2Computational Fluid Dynamics (CFD) Research Laboratory, School of Chemical Engineering, Iran University of Science and Technology, Tehran, 16846, Iran
In this study, a pellet scale model was developed for trickle bed reactor utilizing CFD techniques. Drag coefficients were calculated numerically at different velocities and bulk porosities in the case of single phase flow through the dry bed. The simulation results were then compared with the prediction of Kozeny-Carman (K-C) equation. The results indicated that drag coefficients calculated from the square arrangement of cylindrical particles in the pellet scale model were in good agreement with Kozeny-Carman equation prediction; however, triangular arrangement had over prediction comparing with Kozeny-Carman equation. Afterward, the pellet scale model with square arrangement was developed for fully pre-wetted particles which were enveloped with a liquid film. The VOF model was used to investigate the boundary condition on the surface of the static liquid layer. The results of CFD simulation in various gas velocities indicated that, at the adjacent of the particle walls, the no-slip boundary condition was acceptable. This pellet scale model was also in good agreement with the Kozeny-Carman equation.
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