الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Fluidization occurs when a gas or liquid is forced to flow vertically through a bed of particles at such a rate that the buoyed weight of the particles is completely supported by the drag force imposed by the fluid. Most applications of fluidized beds are for cases where the fluidizing fluid is a gas, rather than a liquid. Hence, the resent work is devoted to consideration of fluidized beds where the fluidization is caused by upward flow of a gas. In this study a mathematical model and numerical simulation were developed for two dimensional fluidized bed with uniform fluidization. The model consists of two sub models for hydrodynamic and thermal behavior of fluidized bed. A FORTRAN program entitled is devolved. The program is used to predict the volume fraction of gas and particle phases, the velocity of the two phases, the gas pressure and the temperatures distribution for two phases. Also, the program clculates the heat transfer coefficient, nusselt number, reynolds number, flow number, archimedes number, dimensionless gas velocity and desity number. In addition, the program predicts the fluidized bed to achieve the best thermal behavior. The hydrodynamic model is verified by comparing its results with MFIX code. while the thermal model was tested and compared with the available previous empirical correlations. A theoretical correlation was developed to link the hydrodynamic and thermal behavior of the fluidized bed. The results of the present model show very good agreement with MFIX results. it is also found that the average heat transfer coefficient increases with the decrease in particles terminal velocity, particles diameter and minimum fluidized velocity. The total pressure DROP across the bed increases with the increase of particles diameter as well. It is worth mentioning that, the present model describes well the hydrodynamic and thermal behavior of fluidization for group A, group B and group D under uniform fluidization.