Preface Ministry of Education of China issued documents in 2001 to promote bilingual teaching in universities. In recent years, bilingual education has gradually become a hot spot of reform in higher education. Many universities have participated in the bilingual education practice Thermodynamics is a discipline which governs the energy conversion and studies properties of substances as work mediums. "Engineering Thermodynamics"is involved in engineering fields, such as Power Engineering and Machinery, Aerospace, Marine Engineering, chemical engineering, Building Environment and Equipment Engineering and Refrigeration Engineering, etc. It is a fundamental course for these disciplines. And it involves basic theories and theirs applications which are very useful in research fields of the hot topics of many scholars and scientific and technical personnel at domestic and abroad. It is proper for carrying out bilingual teaching of Engineering Thermodynamics. And there are many original English teaching materials to refer. In addition bilingual teaching of Engineering Thermodynamics can help students overcome the language barrier and is very good for them to learn knowledge related to this discipline in English directly in the future. It may help to cultivate the udents' ability to participate in international exchanges. It may get better effect than teaching in Chinese. Many universities have participated in exploration and practice of bilingual education programs. Xi'an University of Architecture and Technology, in which the author works, also have had several biling aching trials on this course toward undergraduates majored in Building Environment and Equipment Engineering since 2004. During the practice in the past five years, we not only used the textbook in Chinese version recommended by the Professional Steering Committee as teaching materials, but also selected the textbook "Thermodynamics(An Engineering approach) edited by Yunus A. Cengel and Michael A. Boles, 2002 copy of the fourth edition by Tsinghua University Press, as English teaching materials. This book is an excellent and well known textbook for Thermodynamics. It not only introduces the basic concepts and principles of thermodynamics and other basic knowledge, but also gives a large number of application examples and relevant content. It is informative and contemporary. It riches in charts and figures and expressed logically with pure, lively English. However, there exist significant deviations, especially the structure of the course, between the original English teaching system and Chinese teaching system of Engineering Thermodynamics". And the textbook in English version is too difficult for most of our students to read This may create great study pressure on the majority of students and have bad influence on students enthusiasm of learning a course in English directly. Thus, it is difficult to achieve a desirable teaching effect of bilingual education without a suitable textbook for them to refer Therefore, with 5 years teaching experience, we organized a group of teaching staffs and compiled this bilingual teaching material. After referring to several original English teaching materials and using bilingual teaching resources of Engineering Thermodynamics on the Internet the layout of the chapters is determined, meeting the domestic requirement on the Syllabus for "Engineering Thermodynamics"of Building Environment and Equipment Engineering major undergraduates education as well. This bilingual textbook is compiled in Chinese and English. It has systematic and integrity. And, the related knowledge and technology of using renewable energy are also briefly introduced in Chapter 12 to broaden the knowledge of student and to help them form sustainable approach to energy use. Several think problems and exercises are given in each chapter written Chinese for reference of different professions and different students at different levels This book is edited by a group of staffs in Xi an University of Architecture and Technology, Zhao
1 Preface Ministry of Education of China issued documents in 2001 to promote bilingual teaching in universities. In recent years, bilingual education has gradually become a hot spot of reform in higher education. Many universities have participated in the bilingual education practice. Thermodynamics is a discipline which governs the energy conversion and studies properties of substances as work mediums. "Engineering Thermodynamics" is involved in engineering fields, such as Power Engineering and Machinery, Aerospace, Marine Engineering, chemical engineering, Building Environment and Equipment Engineering and Refrigeration Engineering, etc. It is a fundamental course for these disciplines. And it involves basic theories and theirs applications which are very useful in research fields of the hot topics of many scholars and scientific and technical