High-fidelity CFD modeling of particle-to-fluid heat transfer in packed bed reactors

The novel high-fidelity CFD model for packed bed reactors is validated in terms of Nu regarding particle-to-fluid heat transfer. The model is developed to take into consideration the flow of heat, mass and momentum through and around the particles each shaped without geometrical simplification. In the present approach, cylindrical shaped solid geometries are used to bridge particles in or near contact assuming the regions are stagnant. The bridges eliminate narrow gaps between particles and then enable treating hundreds of particles in the model. 220 of spherical particles are randomly packed in a cylindrical tube whose diameter is 4 times larger than particles. The predicted Nu is compared with a correlation, experiments and model predictions in the literature. In the smaller Re range, mesh independent solutions well agree with the literature. In the higher range, the applicable range varies from 200 to 700 depending on mesh density. Meshing strategy for increasing particle is rationally given by means of boundary layer theory.