Numerical Simulation Of Flow Behavior Of Gas And Particles In Rotating Fluidized Bed

Fluidized-bed reactors are widely used in combustion, chemical and biochemical processes, including polymerization. To enhance the efficiency of the fluidized bed reactors, more flexibility in controlling the residence time of particles of different sizes, particularly very fine particles, is needed. To achieve this goal, we studied gas and particle flow patterns in a vertical and horizontal rotating fluidized bed (RFB).Flow behavior of gas phase in the rotating fluidized bed is simulated. Profile of velocity and pressure of gas phase is predicted. Results indicate that the tangential component of gas velocity is low in the center, increases towards the walls, reaches maximum and then decreases near the walls. The effect of inlet gas velocity on pressure and flow fields is studied. Results show that the tangential velocity of gas is decreased that indicate the intensity of rotation is dropped along height.For flow of gas and particles in the rotating fluidized bed, we limit our study to the quasi-three-dimensional simulation of an isothermal rotating fluidized bed with constant particle size and no chemical reaction to examine the predictability of a computational fluid dynamics approach to the analysis of rotating fluidized bed systems. We use 200- ? mparticles as the particulate phase and air as the gas phase in our simulation. The instantaneous velocity, volume fraction, and pressure drop profiles for the gas and particulate phases are calculated. Effect of inlet gas velocity on distribution of particles and concentration is studied. Simulation results show that the particulate residence time distribution could be controlled by the manipulation of inlet gas velocity.