personnel at domestic and abroad. It is proper for carrying out bilingual teaching of Engineering Thermodynamics. And there are many original English teaching materials to refer. In addition, bilingual teaching of Engineering Thermodynamics can help students overcome the language barrier and is very good for them to learn knowledge related to this discipline in English directly in the future. It may help to cultivate the students’ ability to participate in international exchanges. It may get better effect than teaching in Chinese. Many universities have participated in exploration and practice of bilingual education programs. Xi'an University of Architecture and Technology, in which the author works, also have had several bilingual teaching trials on this course toward undergraduates majored in Building Environment and Equipment Engineering since 2004. During the practice in the past five years, we not only used the textbook in Chinese version recommended by the Professional Steering Committee as teaching materials, but also selected the textbook "Thermodynamics (An Engineering approach)", edited by Yunus A. Cengel and Michael A. Boles, 2002 copy of the fourth edition by Tsinghua University Press, as English teaching materials. This book is an excellent and well known textbook for Thermodynamics. It not only introduces the basic concepts and principles of thermodynamics and other basic knowledge, but also gives a large number of application examples and relevant content. It is informative and contemporary. It riches in charts and figures and expressed logically with pure, lively English. However, there exist significant deviations, especially the structure of the course, between the original English teaching system and Chinese teaching system of "Engineering Thermodynamics". And the textbook in English version is too difficult for most of our students to read. This may create great study pressure on the majority of students and have bad influence on students’ enthusiasm of learning a course in English directly. Thus, it is difficult to achieve a desirable teaching effect of bilingual education without a suitable textbook for them to refer. Therefore, with 5 years teaching experience, we organized a group of teaching staffs and compiled this bilingual teaching material. After referring to several original English teaching materials and using bilingual teaching resources of Engineering Thermodynamics on the Internet, the layout of the chapters is determined, meeting the domestic requirement on the Syllabus for "Engineering Thermodynamics" of Building Environment and Equipment Engineering major undergraduates’ education as well. This bilingual textbook is compiled in Chinese and English. It has systematic and integrity. And, the related knowledge and technology of using renewable energy are also briefly introduced in Chapter 12 to broaden the knowledge of student and to help them form sustainable approach to energy use. Several think problems and exercises are given in each chapter written in Chinese for reference of different professions and different students at different levels. This book is edited by a group of staffs in Xi’an University of Architecture and Technology, Zhao
Lei is the chief compiler. The preface, Chapter 2, 4 and 5 are compiled by the Zhao Lei; Chapters 6, 7, 8 and 10 in English are jointly accomplished by Zhao Lei and Zhu Chang-lin; Chapter 9 in English is accomplished by Zhao Lei and Guo Ya-jun; Chapter 1 and 3 bilingually and Chapter 9 in Chinese are compiled by Guo Ya-jun; Chapters 6, 7, 8 bilingually and Chapter 10 in Chinese is compiled by Zhu Chang-lin; Chapter ll is compiled by Liu Yun-xia; Chapter 12 is compiled by the Cui Hai-hang Herewith, let us express our heartfelt thanks to Professor Liu Xian-ding of Xi'an University of rchitecture and Technology for his careful review on the manuscript. We greatly appreciate the valuable comments and revision suggestions he gave us. These are helpful for the improvement in the quality of the manuscript In addition we are also very grateful for the contribution of several graduate students, especially Liu Lei, in Xi'an University of Architecture and Technology in drawing the Figures used in this textbook Editor's academic standards and the limited teaching experience, the book will inevitably be some mistakes and wrong, and sincerely hope that readers and students to use the book valuable comments and suggestions
