CO2 Refrigeration Cycle and Systems

Preface
Contents
1 CO2 Refrigeration Cycle and Systems
1.1 Introduction
1.1.1 The Challenge and Trend of Refrigeration
1.1.2 CO2—A Potential Natural Refrigerant
1.2 The Purpose and Content of this Book
References
2 Natural Refrigerants and Carbon Dioxide
2.1 Existing Refrigerant Fluids
2.2 Requirements for Working Fluids
2.3 Natural Working Fluids
2.3.1 Ammonia
2.3.2 Air
2.3.3 Water
2.3.4 Hydrocarbons
2.4 Carbon Dioxide (CO2) Fluid
2.4.1 Thermodynamic and Transport Properties
2.4.2 Applications of R744-based Refrigeration Systems
2.5 Historical Choice and Future of CO2 Fluid
2.6 Conclusion
References
3 Transcritical CO2 Refrigeration Cycle and Systems
3.1 Properties of CO2 Pure Substances
3.2 Refrigeration Machine and Heat Pump
3.3 Reversed Carnot Cycle
3.4 Basic Characteristics of CO2 Refrigeration Cycles
3.4.1 Classification of CO2 Refrigeration Cycles
3.4.2 Transcritical CO2 Refrigeration Cycle
3.5 Various CO2 Refrigeration Thermodynamic Cycles
3.5.1 The Single-Stage Cycle with an Internal Heat Exchanger (SCI)
3.5.2 The Single-Stage Cycle with an Expander (SCE)
3.5.3 The Double-Stage Cycle with a Gas Intercooler (DC)
3.5.4 The Double-Stage Cycle with Two Evaporators (DW)
3.5.5 The Double-Stage Cycle with a Closed Flash Intercooler (DCFI)
3.5.6 The Double-Stage Cycle with an Open Flash Intercooler (DOFI)
3.5.7 The Cascade System
3.5.8 Transcritical CO2 Reversible System
3.5.9 Subcooling
3.6 Equivalent Temperature Method
3.6.1 Lorentzen Cycle
3.6.2 Equivalent Temperature
References
4 Theoretical Analysis of Expansion Process and Components in CO2 (Transcritical) Refrigeration System
4.1 Introduction
4.2 CO2 Expansion Fundamental
4.3 Expansion Valves
4.3.1 Introduction
4.3.2 Flow Characteristics of Refrigerant in Expansion Valves
4.3.3 Theoretical and Experimental Studies
4.3.4 Summary of characteristics of CO2 EEV
4.4 Capillary Tube and Analysis
4.4.1 Introduction
4.4.2 Capillary Characteristics
4.4.3 Flow Characteristics of Refrigerant in Capillary Tubes
4.4.4 Calculation of Capillary Length
4.4.5 Analysis
4.5 CO2 Ejectors
4.5.1 Introduction
4.5.2 Ejectors Technology
4.5.3 Transcritical CO2 Ejector-Expansion Refrigeration System
4.5.4 Summary of Characteristics of CO2 Ejector
4.6 Conclusions
References
5 CO2 Gas Cooler and Cooling Process
5.1 Optimal Heat Rejection Pressure
5.2 Prediction of Optimal Heat Rejection Pressure
5.3 Heat Transfer and Hydraulic Analyses
5.3.1 Heat Transfer Coefficient
5.3.2 Pressure Drop
5.3.3 Calculations of Smaller-Diameter Tubes
5.4 Modelling and Performance Evaluation
5.4.1 Distributed Method
5.4.2 Model Validations
5.5 Microchannel CO2 Gas Coolers
References
6 CO2 Evaporation Process Modeling and Evaporator Design
6.1 Introduction
6.2 CO2 Evaporation Heat Transfer and Two-Phase Flow Characteristics Inside Tubes
6.2.1 Thermal Physical and Transport Properties of CO2
6.2.2 Analysis of Experimental Data of CO2 Evaporation Inside Tubes
