Multi-scale modelling of fluidized bed biomass gasification using a 1D particle model coupled to CFD

For many fluidized bed applications, the particle movement inside reactor is accompanied by reactions at scale. The current study presents for first time in literature a multi-scale modelling approach coupling one-dimensional volumetric model with dense discrete phase (DDPM) of ANSYS Fluent via user defined functions. To validate developed approach, uses experimental data pressure drop, temperature and gas composition obtained lab-scale bubbling biomass gasifier. Therefore, previously pyrolysis was modified implementing heat transfer valid conditions as well kinetics char gasification taken from literature. kinetic theory granular flow used to describe particle–particle interactions allowing feasible calculation times level whereas an optimized solver employed guarantee fast solution level. A newly initialization routine initial reacting particles different states conversion calculated standalone version model. This allows start simulation very close stable operation reactor. coupled over 30 s process employing 300.000 inert parcels about 25.000 fuel showed good agreement time. Furthermore, in-depth analysis processes track individual while resolving gradients particle.