2 Lei is the chief compiler. The preface, Chapter 2,4 and 5 are compiled by the Zhao Lei; Chapters 6,7,8 and 10 in English are jointly accomplished by Zhao Lei and Zhu Chang-lin; Chapter 9 in English is accomplished by Zhao Lei and Guo Ya-jun; Chapter 1 and 3 bilingually and Chapter 9 in Chinese are compiled by Guo Ya-jun; Chapters 6,7,8 bilingually and Chapter 10 in Chinese is compiled by Zhu Chang-lin; Chapter 11 is compiled by Liu Yun-xia; Chapter 12 is compiled by the Cui Hai-hang. Herewith, let us express our heartfelt thanks to Professor Liu Xian-ding of Xi'an University of Architecture and Technology for his careful review on the manuscript. We greatly appreciate the valuable comments and revision suggestions he gave us. These are helpful for the improvement in the quality of the manuscript. In addition, we are also very grateful for the contribution of several graduate students, especially Liu Lei, in Xi’an University of Architecture and Technology in drawing the Figures used in this textbook. Editor's academic standards and the limited teaching experience, the book will inevitably be some mistakes and wrong, and sincerely hope that readers and students to use the book valuable comments and suggestions
Table of contents Introduction 0. 1 Energy Resources and Utilization of Thermal Energy 0.2 The Studies and Main Contents of Engineering Thermodynamics 0.3 Engineering Thermodynamics Approaches Chapter 1 Basic Concepts 1.1 Thermodynamic System 3333 1.1.2 Categories of Systems 1.2 Thermodynamic States and Basic Properties 1. 2. 1 States and States Properties 1. 2. 2 Basic State Properti 1.3 Equilibrium State, State Equation and State Diagram 1.3. 1 Equilibrium State 1.3.2 The State Postulate 1.3.3 Equation of State 1.4 Quasi-equilibrium Process and Reversible Process 1. 4.1 Quasi-equilibrium Process 14.2 Reversible process 1.5 A Thermodynamic cycle 1.5. 1 Power Cycle 1.5.2 The Refrigeration Cycle Chapter 2 The First Law of Thermodynamic 2. 1 Total Energy of a System 24 2. 1. 1 Thermodynamic(Internal)Energy 2. 1. 2 Potential and Kinetic Energy 2.1.3 Total Energy and Energy Change of a System 2.2 Energy Transfer by Heat, Work or Mass 2.2. 1 Energy Transfer by Heat and by work 2.2.2 Total Energy of a Flowing Fluid and enthalpy 2. 3 Energy Balance for Closed Systems 2.3. 1 Energy Balance of a Closed System 2.3.2 Corollaries of the First 2. 4 Energy Balance for Open Systems 34 2. 4. 1 Mass Balance for Open Systems 2. 4.2 Energy Balance for Open Systems. 2. 4.3 Energy Balance for Steady-Flow Processes 2-5 Some Steady-Flow Devices in Engineering Practice 2.5. 1 Turbines and Compressors 2.5.2 Heat Exchangers 2.5.3 NoZZles and Diffusers 2.5.3 Throttling Devices
3 Table of Contents Introduction ..........................................................................................................................10 0.1 Energy Resources and Utilization of Thermal Energy......................................................10 0.2 The Studies and Main Contents of Engineering Thermodynamics.....................................12 0.3 Engineering Thermodynamics Approaches ....................................................................13 Chapter 1 Basic Concepts....................................................................................................13 1.1 Thermodynamic System ..........................................................................................13 1.1.1 Thermodynamic System ....................................................................................13 1.1.2 Categories of Systems.......................................................................................14 1.1.3 Working Fluid..................................................................................................15 1.2 Thermodynamic States and Basic Properties ..........................................................15 1.2.1 States and States Properties................................................................................15 1.2.2 Basic State Properties........................................................................................16 1.3 Equilibrium State, State Equation and State Diagram ..............................................19 1.3.1 Equilibrium State..............................................................................................19 1.3.2 The State Postulate............................................................................................19 1.3.3 Equation of State ..............................................................................................20 1.4 Quasi-equilibrium Process and Reversible Process.................................................20 1.4.1 Quasi-equilibrium Process .................................................................................20 1.4.2 Reversible Process............................................................................................21 1.5 A Thermodynamic Cycle..........................................................................................22 1.5.1 Power Cycle.....................................................................................................22 1.5.2 The Refrigeration Cycle.....................................................................................23 Chapter 2 The First Law of Thermodynamics .......................................................................24 