The document provides an overview of refrigeration systems, focusing on vapour compression and absorption refrigeration methods, along with their advantages. It details the types of refrigerants used, specifically chlorinated fluorocarbons, and introduces key concepts like the assessment of cooling effects and the coefficient of performance (COP). The content includes equations and measures related to refrigeration efficiency and performance assessment.

2. TOPIC :
REFRIGERATION……

3. CONTENTS:
 INTRODUCTION…
 TYPE OF REFRIGERATION…
 ASSESSMENT OF REFRIGERATOR…

4. INTRODUCTION

5. VAPOUR COMPRESSION
REFRIGERATION

6. Overview:
• Highly compressed fluids tend to get colder when
allowed to expand.
• If pressure is high enough:
 Compressed air hotter than source of cooling.
 Expanding gas cooler than desired cold temperature.

7. Advantages:
 A lot of heat can be removed (lot of thermal energy to
change liquid to vapour).
 Heat transfer rate remains high ( temperature of
working fluid much lower than what is being cooled).

8. Diagram:

9. Types Of Refrigerant:
 Refrigerant determined bt the required cooling
temperature.
 Chlorinated fluorocarbons (CFCs)
 Or freons : R-11 .

10. VAPOUR ABSORPTION
REFRIGERATION

11. Diagram:

12. ASSESSMENT OF REFRIGERATION

13. Cooling Effect :
 Tons of Refrigeration :
1 TR = 3024 kcal/hr heat rejected.
TR = Q x Cp X x (Ti – To) / 3024

14. Coefficient of Performance (COP):
 Standard measure of refrigeration efficiency.
• Depends on evaporator temperature Te and
condensing temperature Tc:
COP = Te / (Tc – Te)
• COP in industry calculated for type of compressor:
COP = Cooling effect (kw)/power input(kw)

15. Graph Comparison of COP:

16. Bibliography :
 WIKIPEDIA…….
 INTRODUCTION TO MECHL. ENGG…