What is Refrigeration ?

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The term refrigeration means cooling a space, substance or system to lower and/or maintain its temperature below the ambient one. In other words, refrigeration is artificial cooling. Energy in the form of heat is removed from a low-temperature reservoir and transferred to a high-temperature reservoir.


  • Refrigeration may be defined as the process of achieving and maintaining a temperature below that of the surroundings, the aim being to cool some product or space to the required temperature.
  • One of the most important applications of refrigeration has been the preservation of perishable food products by storing them at low temperatures. Refrigeration systems are also used extensively for providing thermal comfort to human beings utilizing air conditioning.
  • Air Conditioning refers to the treatment of air so as to simultaneously control its temperature, moisture content, cleanliness, odor, and circulation, as required by occupants, a process, or products in the space. 

1. Natural Cooling : 

  • Art of Ice making by Nocturnal Cooling
  • Evaporative Cooling
  • Cooling by Salt Solutions
2. Artificial Refrigeration

  • Vapour Compression Refrigeration Systems
  • Vapour Absorption Refrigeration Systems
  • Solar energy based refrigeration systems
  • Gas Cycle Refrigeration
  • Steam Jet Refrigeration System
  • Thermoelectric Refrigeration Systems
  • Vortex tube systems

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