a numerical study on agglomeration in high temperature fluidized beds

نویسندگان

rahmat sotudeh-gharebagh

navid mostoufi

zahra mansourpour

چکیده

soft-sphere discrete element method (dem) and navier-stokes equations were coupled with equations of energy for gas and solids to investigate the process of agglomeration in fluidized bed of polyethylene particles at high temperature. the newton’s second law of motion was adapted for translational and rotational motion of particles and agglomerates. the cohesive force for polyethylene particles was calculated based on a time dependent model for solid bridging by the viscous flow mechanism. the motion of agglomerates was described by means of the multi-sphere method. by taking into account the cohesiveness of particles at high temperatures and considering real dynamic agglomerates, the fluidization behavior of a bed of polyethylene particles was successfully simulated in terms of increasing the size of agglomerates. effect of the inlet gas temperature on mass and size of agglomerates was investigated. a mechanistic study in terms of contact time, cohesive force and repulsive force, which are the key parameters in the formation of agglomerates, were also carried out.

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عنوان ژورنال:
journal of chemical and petroleum engineering

ناشر: university of tehran

ISSN

دوره 48

شماره 1 2014

میزبانی شده توسط پلتفرم ابری doprax.com

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