Hydraulic Analysis

Compressor Power Calculation

This web application calculates power required by a centrifugal compressor for isentropic compression.

Gas Data

Gas Flowrate, Q

m³/s

Gas Molecular Weight, MW

Ratio of Specific Heats of Gas, k

Suction Pressure of Gas, P1

kPag

Discharge Pressure of Gas, P2

kPag

Suction Temperature of Gas, T1

° C

Compressibility of Gas at Suction Condition, Z1

Compressibility of Gas at Discharge Condition, Z2

Formula Used

\displaystyle \displaystyle H_{p} = \frac{1545}{MW}\frac{Z_{avg}T_1}{(n-1)/n}\left[ \left(\frac{P_2}{P_1}^{(n-1)/n}-1\right)\right]

where, Hp is polytropic head in ft-lb_f/lb_m

\displaystyle \displaystyle \frac{n}{(n-1)} = \left[\frac{k}{(k-1)}\right]\eta_p

\displaystyle \displaystyle Power(hp) = \frac{(w)(H_p)}{(\eta_p)(33,000)}

where, w is weight flow in lb/min

\displaystyle \displaystyle T_2 = T_1\left(\frac{P_2}{P_1}\right)^{(n-1)/n}

where, T₂ is discharge temperature

Result

Reference