Pore-Scale Simulation of Transport Processes in Fixed-Beds: Combining a Lattice Boltzmann Cfd Method and a Particle Tracking Method

Modeling and simulation of fixed-bed reactors is usually based on classical pseudo-homogeneous modeling approaches that rely on simplifying assumptions and the use of semiempirical effective parameters, which have been adopted to results obtained from a certain experimental setup. This inevitably leads to problems when trying to perform reliable simulations for a priori predictions and optimization purposes. This applies especially to packed beds of low tube-to-particle diameter ratios, which are used in many applications (e.g. strong exothermic reactions). Here the wall effects are relevant over the entire cross section of the bed and local phenomena dominate. In order to account for the local inhomogeneities, the complete 3D structure of the packing has to be considered and a simulation of the transport processes on a pore-scale level has to be performed.