  Liquid holdup and mass transfer area are critical parameters for packed
column design and CO2 capture efficiency prediction. In this paper, a framework
was established for modeling the liquid-gas countercurrent flow hydrodynamics
in a random packed column with pall rings. Besides the column-averaged
information, the radial pall ring distribution, velocity, and liquid holdup
profiles are obtained to study the entrance effect and the wall influence in
the packed column. With local CFD data, the validated packing specific area ap
and liquid velocity uL range for liquid holdup correlation is significantly
expanded with respect to existing experimental or column-averaged CFD data. The
proposed liquid holdup correlation $h_L \propto u_L^{0.44}$ indicates the
random packed column falls in a viscous to turbulent transition regime and it
covers a Reynolds Number range of [6.7-40.2]. The derived liquid holdup
correlation is in good agreement with existing correlations developed using the
column-averaged experimental data.
