HYDRODYNAMIC SIMULATION AND EXPERIMENTAL STUDIES OF AN INTERNALLY CIRCULATING BUBBLING FLUIDIZED BED WITH CONCENTRIC CYLINDERS

J P SImanjuntak

Abstract


This paper presents hydrodynamic simulation and experimental studies of gas–solid flow in an internally circulating bubbling fluidized bed (ICBFB) using concentric cylinders. An Eulerian–Eulerian Model (EEM) incorporating the kinetic theory of granular flow (KTGF) was applied in order to simulate the gas–solid flow behavior. The gas and solid dynamic was simulated using a computational fluid dynamics (CFD) software package, Fluent 6.3. Three–dimensional (3D) geometry was used to represent the key parts of a pilot scale of this reactor. Simulations were conducted to investigate the effect of the changes of six operating parameters: the fluidization flow rate of the draft tube (Qdt), the aeration flow rate of the annulus (Qan), the initial bed static height (Hbs), the draft tube height (Hdt), the draft tube diameter (Ddt), and the orifice diameter (Dor) on the solid flow characteristics in terms of the solid circulation rate (Gs). The results were then validated with the experimental results. All the investigated operating parameters have strong effect on Gs.

 

Keywords: Concentric cylinders fluidized bed; Solid circulation rate; Finite volume approach; ANSYS/Fluent


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