基于直接矩积分方法的超细颗粒流态化特性研究

An Euler-Euler two-fluid model was used based on kinetic theory of granular flow to solve particle population balance equation by direct quadrature method of moment (DQMOM). The relationship between particle population and continuity/momentum balance equations was established. Dynamic processes of ultrafine particle motion and coalescence with different initial particle diameters in a fluidized bed were numerical simulated. Concentration and velocity distribution of the agglomerate was analyzed and the variation of moments in bed was studied. Effects of different initial particle diameters on agglomerate concentration distribution were compared. The results show that the time for particle concentration (same particle size) to reach steady state is reduced with the increase of bed height. With the increase of initial particle diameter, the rate of particle concentration decrease rises with the increase of bed height, the time for particle agglomerate size to reach steady state is reduced and particle velocity in bed gradually decreases, and agglomerate accumulation at the bottom of the bed accelerates and the particle concentration and particle size at the bottom of the bed increase.