DEM--CFD modeling and simulations of hydrodynamic characteristics and
flow resistance coefficient in fixed-bed reactors
Abstract
The ability to predict void fraction, pressure drop, and flow resistance
coefficient in fixed-bed reactors is significant to their optimal
design. In this study, the discrete element method (DEM) is combined
with computational fluid dynamics (CFD) to simulate the hydrodynamic
characteristics of fixed-beds. A realistic random packing structure for
fixed-beds with spherical particles was generated via the DEM method and
then meshed using Ansys ICEM software for the CFD simulation. A grid
independency study was performed to select appropriate grid model
parameters. A large set of numerical experiments was conducted to
investigate the hydrodynamic characteristics with respect to different
inlet velocities and particle sizes, and the simulated pressure drop
data were used to calculate the flow resistance coefficient. The output
flow resistance coefficients agreed well with those calculated by the
classical models in laminar and turbulent flow regimes, thereby
indicating the accuracy and advantage of the proposed DEM–CFD approach.