Abstract: Basing on the analysis of the forces on magnetic particles, applying the basic theory of the fluidized bed and analyzing by the dimensionless method, the paper shows that the stable zone in a magnetically fluidized bed mainly depends on Re, Ar, and Er, which are primary factors to show the fludized characteristics of the magnetically fluidized bed.A relationship to express the ratio of minimun bubbling velocity to initial fluidized velocity is obtained through the processing of experimental data.Compared with the results reported before, the relationship proves to be correct on the condition of moderate intensity of the magnetic field, and the error of all experimental and calculated data is less than 8%.

Key words: magnetically fluidized bed, stable zone, fluctuation of pressure drop, minimum bubbling velocity