Compressors and Vacuum Pumps
 Fans are used to raise the pressure about 3% (12 in. H20); blowers are used for differentials of about 40 psig; and compressors for higher differentials.
 Theoretical adiabatic horsepower:
Phpt = (FT1/8,130a)((P2/P1)a1) where Phpt = power, hp; F = flowrate, scfm; T1 = inlet temperature, R; P2 and P1 = outlet and inlet pressures, psia; a = (k1)/k, where k = ratio of specific heats.
 Outlet temperature: T2 = T1(P2/P1)a
