Chemical Research in Chinese Universities ›› 2002, Vol. 18 ›› Issue (2): 117-120.

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CFD Model of Dense Gas-solid Systems in Jetting Fl uidized Beds

Kai Zhang1, Jiyu Zhang1, Biiang Zhang1, John Yates2   

  1. 1. Institute of Coal Chemistry, Chinese Academy of Sciences, P. O. Box 165, Taiyuan 030001, P. R. China;
    2. Department of Chemical Engineering, University College London, London, WC1E 7JE, UK
  • Received:2001-11-06 Online:2002-04-24 Published:2011-08-04
  • Supported by:

    Supported by National Natural Science Foundation of China(No.29476262) and Royal Society of London.

Abstract: A CFD code has been developed based on the conservation principles describing gas and solid flow in fluidized beds. This code is employed to simulate not only the spatiotemporal gas- and solid-phase velocities and voidage profiles in a two-dimensional bed but also fluid dynamics in the jet region. The computational results show that gas flow direction is upward in the entire bed accompanied with random local circulations, whilst solid flow direction is upward at the center and downward near the wall. The radical reason of strong back-mixing of solid particles and good transfer behavior between two phases is that the jet entrains solid particles. Numerical calculation indicates that gas velocity, solid velocity and pressure profile have a significant change when the voidage is 0. 8. The simulated time-averaged voidage profiles agree with the experimental results and simulated data reported by Gidaspow and Ettehadieh(1983). Therefore, CFD model can be regarded as a useful tool to study the jet characteristics in dense gas-solid fluidized beds.

Key words: Jetting fluidized bed, CFD model, Gas-solid dynamics, Modified SIMPLE