Cascade Refrigeration System / Cascade System

-: Cascade Refrigeration System :- 

When the Vapour Compression System is to be used for the production of low temperature then that system is known as cascade system or cascade refrigeration system . 

            In cascade system , a series of refrigerants with progressively lower boiling temperature are used . A schematic arrangement of a two stage cascade system as shown in figure - 

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The cascade refrigeration system consists of two or more vapour compression refrigeration system in series which use refrigerants with progressively lower boiling temperatures . In cascade refrigeration system , a cascade condenser serves as an evaporator for the high temperature cascade system and as a condenser for the low temperature cascade system . The only useful refrigerating effect is produced in the evaporator of the low temperature evaporator of the low temperature cascade system . 

                 The difference in low temperature cascade temperature and high temperature cascade evaporator temperature is called temperature overlap . If these temperature are equal , then it is known as intermediate temperature .