Principle of ice making
All refrigeration equipments are made of four key components; the evaporator, the condenser, the compressor and the throttle valve. Ice machines all work the same way. The function of compressor is to compress low-pressure refrigerant vapor to high-pressure vapor, and deliver it to the condenser. Here, the high-pressure vapor is condensed into high-pressure liquid, and drained out through the throttle valve to become low-pressure liquid. At this point, the liquid is conducted to the evaporator, where heat exchanging occurs, and ice is created. This is one complete refrigeration cycle.
Global Economic Applications
The refrigeration industry employs more than 2 million people worldwide, especially in the service sectors. Refrigeration is necessary for the implementation of many current or future energy sources (hydrogen liquefying for alternative fuels in the automotive industry and thermonuclear fusion production for the alternative energy industries).
(1)The petro-chemical and pharmaceutical industries also need refrigeration, as it is used to control and moderate many types of reactions.
(2)Heat pumps, operating based on refrigeration processes, are frequently used as an energy-efficient way of producing heat.
(3)The production and transport of cryogenic fuels (liquid hydrogen and oxygen) as well as the long-term storage of these fluids is necessary for the space industry.
(4)In the transportation industry, refrigeration is used in marine containers, reefer ships, refrigerated rail cars, road transport, liquefied gas tankers etc.