Understand the basic principles of air compressors, such as screw compressors and piston compressors.
Working Principle of an Air Compressor
22 June 2021
Anair compressor is a machine which converts power (using an electric motor, diesel or gasoline engine) into potential energy stored in high pressure air. At Atlas Copco, we develop and carry out a self-contained manufacturing process for every air compressor engine that we market.
Type of air compressors are generally based on working principles
The air compressor uses several principles to work;
There are two general principles for compressed air (or gas):
Positive displacement compression
Positive displacement compressors include reciprocating compressors (piston), orbital compressors (scroll) and various types of rotary compressors (screw, tooth and vane). In positive displacement compression, the air is drawn into one or more compression chambers, which are then closed from the inlet. The volume of each chamber decreases gradually and the air is compressed internally. When the pressure has reached the designed built-in pressure ratio, the port or valve is opened and the air is expelled to the outlet system as the volume of the compression chamber continues to decrease.
Dynamic compressors work in the basis of converting the velocity head of the gas into pressure. The most common dynamic compressors are the centrifugal compressors also known as turbo compressors. Based on the flow direction related to the compressor impeller they can be split in axial or radial flow pattern. Dynamic compressors are designed for large volume flow rates. And they can include several compression stages. During dynamic compression, air is drawn between the blades on a fast rotating compression impeller and accelerates to a high speed. Gas is the expelled through a diffuse, where the kinetic energy is converted into static pressure.