Refrigeration and Cold Storage

Course Objective:
To develop basic concept and fundamental knowledge of air compressor, refrigeration system, psychrometry and cold storage

1. Thermodynamic Cycles  (4 hours)
1. Carnot Cycle for Refrigeration
2. Reverse Carnot Cycle
3. Conclusion from Carnot Cycle
4. Refrigerator and Heat Pump
5. Coefficient of Performance (COP)

2. Reciprocating Air Compressor (8 hours)
1. Air Compressor Terminology
2. Primary Components of a Reciprocating Air Compressor
3. Working Principle of Reciprocating Air Compressor
4. Work Done by Compressor
5. Volumetric and Adiabatic Efficiencies
6. Multi-stage Compression
7. Intercoolers
8. Representation of p-V and T-s diagrams
9. Clearance Volume Effects
10. Condition for Minimum Work

3. Other Compressors  (6 hours)
1. Rotary Compressors
2. Hermetic Sealed Compressors
3. Centrifugal Compressors
4. Axial flow Compressors
5. Power Required to Drive a Compressor
6. Velocity Diagrams
7. Losses and Efficiencies of compressors
8. Application of Compressors

4. Refrigeration System  (8 hours)
1. Introduction
2. Unit of Refrigeration
3. Air Refrigeration System
4. Simple Vapour Compression Refrigeration System: Ideal and Actual Vapour Compression Cycles, T-s and p-h Diagrams, Effects of Dry Compression and Wet Compression, Coefficient of Performance
5. Multi-Stage Refrigeration System
6. Cascade Refrigeration System
7. Vapour Absorption Refrigeration System: Vapour Absorption Cycle,
8. Electrolux Refrigerator

5. Evaporators: Types, Function, Capacity of an Evaporator, Factors Affecting the Heat Transfer Capacity (4 hours)

6. Condensers: Types, Function, Factors Affecting the Condenser Capacity, Heat Rejection Factor, Cooling Towers and Spray Ponds  (4 hours)

7. Expansion Devices: Types, Construction and Functions. (2 hours)

8. Refrigerants  (6 hours)
1. Classification
2. Properties: Ideal, Physical and Chemical
3. Environment Friendly Refrigerants

9. Principle of Psychometrics  (10 hours)
1. Psychrometric Properties
2. Phychometric Processes
1. Sensible Heating and Cooling
2. Cooling and Dehumidification
3. Heating and Humidification
4. Humidification and Dehumidification
5. Mixing of Two Streams of Air
6. Evaporative Cooling/ Adiabatic Humidification
3. Phychrometric Chart and Its Use
4. Comfort Conditions
5. Air-conditioning Systems


10. Cold Storage  (8 hours)
1. Introduction
2. Functional Requirements of Cold Storage
3. Condition of Storage for Perishable Products
4. Calculation of Cooling Load
5. Design of Cold Storage System

Practical:

1. Studies on Parallel Flow and Counter Flow Heat Exchangers
2. Performance Evaluation of Reciprocating Air-Compressor
3. Study on Components and Processes of Vapour Compression and Vapour Absorption Type Refrigeration System
4. Determination of Coefficient of Performance of Vapour Compression and Vapour Absorption Type Refrigeration System
5. Experimentation on Refrigeration Tutor, Humidifier and Heat Pump to Determine Coefficient of Performance and Efficiency
6. Calculation of Cooling Loads
7. Determination of Heat Transfer Coefficient inside a Cold Storage and Refrigerator.
8. Determination of Pull Down Characteristics of a Cold Storage.

References:

1. C. P. Arora, “Refrigeration and Air-Conditioning”, Tata McGraw Hill Book Co. Ltd, New Delhi, India.
2. Manohar Prasa, “Refrigeration and Air-Conditioning”, Wiley Eastern Publishers, New Delhi, India.
3. Roy J. Dossat, “Principles of Refrigeration”,. Wiley Eastern Publishers, New Delhi, India.
4. McQuistion and W. Tauker, “Heating, Ventilation and Air-Conditioning”,Wiley Eastern Publishers, New Delhi, India.

Evaluation Scheme:
The questions will cover all the chapters of the syllabus. The evaluation scheme will be as indicated in the table below: