Effects of Drag Models on the Hydrodynamics and Heat Transfer in a Conical Fluidized Bed Combustor

Title & Authors
Effects of Drag Models on the Hydrodynamics and Heat Transfer in a Conical Fluidized Bed Combustor
Kang, Seung Mo; Abdelmotalib, Hamada; Ko, Dong Guk; Park, Woe-Chul; Im, Ik-Tae;

Abstract
In this study, wall to bed heat transfer and hydrodynamic characteristics in a conical fluidized bed combustor was investigated using computational fluid dynamics method. A two-fluid Eulerian-Eulerian model was used with applying the kinetic theory for granular flow(KTGF). The effects of the two drag models, Gidaspow and the Syamlal-O'Brien model, different inlet velocities($\small{1.4U_{mf}{\sim}4U_{mf}}$) and different particle sizes on the hydrodynamics and heat transfer were studied. The results showed that the hydrodynamic characteristics such as bed expansion ratio and pressure drop were not affected significantly by the drag models. But the heat transfer coefficient was different for the two drag models, especially at lower gas inlet velocities and small particle sizes.
Keywords
Computational Fluid Dynamics;Fluidized Bed Combustor;Heat Transfer Coefficient;Drag Model;
Language
Korean
Cited by
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