Techshore Inspection Services -Kochi-Kerala | Vapour Compression Notes
Vapor compression refrigeration cycle is the basic working cycle of a refrigeration system. The vapor-compression refrigeration system uses a circulating medium called refrigerant is the medium which absorbs heat from the space to be cooled and subsequently rejects that heat from the room to outside. Figure describes a typical, single-stage vapor-compression refrigeration system. It have primarily four components: compressor, condenser, thermal expansion valve (also called a throttle valve), and evaporator. Circulating refrigerant enters the compressor in the saturated vapor state and is compressed to a higher pressure, higher temperature vapor. The high temperature, high pressure vapor is then in the superheated vapor and it is at a temperature and pressure at which it can be condensed with cooling water or cooling air flowing across the condenser coil or tubes. The circulating refrigerant then rejects heat from the system and the rejected heat is carried away by either the water or the air according to the medium of cooling used and which is ejected to the surrounding.
The main components in a vapor compression refrigeration system are,
3. Expansion valve.
An air compressor is a mechanical device used to increase the pressure of air. Air compressor forces more and more air to the storage tank that increases the pressure inside the tank. When the tank pressure increases more than the desired upper pressure, the compressor cut off. This air can be utilized for various purposes and when the tank pressure reduced as a result of cyclic operations, the compressor turn on again re pressurize the tank.
TYPES OF COMPRESSOR
Reciprocating compressor uses piston cylinder arrangement which is driven by an electric motor or an internal combustion engine. It can be single acting or double acting, single stage or multi stage.
A centrifugal compressor uses an impeller in a shaped housing which forces the gas to the eye of the impeller, which increases the velocity of the air. A divergent duct converts the velocity energy into pressure energy thus increase the pressure of the output air.