Dynamic type compressors are machines in which air or gas is compressed by the dynamic action of rotating vanes or impellers imparting velocity and pressure to the flowing gas. The velocity head is converted into pressure, partially in the rotating element and partially in the stationary diffusers or blades. Two general variations, centrifugal and axial compressors are generally used:
Centrifugal Compressors:
The machine in which velocity and pressure are imparted to the air or gas in a radial direction by one or more impeller – diffuser combination.
Axial Compressors:
The machines in which velocity and pressure are imparted to the air or gas in an axial direction by one or more sets of moving and stationary rows of blades.
Mixed Flow Compressors:
The dynamic machines with impeller, which combine some characteristics of both centrifugal and axial type.
Positive Displacement compressors:
Positive displacement type compressors are machines in which successive volumes of air or gas are confined within a closed space. The pressure is increased as the volume of the closed space is decreased. Four general types, broken down according to the constructional method used to carry out
compression are available:
Reciprocating compressors :
The machines in which the compressing element is a piston following a reciprocating motion in a cylinder.
Rotary lobe compressors:
The machines in which two mating lobe impellers revolve within a cylinder and are prevented from making a contact with each other by timing gears mounted outside the cylinder. The gas is trapped by the lobes, which displace it from intake to discharge.
Rotary slide-vane compressors :
The machines in which longitudinal vanes slide radially in a rotor mounted eccentrically in cylinder. Gas gets trapped in the sliding vanes and is compressed and finally discharged as the rotor moves in the casing having suitable ports.
Rotary liquid piston compressors :
The machines in which water or other liquids are used usually in a single rotating element to compress and to displace the air or gas handled. Although each of the positive displacement types will vary from the other somewhat, they can be grouped together as single class of machines for the purpose of compression with dynamic type compressors.
See Also:
OVERHUNG CENTRIFUGAL COMPRESSORS
OVERHUNG CENTRIFUGAL COMPRESSORS DIAGRAM
Mixed Flow Compressors
Horizontal Split Centrifugal Compressor Diagram
Horizontal Split Centrifugal Compressor detail and operation
Centrifugal Compressors:
Reciprocating compressors :
No comments:
Post a Comment