Understanding Centrifugal Air Compressors

Centrifugal air compressors are driven by impellers to rotate at high speed, so that the gas generates centrifugal force. Due to the expansion and pressure flow of the gas in the impeller, the flow rate and pressure of the gas after passing through the impeller are increased, and compressed air is continuously produced.
Features
Centrifugal air compressors are speed compressors. When the gas load is stable, centrifugal air compressors work stably and reliably.
①Compact structure, light weight, large exhaust volume range;
②Fewer wearing parts, reliable operation, and long life;
③The exhaust is not contaminated by lubricating oil, and the air supply quality is high;
④High efficiency and energy saving when the displacement is large.
Working principle
Centrifugal air compressors are mainly composed of two parts: rotor and stator. The rotor includes an impeller and a shaft. There are blades on the impeller, as well as a balance disc and part of the shaft seal. The main body of the stator is the casing (cylinder), and the stator is also equipped with a diffuser, a bend, a returner, an exhaust pipe, an exhaust pipe and part of the shaft seal. The working principle of the centrifugal compressor is that when the impeller rotates at high speed, the gas rotates with it. Under the action of centrifugal force, the gas is thrown into the diffuser behind, and a vacuum zone is formed at the impeller. At this time, fresh gas from the outside enters the impeller. The impeller rotates continuously, and the gas is continuously sucked in and thrown out, thereby maintaining the continuous flow of gas.
Centrifugal air compressors rely on changes in kinetic energy to increase the pressure of the gas. When the rotor with blades (i.e., the working wheel) rotates, the blades drive the gas to rotate, transfer work to the gas, and make the gas gain kinetic energy. After entering the stator part, due to the expansion effect of the stator, the speed energy pressure head is converted into the required pressure, the speed is reduced, and the pressure is increased. At the same time, the guiding effect of the stator part is used to enter the next stage of the impeller to continue to increase the pressure, and finally discharged by the volute. For each compressor, in order to achieve the required design pressure, each compressor is equipped with a different number of stages and sections, and even consists of several cylinders.