Viscosity 7

1.3.2 Relationship between Viscosity and Temperature 9

1.3.3 Relationship between Viscosity and Pressure 11

1.3.4 Relationships between Viscosity, Temperature and Pressure 12

1.4 Non-Newtonian Behaviors 12

1.4.1 Ree-Eyring Constitutive Equation 13

1.4.2 Visco-Plastic Constitutive Equation 13

1.4.3 Circular Constitutive Equation 14

1.4.4 Temperature-Dependent Constitutive Equation 14

1.4.5 Visco-Elastic Constitutive Equation 14

1.4.6 Nonlinear Visco-Elastic Constitutive Equation 15

1.4.7 A Simple Visco-Elastic Constitutive Equation 16

1.5 Wettability of Lubricants 17

1.5.1 Wetting and Contact Angle 17

1.5.2 Surface Tension 18

1.6 Measurement and Conversion of Viscosity 19

1.6.1 Rotary Viscometer 19

1.6.2 Off-Body Viscometer 20

1.6.3 Capillary Viscometer 20

References 22

2 Basic Theories of Hydrodynamic Lubrication 23

2.1 Reynolds Equation 24

2.1.1 Basic Assumptions 24

2.1.2 Derivation of Reynolds Equation 24

2.2 Hydrodynamic Lubrication 27

2.2.1 Mechanism of Hydrodynamic Lubrication 27

2.2.2 Boundary Conditions and Initial Conditions of Reynolds Equation 28

2.2.3 Calculation of Hydrodynamic Lubrication 29

2.3 Elastic Contact Problems 30

2.3.1 Line Contact 30

2.3.2 Point Contact 33

2.4 Entrance Analysis of EHL 36

2.4.1 Elastic Deformation of Line Contacts 36

2.4.2 Reynolds Equation Considering the Effect of Pressure-Viscocity 37

2.4.3 Discussion 37

2.4.4 Grubin Film Thickness Formula 39

2.5 Grease Lubrication 40

References 42

3 Numerical Methods of Lubrication Calculation 43

3.1 Numerical Methods of Lubrication 44

3.1.1 Finite Difference Method 44

3.1.2 Finite Element Method and Boundary Element Method 50

3.1.3 Numerical Techniques 53

3.2 Numerical Solution of the Energy Equation 57

3.2.1 Conduction and Convection of Heat 57

3.2.2 Energy Equation 59

3.2.3 Numerical Solution of Energy Equation 61

3.3 The Numerical Solution of Elastohydrodynamic Lubrication 62

3.3.1 EHL Numerical Solution of Line Contacts 62

3.3.2 EHL Numerical Solution of Point Contacts 67

3.4 Multi-Grid Method for Solving EHL Problems 70

3.4.1 Basic Principles of Multi-Grid Method 70

3.4.2 Nonlinear Full Approximation Scheme of Multi-Grid Method 72

3.4.3 V and W Iterations 74

3.4.4 Multi-Grid Solution of EHL Problems 74

3.4.5 Multi-Grid Integration Method 76

References 79

4 Lubrication Design of Typical Mechanical Elements 81

4.1 Slider and Thrust Bearing 81

4.1.1 Basic Equations 81

4.1.2 Solutions of Slider Lubrication 82

4.2 Journal Bearing 85

4.2.1 Axis Position and Clearance Shape 85

4.2.2 Infinitely Narrow Bearing 86

4.2.3 Infinitely Wide Bearing 88

4.3 Hydrostatic Bearing 92

4.3.1 Hydrostatic Thrust Plate 93

4.3.2 Hydrostatic Journal Bearings 94

4.3.3 Bearing Stiffness and Throttle 94

4.4 Squeeze Bearing 96

4.4.1 Rectangular Plate Squeeze 97

4.4.2 Disc Squeeze 98

4.4.3 Journal Bearing Squeeze 99

4.5 Dynamic Bearing 100

4.5.1 Reynolds Equation of Dynamic Journal Bearings 101

4.5.2 Simple Dynamic Bearing Calculation 103

4.5.3 General Dynamic Bearings 104

4.6 Gas Lubrication Bearings 107

4.6.1 Basic Equations of Gas Lubrication 107

4.6.2 Types of…