Expansion Scaling and Elastic Moduli of Gas-Fluidized Magnetizable Beds

Application of Wallis stability criterion and Rietema’s concept
  • J. Y. Hristov
Conference paper
Part of the NATO Science Series book series (NAII, volume 134)


The magnetic field assisted fluidization (MFAF) concerns a fluidization of magnetic solids controlled by external magnetic fields, see Hristov [9,10]. Generally, the particle bed does not operate under compression but under extension due to fluid drag forces, see Lee [12] and Hristov [7]. This chapter concerns the elastic modulus concept, see Rietema and Piepers [18] and Poletto and Massimilla [16], and the effect of the interparticle forces on it. The strong interparticle magnetic forces (see Figure 31.1 (a)‘A’ hinder the fluidization and the bed exhibits a ‘meta’ stable state free of bubbles and mixing motions with bed expansion (see Figure 31.1 (a)‘B’ ) in small steps. The external field ‘induces’ (see Figure 31.1 (a)‘C’) particle arrangements along the field lines, thus changing the structure of the porous medium and its hydrodynamic performance. This ‘meta’ state is commonly named ‘magnetically-stabilized bed’ (MSB), see Figure 31.1 (a)‘D’


Field Intensity Continuity Wave Interparticle Force Particle Arrangement Emerge Technology 
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© Springer Science+Business Media Dordrecht 2004

Authors and Affiliations

  • J. Y. Hristov
    • 1
  1. 1.Department of Chemical EngineeringUniversity of Chemical Technology and MetallurgyBulgaria

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