Flow behavior of solid phases is simulated by means of DEM-CFD in a liquid-solid fluidized bed with magnetization of preliminarily fluidized bed (LAST) mode along an axial uniform magnetic field. By changing the magnetic field strength, the distribution of particles is studied within the bed. The distributions of velocity and concentration of ferromagnetic particles are analyzed at the different magnetic field intensities. When the magnetic field strength is increased to a value at which the fluidization of strings starts, the particles are found to form straight-chain aggregates along the direction of the magnetic field. At very high magnetic field strengths, the defluidization is observed at which particles are fixed in the bed. Simulations indicate that the granular temperature of particles increases, reaches a maximum, and then decreases with the increase of magnetic-flux density. The moderate strength magnetic field gives a high fluctuation of particles. The predicted solid pressure increases with the increase of concentration of particles. (C) 2012 Elsevier B.V. All rights reserved.