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چکیده
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The application of fluidized bed reactor for polyethylene production, due to its excellent specification of heat and mass transfer, gained significant industrial importance. However, these reactors have some problems. For example, the electrostatic charge generation from particle–particle and particle–wall contacts in gas–solid ?uidized beds is virtually unavoidable. As a result, the particles adhere to the walls of the reactor; and if the operational conditions are close to the melting point of the polymer, it creates a layer on the wall. After a while, these solid layers accumulate on the wall and fall on the distributer plate, leading to blockage of the distributer plate holes. In this study, a multi-?uid Eulerian model with electrostatic model is used to predict the electrostatic effect on the dynamics of fluidized bed. First, the hydrodynamic simulation of fluidized bed containing solid particles at three different sizes without the effects of electrostatic charge was performed. Next, the magnitude of electric potential generated due to charged particles contained in square domain was calculated. Finally, for semi-industrial reactor containing charged particles of three different size ranges, bed expansion, the order of magnitude of electric potential, height, and thickness of the predicted developed layer were obtained.
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