2.1 Total Energy of a System ........................................................................................24 2.1.1 Thermodynamic (Internal) Energy.......................................................................25 2.1.2 Potential and Kinetic Energy..............................................................................25 2.1.3 Total Energy and Energy Change of a System ......................................................26 2.2 Energy Transfer by Heat, Work or Mass ..................................................................26 2.2.1 Energy Transfer by Heat and by Work.................................................................26 2.2.2 Total Energy of a Flowing Fluid and Enthalpy......................................................31 2.3 Energy Balance for Closed Systems........................................................................32 2.3.1 Energy Balance of a Closed System ....................................................................32 2.3.2 Corollaries of the First Law................................................................................33 2.4 Energy Balance for Open Systems..........................................................................34 2.4.1 Mass Balance for Open Systems.........................................................................34 2.4.2 Energy Balance for Open Systems.......................................................................35 2.4.3 Energy Balance for Steady-Flow Processes ..........................................................36 2–5 Some Steady-Flow Devices in Engineering Practice...............................................38 2.5.1 Turbines and Compressors .................................................................................38 2.5.2 Heat Exchangers...............................................................................................39 2.5.3 Nozzles and Diffusers........................................................................................39 2.5.3 Throttling Devices............................................................................................40
2.5.4 Mixing chambers Chapter 3 Properties and Processes of Ideal-gas 3. 1 The Ideal-gas Equation of State 3.1.1 Ideal Gas and Real Gas 3.2 Specific Heat of Ideal-gas 3. 2. 1 Specific Heat 3. 2. 2 Specific Heat of Ideal-gas 3.3 Internal Energy, Enthalpy and Entropy of ldeal-gas 3.3. 1 Internal Energy and Enthalpy of Ideal-gas 3.2 Entropy of Ideal gases 3. 4 Thermodynamic Analysis on Typical Ideal-gas Processes 3. 4. 1 The Purpose of Thermal Processes Analysis and Methods Adopted 3.4.2 Basic Thermodynamic Processes 3.4.3 Poly-tropic Process 3.5 Ideal-gas Mixtures 3.5. 1 Temperature, Pressure and Volume of Ideal-gas Mixture 3.5.2 The Compositions of Ideal-gas Mixture 3.5.3 The Apparent Molar Mass and the Gas Constant of Ideal-gas Mixture.. 3.5.4 Partial Pressure of a Component 3.5.5 Specific Heat of Ideal-gas Mixture 3.5.6 Total Internal Energy, Enthalpy, and Entropy of Ideal-gas Mixture Chapter 4 The Second Law of Thermodynamics 4.1 Essence and Statements of the Second Law of Thermodynamics 4. 1. 1 Direction of Natural Processes and Irreversibility 4. 1.2 Essence and Statements of the Second Law of Thermodynamics 4.2 The Carnot Cycle 4.2. 1 The Carnot's Cycle 4.2.2 The Carnot Theorems 4.2.3 The Reversed Carnot Cycle and Reversible Cycle among Thermal Reservoirs 4. 3 Entropy and the Increase of Entropy Principle 43. 1 Derivation of Entropy 4.3.2 Clausius Inequality and Entropy Change during an Irreversible Process 4.3.3 The Increase of Entropy Principle 4. 4 Entropy Balance 4. 4. 1 Entropy Generation and Entropy Transfer 4.4.2 Entropy Balance 80 4.5 Exergy and Anergy 4.5.2 Exergy Transfer and Exergy of a System. 4.6 Exergy Analysis 4.6. 1 Exergy Destruction and the Decrease of Exergy Principle 4.6.2 Exergy Balance Equation 4.6.3 Exergy Efficiency
4 2.5.4 Mixing Chambers.............................................................................................40 Chapter 3 Properties and Processes of Ideal-gas.................................................................42 3.1 The Ideal-gas Equation of State...............................................................................42 3.1.1 Ideal Gas and Real Gas......................................................................................42 3.1.2 Ideal-gas Equation of State.................................................................................42 3.2 Specific Heat of Ideal-gas........................................................................................44 3.2.1 Specific Heat....................................................................................................44 3.2.2 Specific Heat of Ideal-gas..................................................................................45 3.3 Internal Energy, Enthalpy and Entropy of Ideal-gas .................................................50 3.3.1 Internal Energy and Enthalpy of Ideal-gas............................................................50 3.3.2 Entropy of Ideal Gases.......................................................................................50 3.4 Thermodynamic Analysis on Typical Ideal-gas Processes .......................................52 3.4.1 The Purpose of Thermal Processes Analysis and Methods Adopted .........................52 3.4.2 Basic Thermodynamic Processes ........................................................................53 3.4.3 Poly-tropic Process ...........................................................................................58 3.5 Ideal-gas Mixtures...................................................................................................62 3.5.1 Temperature, Pressure and Volume of Ideal-gas Mixture .......................................62 3.5.2 The Compositions of Ideal-gas Mixture ...............................................................63 3.5.3 The Apparent Molar Mass and the Gas Constant of Ideal-gas Mixture .....................64 3.5.4 Partial Pressure of a Component .........................................................................64 3.5.5 Specific Heat of Ideal-gas Mixture......................................................................65 3.5.6 Total Internal Energy, Enthalpy, and Entropy of Ideal-gas Mixture..........................65 Chapter 4 The Second Law of Thermodynamics ..................................................................67 4.1 Essence and Statements of the Second Law of Thermodynamics ...........................68 4.1.1 Direction of Natural Processes and Irreversibility..................................................68 4.1.2 Essence and Statements of the Second Law of Thermodynamics.............................69 4.2 The Carnot Cycle.....................................................................................................70 4.2.1 The Carnot's Cycle ............................................................................................70 4.2.2 The Carnot Theorems........................................................................................72 4.2.3 The Reversed Carnot Cycle and Reversible Cycle among Thermal Reservoirs...........74 4.3 Entropy and the Increase of Entropy Principle .........................................................75 4.3.1 Derivation of Entropy........................................................................................75 4.3.2 Clausius Inequality and Entropy Change during an Irreversible Process...................77 4.3.3 The Increase of Entropy Principle .......................................................................78 4.4 Entropy Balance ......................................................................................................79 4.4.1 Entropy Generation and Entropy Transfer ............................................................79 4.4.2 Entropy Balance ...............................................................................................80 4.5 Exergy and Anergy..................................................................................................83 4.5.1 Introduction .....................................................................................................83 4.5.2 Exergy Transfer and Exergy of a System..............................................................84 4.6 Exergy Analysis .......................................................................................................88 4.6.1 Exergy Destruction and the Decrease of Exergy Principle.......................................88 4.6.2 Exergy Balance Equation...................................................................................91 4.6.3 Exergy Efficiency .............................................................................................92
Chapter 5 Real Gas and Thermodynamic Property Relations 5.1 Real-gas Equation of State 5. 1. 1 Compressibility Factor---A Measure of Deviation from Ideal-Gas Behavior 2 Real Gas Equations of State 5.2 Mathematical Prelimin aries 5.2. 1 Some Formulas involving Partial Differentials Relations 5.2.2 General Relations for Simple Compressible Substances 5. 3 General relations for du dh and d: 5.3. 1 General Relation for Internal Energy Changes 5.3.2 General Relation for Enthalpy Changes 103 5.3.3 General Relations for Entropy Changes 5. 4 The Specific Heats c, and c 5.4.1 Differential Equation of Specific Heats c,and cp 104 5. 4.2 General Relations of Difference between c, and c 5-5 The Joule- Thomson coefficient Chapter 6 Water Vapor 错误!定义书签 6. 1 Vaporization and Condensation 错误!未定义书签 6.2 Phase Change Process of 错误!未定义书签 6.2.1 Phase Change process of Water 错误!未定义书签 6.2.2 Property Diagrams for Phase-Change Processes 错误!未定义书签 6.3 Water Vapor Tables 错误!