In this post I want to share you how to calculate *centrifugal compressor power* since there are so many process engineers are looking for it (and I also don’t know how).

To calculate centrifugal compressor power, we need these gas properties: compressibility factor (Z), molecular weight (MW), inlet gas temperature, inlet gas pressure, outlet gas pressure, adiabatic component (Cp/Cv), and mass flow rate.

Let’s start with an example while I show you step-by-step of the calculation method. In this example, we have these gas properties (I use US units).

*Compressibility factor*** (Z)** = 0.9972

*Molecular weight*** (MW)** = 18.15

*Gas constant ***(R)** = 1544/molecular weight

*Inlet temperature ***(T1)** = 546 deg R

*Inlet pressure*** (P1)** = 15 psia (don’t forget to use absolute pressure)

*Outlet pressure ***(P2)** = 60 psia

**K** (Cp/Cv) = 1,274

*Flow ***(W)** = 0,184 lb/min

The required data to calculate centrifugal compressor power is **head**. We can use either adiabatic head or polytropic head as long as we use adiabatic efficiency and polytropic efficiency in companion. Read More