Computational study of heat transfer in a bubbling fluidized bed with a horizontal tube

Authors

  • Q. F. Hou,

    1. Laboratory for Simulation and Modelling of Particulate Systems, School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
    Search for more papers by this author
  • Z. Y. Zhou,

    1. Laboratory for Simulation and Modelling of Particulate Systems, School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
    Search for more papers by this author
  • A. B. Yu

    Corresponding author
    1. Laboratory for Simulation and Modelling of Particulate Systems, School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
    • Laboratory for Simulation and Modelling of Particulate Systems, School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
    Search for more papers by this author

Abstract

A combined approach of discrete particle simulation and computational fluid dynamics is used to study the heat transfer in a fluidized bed with a horizontal tube. The approach is first validated through the good agreement between the predicted distribution and magnitude of local heat transfer coefficient with those measured. Then, the effects of inlet fluid superficial velocity, tube temperature and main particle properties such as particle thermal conductivity and Young's modulus are investigated and explained mechanistically. The relative importance of various heat transfer mechanisms is analyzed. The convection is found to be an important heat transfer mode for all the studied conditions. A large convective heat flux corresponds to a large local porosity around the tube, and a large conductive heat flux corresponds to a large number of particle contacts with the tube. The heat transfer is enhanced by the increase of particle thermal conductivity while it is little affected by Young's modulus. Radiative heat transfer becomes increasingly important as the tube temperature is increased. The results are useful for temperature control and structural design of fluidized beds. © 2011 American Institute of Chemical Engineers AIChE J, 2012

Ancillary