| As a new kind of reactor, pulsed-fluidized bed (PFB) has the effects on ameliorating bubble influence and improving gas-solid contact. The unique flowing pattern of gas-solid in PFB is one of the most important characters which is different from continuous fluidized bed, and is the foundation of PFB theories and application. Consequently, the investigation on the flowing characteristics of bubbles and particles in the bed is becoming the most important contents in the study of PFB system.Combining the modern information technology and optical technology, image method is a new way to study the formulae of bubbles movement in the PFB. It eliminates the disadvantages of disturbing bed flowing measured by contact apparatus, and is propitious to test the flowing pattern of gas-solid in PFB.In this thesis, based on the self-made experimental platform, we carried out a series of two-dimension cold simulation experiments on gas-solid flow characteristics in the PFB. Using the camera's high speed picture collection quality, we obtain the instantaneous flowing pattern. Through analyzing of pictures and experimental observation, we studied the forming and evolvement of bubbles which changed with frequency ( f ) and pulse width rate ( I ), bubble velocity andparticles mixture characteristic was also involved.Behavior of bubbles is one of the most basic characteristics in gas-solid fluidized bed. The behavior of bubbles apparently affects the hydrodynamics of the bed, the gas-solid mixture, as well as mass and heat transportation. We made a qualitative description of bubbles' formation and evolvement in this paper and gained semi-rational formula of the average bubble accessional velocity in the PFB, meanwhile we discussed the mixture and separating of particles. At a certain extent all of this investigation has practical value for two-phase mathematical modeling, magnificating of the PFB equipments as well as the popularization and application of the PFB technique.
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