6.3 A General Gas–Liquid Two-Phase Flow Pattern Map for CO2 Evaporating Inside Tubes
6.4 A General Flow Pattern Based Evaporation Heat Transfer Model for CO2
6.5 A General Flow Pattern Based Two-Phase Frictional Pressure Drop Model for CO2
6.6 The Oil Effect on CO2 Two-Phase Pressure Drops and Evaporation Heat Transfer
6.7 CO2 Evaporator Simulation and Design
6.7.1 CO2 Evaporation and Evaporator Modeling
6.7.2 Simulations of CO2 Thermal Systems Using the Cheng et al Models
6.7.3 CO2 Evaporator Design and Selection
6.8 Concluding Remarks
References
7 CO2 Commercial Refrigeration Cycle and Systems
7.1 Main Features of Commercial Refrigeration and Systems Used
7.2 Evolution from Secondary Refrigerant to All-CO2 Commercial Refrigeration Systems
7.2.1 CO2 as Secondary Fluid
7.2.2 Cascade Systems with CO2
7.2.3 All-CO2 Systems
7.3 System Adaptation to Warm Climates: Main Approaches
7.3.1 Parallel Compression
7.3.2 Ejectors
7.3.3 Flooded Evaporation
7.3.4 Mechanical Subcooling
7.3.5 Other Solutions
7.4 Integration of HVAC Demands into the CO2 Commercial Refrigeration System
7.5 Future Developments and Lines of Research
7.6 Conclusions
References
8 CO2 Refrigeration Cycles and Systems for Ice Rinks and Snowmaking
8.1 Introduction
8.1.1 Ice Characteristics and Applications
8.1.2 Snowmaking
8.1.3 Ice Rink
8.2 CO2 Refrigeration Cycles and Systems for Ice Rinks
8.2.1 Development and State-of-The-Art of CO2 Applications in Ice Rinks
8.2.2 Description and Case Study of CO2 Refrigeration Cycles in Ice Rink Systems
8.2.3 Comparative Remarks on Integrated Ice Rink Energy Systems
8.3 CO2 Refrigeration Cycles and Systems for Snowmaking
8.3.1 Ice Generation
8.3.2 Indoor Snowmaking
8.3.3 Comparative Remarks on Snowmaking Methods with Heat Recovery
8.4 Conclusions
References
9 CO2 Mobile Air Conditioning
9.1 Background of CO2 MAC
9.1.1 History of CO2 MAC
9.1.2 Low GWP Refrigerant Policy
9.1.3 Recent Development
9.2 Characteristics of CO2 MAC
9.2.1 CO2 MAC Structure
9.2.2 Cooling Performance
9.2.3 Influencing Parameters
9.3 Key Components
9.3.1 Compressor
9.3.2 Gas Cooler
9.3.3 Evaporator
9.3.4 Accumulator
9.3.5 Internal Heat Exchanger
9.3.6 Throttling Device
9.4 CO2 Mobile Heat Pump
9.4.1 Conventional CO2 Mobile Heat Pump
9.4.2 Novel SGC CO2 Mobile Heat Pump
9.5 Application in Train, Bus and Container
9.5.1 CO2 Train Air Conditioning
9.5.2 CO2 Bus Air-Conditioning
9.5.3 CO2 Container Air-Conditioning
References
10 Industrial Cooling Systems
10.1 Introduction
10.2 Thermodynamic Analysis
10.3 Food Industry Cooling
10.4 Power Generation with Refrigeration
10.5 Transport Refrigeration
10.6 Conclusions
References
11 CO2 Trans-Triple-Point Refrigeration Method
11.1 Introduction
11.2 Trans-Triple-Point Refrigeration Method
11.3 CO2 Micro Particle Sublimation Flow Dynamic
11.4 New Cryogenic CO2 Refrigeration Thermodynamic Cycle and Under -56.6 ℃ Refrigeration Using CO2
11.5 Conclusions
References