Fully coupled TFM-DEM simulations to study the motion of fuel particles in a fluidized bed Articles uri icon

publication date

  • September 2015

start page

  • 57

end page

  • 66

volume

  • 134

international standard serial number (ISSN)

  • 0009-2509

electronic international standard serial number (EISSN)

  • 1873-4405

abstract

  • In the present work, novel numerical simulations using a hybrid model are carried out to study the motion of objects, representing fuel particles, in a pseudo-2D fluidized bed. The hybrid model combines the continuum treatment of the gas phase with the possibility to treat different solid phases either as continuum, or discrete. In the present case, both the gas and the dense phase of the bed are modelled as continuum phases, as typically done in two-fluid model simulations, whereas fuel particles are simulated as discrete entities whose movement affects, and can be affected by the dense phase motion (i.e. fully coupled TFM-DEM simulations). The results obtained from the model are qualitatively and quantitatively compared with reported experimental findings available in the literature. Firstly, the motion of the fuel particle with regards to the bubble phase and dense phase is proved to be realistic. Secondly, the location probability of the particle in the simulated bed is calculated and compared with the experimental data. Then, the ballistic path followed by the particle in the freeboard is also compared with experimental measurements. These results show good agreement between experiments and simulation. The numerical results reflect the same behaviour during the ascending and descending motion of the fuel particles as that observed in the experiments. The results also show that the most probable locations of the particles predicted by the simulations are consistent with the experimental findings, both inside the fluidized bed and in the freeboard. Overall, the hybrid model tested shows quite promising results, which indicates the potential usability of the model.

keywords

  • fluidized bed; pseudo-2d; object motion; fuel particle; hybrid model; fully coupled simulation