  Liquid spreading in gas-liquid concurrent trickle-bed reactors is simulated
using an Eulerian twofluid CFD approach. In order to propose a model that
describes exhaustively all interaction forces acting on each fluid phase with
an emphasis on dispersion mechanisms, a discussion of closure laws available in
the literature is proposed. Liquid dispersion is recognized to result from two
main mechanisms: capillary and mechanical (Attou and Ferschneider, 2000;
Lappalainen et al., 2009- The proposed model is then implemented in two
trickle-bed configurations matching with two experimental set ups: In the first
configuration, simulations on a 2D axisymmetric geometry are considered and the
model is validated upon a new set of experimental data. Overall pressure drop
and liquid distribution obtained from $\gamma$-ray tomography are provided for
different geometrical and operating conditions. In the second configuration, a
3D simulation is considered and the model is compared to experimental liquid
flux patterns at the bed outlet. A sensitivity analysis of liquid spreading to
bed geometrical characteristics (void-fraction and particles diameter) as well
as to gas and liquid flow rates is proposed. The model is shown to achieve very
good agreement with experimental data and to predict, accurately, tendencies of
liquid spreading for various geometrical bed characteristics and/or phases
flow-rates.
