Industrial & Engineering Chemistry Research, Vol.56, No.1, 87-99, 2017
Contact Modifications for CFD Simulations of Fixed-Bed Reactors: Cylindrical Particles
One of the major issues for particle-resolved CFD simulations of fixed beds are particle-particle and particle-wall contacts. A fixed bed of cylinders is studied with different local contact modifications (i.e., caps and bridges method for line and area contacts, and caps and united method for overlaps resulting from composite DEM particles). Effects are analyzed regarding pressure drop, local velocity, and local heat transfer for 191 < Re-p < 763. Modeling particle-wall contacts is becoming more important with increasing Re-p. Contact modifications inside the bed are becoming less important because convective heat transfer is dominant. The stable caps method. shows promising results in comparison with heat-transfer predictions. However, it overestimates convective heat transfer in the contact regions for high flow rates. The bridges method shows good results for pressure drop and heat-transfer predictions. A difficulty remains the choice of the thermal conductivity of these bridges.