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Heat and Thermodynamics Course Science and Reactor Fundamentals –Heat &Thermodynamics 1 CNSC Policy Planning and Learning HEAT AND THERMODYNAMICS Revision 1 – March 2003 Science and Reactor Fundamentals – Heat and Thermodynamics 2 SNCS Policy Planning and Learning TABLE OF CONTENTS 1 OBJECTIVES .....................................................................................................................................4 1.1 INTRODUCTION..............................................................................................................................4 1.2 REACTOR AND HEAT TRANSPORT SYSTEM NORMAL OPERATION: ..............................................4 1.3 HEAT TRANSPORT SYSTEM COMPONENT OPERATION: ................................................................5 2 HEAT AND THERMODYNAMICS – THE BASICS.....................................................................6 2.1 BASIC DEFINITIONS AND UNITS ....................................................................................................6 2.1.1 Internal Energy .....................................................................................................................6 2.1.2 Enthalpy and Specific Enthalpy ............................................................................................7 2.1.3 Work......................................................................................................................................8 2.1.4 Heat.......................................................................................................................................8 2.1.5 Temperature..........................................................................................................................9 2.1.6 Entropy and Specific Entropy ...............................................................................................9 2.1.7 Sensible And Latent Heat; Specific Sensible And Latent Heat ...........................................10 2.1.8 Summary of the Key Concepts in Section Basic Definitions and Units ..............................13 2.2 THERMODYNAMIC PROPERTIES OF VAPOUR AND WATER.........................................................15 2.2.1 Behaviour Under Applied Heat...........................................................................................15 2.2.2 Definitions...........................................................................................................................16 2.2.3 Critical Point And Effects Of Pressure On Saturation Conditions.....................................17 2.2.4 Vapour Quality And Moisture Content ...............................................................................20 2.2.5 Summary of the Key Concepts -Thermodynamic Properties of Vapour and Water............21 2.3 THERMODYNAMIC LAWS ............................................................................................................22 2.3.1 The First Law Of Thermodynamics ....................................................................................22 2.3.2 The Second Law of Thermodynamics..................................................................................24 2.3.3 Summary of Key Concepts in Section Laws of Thermodynamics........................................25 2.4 HEAT TRANSFER .........................................................................................................................25 2.4.1 Radiation.............................................................................................................................26 2.4.2 Conduction..........................................................................................................................27 2.4.3 Convection ..........................................................................................................................30 2.4.4 Heat Transfer by Vapour Condensation .............................................................................32 2.4.5 Summary of Key Concepts in Section Heat Transfer ..........................................................33 2.5 REVIEW QUESTIONS – THE BASICS.............................................................................................35 3 REACTOR AND HEAT TRANSPORT SYSTEM NORMAL OPERATION ...........................36 3.1 INTRODUCTION............................................................................................................................36 3.2 REACTOR THERMAL POWER .......................................................................................................37 3.2.1 Definition ............................................................................................................................37 3.2.2 Thermal Power Calculation................................................................................................38 3.2.3 Reactor Power and Temperature Differential ....................................................................40 3.2.4 Summary of Key Concepts in Reactor Thermal Power.......................................................41 3.3 MODES OF FUEL COOLING ..........................................................................................................41 3.3.1 Heat Transfer Processes .....................................................................................................41 3.3.2 Critical Heat Flux and Critical Channel Power.................................................................46 3.3.3 Coolant Boiling...................................................................................................................48 3.3.4 Summary of Key Concepts in Modes of Fuel Cooling ........................................................49 3.4 TEMPERATURE PROFILES IN THE REACTOR CORE ......................................................................50 3.4.1 Fuel Temperature Profile....................................................................................................51 3.4.2 Coolant Temperature and Heat Flux Profile......................................................................53 Revision 1 – March 2003 Science and Reactor Fundamentals –Heat &Thermodynamics 3 CNSC Policy Planning and Learning 3.4.3 Summary of Key Concepts in Temperature Profiles in the Reactor Core...........................60 3.5 REVIEW QUESTIONS – HEAT TRANSPORT SYSTEM.....................................................................62 4 HEAT TRANSPORT SYSTEM COMPONENT OPERATION..................................................65 4.1 INTRODUCTION............................................................................................................................65 4.2 PRIMARY HEAT TRANSPORT SYSTEM PRESSURE CONTROL.......................................................65 4.3 BLEED CONDENSER.....................................................................................................................66 4.3.1 Non-Condensable Gases In Bleed Condenser ....................................................................68 4.4 PRESSURIZER...............................................................................................................................68 4.4.1 Pressurizer Level Control ...................................................................................................70 4.4.2 Summary of Key Concepts PHT System Pressure Control .................................................70 4.5 INTRODUCTION TO BOILERS........................................................................................................71 4.5.1 Boiler Water Level ..............................................................................................................71 4.5.2 Steady State Shrink and Swell.............................................................................................72 4.5.3 Transient Shrink and Swell .................................................................................................73 4.5.4 Boiler Level Control............................................................................................................75 4.5.5 Improper Boiler Water Level ..............................................................................................76 4.5.6 Summary Of Key Concepts In Section Boiler Water Level .................................................77 4.5.7 Boiler Pressure ...................................................................................................................78 4.5.8 Boiler Pressure And Heat Transfer ....................................................................................80 4.5.9 Boiler Pressure During PHT System Warm-Up And Cool-Down ......................................82 4.5.10 Summary Of Key Concepts In Section Boiler Pressure ......................................................85 4.6 REVIEW QUESTIONS – HTS COMPONENTS .................................................................................87 Revision 1 – March 2003 Science and Reactor Fundamentals – Heat and Thermodynamics 4 SNCS Policy Planning and Learning OBJECTIVES This module covers the following areas pertaining to thermodynamics: • Introduction • Heat and Thermodynamics – The Basics • Reactor and Heat Transport System Normal Operation • Heat Transport System Component Operation Introduction • Define terms, and give units of measurement: temperature, specific heat, enthalpy, specific enthalpy, entropy and specific entropy. • Describe heat transfer processes • State the factors which affect the rate of heat transfer • Describe the manner in which the heat transfer rate is affected: radiation, conduction, and
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