What determines the pressure developed by a centrifugal compressor?

The pressure developed by a centrifugal compressor is primarily influenced by the impeller tip speed, which is directly related to the RPM of the motor. As the RPM increases, the impeller rotates faster, causing the fluid to be accelerated more aggressively. This increase in velocity contributes to higher pressure at the discharge of the compressor.

While the diameter of the impeller and the impeller tip speed are important factors, it is the speed at which the impeller is turned (RPM) that fundamentally determines how much energy is imparted to the fluid, thereby affecting the pressure output. The temperature of the refrigerant does play a role in the overall thermodynamic performance of the system, but it does not directly influence the centrifugal compressor’s pressure development in the same way that the RPM does.