Van Winkle's Correlation is an empirical formula that predicts the Murphree plate efficiency for distillation columns separating binary systems. Both system variables and plate parameters are included, and the correlation can be applies to bubble-cap and sieve plates. The equation is:
E = 0.07(Dg^(0.14))(SC^(0.25))(Re^(0.08))
where Dg is liquid diffusivity, Sc Schmidt number, and Re Reynolds Number.
Dg = surface tension number = (σL/µLuv ),
uv = superficial vapor velocity,
σL = liquid surface tension,
µL = liquid viscosity,
Sc = liquid Schmidt number = (µL/ρ_L * D_LK),
ρL = liquid density,
DLK = liquid diffusivity, light key component,
Re = Reynolds number = (hwuvρv/µL(FA)),
hw = weir height,
ρv = vapor density,
(FA) = fractional area = (area of holes or risers)/(total column cross-sectional area)