How does an Air Compressor Work?


Do you know how an air compressor work and how many compressor types there it is in the market? It only takes 6 minutes to read this article, and understand how it works and the different types of compressor.

There exists a variety of different compressor type:

Positive displacement Compressors (air drawn in a chamber, then compressed by reducing the volume of the chamber)

  • Rotary (Lobe, Screw, Vane, Scroll & Liquid Ring)
  • Reciprocating (Double acting, Single acting & Diaphragm)

Dynamic Compressors (air is accelerated to high velocity, then passed through a diffuser)

Normally the compressors that are used in the field of automation and workshops are the so called positive-displacement compressors. So on those compressors, the pressure is excited when air is drawn in a chamber and the volume of this chamber is reduced.

This is a simple overview about different types of air compressors working principle of a single stage piston compressor, also called reciprocating compressor.

By having a closer look at the reciprocating  compressor, the crankshaft turns, a piston reciprocates within the cylindrical housing.

A totally different working principle has the so called rotary compressor, also named as vane compressor. This typical rotary compressor has a cylindrical housing. Adjustable rotary vanes with its center point on an offset drive shaft have contact with the housing. So when the shaft rotates these vanes create chamber of variable sizes. Air is sucked into the largest chamber, being compressed and leaves the compressor at the smallest chamber.

In addition, these compressors are quiet and relatively insensitive to dirt. It's used in this typical industries:

  • Wastewater treatment;
  • Fish Breeding Aeration;
  • Dust Collection;
  • Vacuum Packing;
  • And more.

Centrifugal compressors have such a wide range for applications. By providing high-pressure ratios and large operating ranges with relatively high efficiencies it can be adapted for the industries named above. 

One of the advantages of these compressors, is that they are used primarily for their suitability for handing small volume flows. Other advantages include a shorter length than an equivalent axial flow compressor, less susceptibility to loss of performance by buildup of deposits on the blade surfaces, and their suitability to operate over a wide range of mass flow.

The efficiency of a centrifugal compressor is lower than that of an axial flow compressor. Efficiency is probably the most important performance parameter for turbomachines.