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Fluidized bed technology is widely used in energy, chemical and other fields, but currently experimental means of multiphase flow in fluidized bed flow, heat and mass transfer in the model amplification , the results and the prediction is still insufficient , and the numerical simulation in addressing these issues can obtain the required complete a variety of data , before the experiment can predict the experimental results , the operation of the bed has guiding significance. Pulsating gas-solid fluidized bed is in general based on adding pulsating flow , reported in the literature to improve its liquidity and ordinary fluidized bed heat and mass transfer characteristics , but more complex flow fluidized state , making it more difficult to study . This article uses computational fluid dynamics (CFD) Fluent software Euler -Euler model has been proven reliable with the current drag force model of turbulence models were simulated , the simulation process using a custom function defines pulsating flow waveform, frequency , amplitude and other parameters , according to the requirements of convergence relaxation factor is selected , the time step and solving methods . Stabilizing effect in the fluidized bed pressure drop after record fluctuations in gas-solid distribution and movement of the bubble behavior ; analyzed with pulsating air pressure fluctuation frequency, waveform relations , the role of the pulsating flow fluidized bed reactor under the bubble generation , growth, integration, such as broken , as well as the bubble behavior and the relationship between the height of the bed ; bed expansion ratio is calculated , rolling over , and the pulsating flow of the fluidized bed overall impact results. Numerical results show that pulsating flow can reduce the initial fluidization velocity fluidized bed , close to the resonance frequency under the effect of pulsing air fluidization effects are significantly improved degree of turbulence in the fluidized bed strengthened; and validate reasonable definition of the bubble , as well as inside the bubble phase in the presence of milk , bubble internal pressure changes are mainly affected by bed height , inside and outside the bubble growth and the impact of mass exchange . Through simulation vectors can be clearly seen in the bubble phase in a fluidized bed under the action of particles within the circulation, for further study of pulsating flow on effect of the fluidized bed lay a foundation.
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