where
η = fractional collection efficiency
k = correlation coefficient whose value depends on the system geometry and operating conditions, typically 0.1 to 0.2, 1000 acf/gal
QL/QG = liquid-to-gas ratio, gal/1000 acf
ψ = Cfppv(dp)2/18ddμ = inertial impaction parameter
pp = particle density
v = gas velocity at Venturi throat, feet per second
dp = particle diameter, feet
dd = droplet diameter, feet
μ = gas viscosity, pounds per foot-second
Cf = Cunningham correction factor