未定义书签 63 1 Reference State and Reference values 错误!未定义书签。 6.3.2 Types of Steam Tables 错误!未定义书签。 6.3.3 Saturated Liquid-Vapor Mixture 错误!未定义书签。 6. 4 The Enthalpy -Entropy Diagram(h-s Diagram) for Steam 错误!未定义书签。 6.5 Thermodynamic Processes of Water Vapor 错误!未定义书签。 6.5.1 Isochoric Process 错误!未定义书签。 6.5.2 Isobaric Process 错误!未定义书签。 6.5.3 Isothermal Process 错误!未定义书签 6.5. 4 Adiabatic Process 错误!未定义书签 Chapter 7 Atmospheric Air 错误!未定义书签 7.1 Atmospheric Air and State Properties 错误!未定义书签 7. 1. 1 Definition of Atmospheric air(Moist air) 错误!未定义书签 7. 1.2 State of Atmospheric Air and its State Properties 错误!未定义书签 7.2 The Measurement of Relative Humidity 错误!未定义书签 7.3 Psychrometric Chart(h-d Chart) 错误!未定义书签 74 Analysis and Application of Thermodynamic Process of AtmospherIc A错误!未定义 书签。 7.4. 1 Simple Heating Proc 错误!未定义书签。 7.4.2 Simple Cooling Process 错误!未定义书签。 7.4.3 Cooling with Dehumidification 错误!未定义书签
5 Chapter 5 Real Gas and Thermodynamic Property Relations ............................................95 5.1 Real-gas Equation of State......................................................................................95 5.1.1 Compressibility Factor---A Measure of Deviation from Ideal-Gas Behavior .............95 5.1.2 Real Gas Equations of State ...............................................................................96 5.2 Mathematical Preliminaries......................................................................................99 5.2.1 Some Formulas involving Partial Differentials Relations........................................99 5.2.2 General Relations for Simple Compressible Substances ....................................... 100 5.3 General Relations for du, dh and ds....................................................................... 102 5.3.1 General Relation for Internal Energy Changes .................................................... 102 5.3.2 General Relation for Enthalpy Changes.............................................................. 103 5.3.3 General Relations for Entropy Changes.............................................................. 104 5.4 The Specific Heats v c and p c .............................................................................. 104 5.4.1 Differential Equation of Specific Heats v c and p c ............................................... 104 5.4.2 General Relations of Difference between p c and v c ........................................... 106 5–5 The Joule-Thomson Coefficient............................................................................ 106 Chapter 6 Water Vapor ........................................................................... 错误!未定义书签。 6.1 Vaporization and Condensation .................................................... 错误!未定义书签。 6.2 Phase Change Process of Water.................................................. 错误!未定义书签。 6.2.1 Phase Change Process of Water................................................ 错误!未定义书签。 6.2.2 Property Diagrams for Phase-Change Processes......................... 错误!未定义书签。 6.3 Water Vapor Tables ...................................................................... 错误!未定义书签。 6.3.1 Reference State and Reference Values....................................... 错误!未定义书签。 6.3.2 Types of Steam Tables ............................................................ 错误!未定义书签。 6.3.3 Saturated Liquid–Vapor Mixture.............................................. 错误!未定义书签。 6.4 The Enthalpy - Entropy Diagram ( h s − Diagram) for Steam ........... 错误!未定义书签。 6.5 Thermodynamic Processes of Water Vapor .................................. 错误!未定义书签。 6.5.1 Isochoric Process................................................................... 错误!未定义书签。 6.5.2 Isobaric Process..................................................................... 错误!未定义书签。 6.5.3 Isothermal Process ................................................................. 错误!未定义书签。 6.5.4 Adiabatic Process................................................................... 错误!未定义书签。 Chapter 7 Atmospheric Air......................................................................... 错误!未定义书签。 7.1 Atmospheric Air and State Properties............................................ 错误!未定义书签。 7.1.1 Definition of Atmospheric air (Moist air) .................................. 错误!未定义书签。 7.1.2 State of Atmospheric Air and its State Properties........................ 错误!未定义书签。 7.2 The Measurement of Relative Humidity ........................................ 错误!未定义书签。 7.3 Psychrometric Chart ( h d − Chart) ................................................. 错误!未定义书签。 7.4 Analysis and Application of Thermodynamic Process of Atmospheric Air错 误 ! 未定义 书签。 7.4.1 Simple Heating Process .......................................................... 错误!未定义书签。 7.4.2 Simple Cooling Process.......................................................... 错误!未定义书签。 7.4.3 Cooling with Dehumidification................................................ 错误!未定义书签