A device used to compress air,or some other gas or vapor, for mechanical
or electrical power production, and in air
conditioners, heat pumps, and refrigerators
to pressurize the refrigerant thus enabling it to flow through the system.
Compressors are closely related to pumps: both increase the pressure on
a fluid and both can transport the fluid through a pipe. As gases are compressible,
the compressor also reduces the volume of a gas, whereas the main result
of a pump raising the pressure of a liquid is to allow the liquid to be
transported elsewhere. Compressing a gas naturally increases its temperature.
| Air compressor.
Credit: VHT Engineering
|A rotary compressor in which the pressure of a gas
is increased by trapping it between vanes which reduce it in volume
as the impeller rotates around an axis eccentric to the casing: (a)
diffuser; (b) casing; (c) impeller; (d) water coolant.
Types of compressor
Reciprocating compressors have a cylinder in which runs
a piston driven by a crankshaft; their principle of operation is similar
to that of a pump. Simple rotatry compressors have a rotating
cylinder mounted eccentrically in a cylindrical casing. Vanes are mounted
on the cylinder such that they slide in and out of slots as comprelled by
the walls of the chamber. Gas is introduced at one side of the chamber and
drawn round by the vanes; the volume between cylinder and chamber decreases
as the cylinder turns, and thus pressurized gas is released at the outlet
on the other side of the chamber.
REFRIGERATION, AND AIR CONDITIONING