TY - JOUR
T1 - On the apparent viscosity of a fluidized bed
AU - Gibilaro, L. G.
AU - Gallucci, K.
AU - Di Felice, R.
AU - Pagliai, P.
N1 - Funding Information:
The financial support of the Ministero dell’Istruzione, dell’Universita’ e della Ricerca (MIUR) under their PRIN 2003 and 2005 programmes is gratefully acknowledged.
PY - 2007/1
Y1 - 2007/1
N2 - The fluid-dynamic analogy of a typical spherical particle in a fluidized bed as the same particle suspended under terminal conditions in a pseudo-fluid (composed of the fluid and all the other suspended particles) is shown to yield predictive estimates for the apparent viscosity of fluidized beds, in good quantitative agreement with reported experimental measurements for particle concentrations of up to ∼ 40 %. For higher concentrations the predictions fall progressively below measured values, leading to order-of-magnitude underestimates for dense beds at close to minimum fluidization conditions. This latter phenomenon might be ascribable to the dominance, under these conditions, of particle-particle interactions. At high particle concentrations, these would give rise to the observed phenomenon of liquid- and gas-fluidized bed apparent viscosities approaching very similar values, and gas pressure having no influence at all.
AB - The fluid-dynamic analogy of a typical spherical particle in a fluidized bed as the same particle suspended under terminal conditions in a pseudo-fluid (composed of the fluid and all the other suspended particles) is shown to yield predictive estimates for the apparent viscosity of fluidized beds, in good quantitative agreement with reported experimental measurements for particle concentrations of up to ∼ 40 %. For higher concentrations the predictions fall progressively below measured values, leading to order-of-magnitude underestimates for dense beds at close to minimum fluidization conditions. This latter phenomenon might be ascribable to the dominance, under these conditions, of particle-particle interactions. At high particle concentrations, these would give rise to the observed phenomenon of liquid- and gas-fluidized bed apparent viscosities approaching very similar values, and gas pressure having no influence at all.
KW - Apparent viscosity
KW - Fluidization
KW - Pseudo-fluid
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U2 - 10.1016/j.ces.2006.08.030
DO - 10.1016/j.ces.2006.08.030
M3 - Article
AN - SCOPUS:33751015416
VL - 62
SP - 294
EP - 300
JO - Chemical Engineering Science
JF - Chemical Engineering Science
SN - 0009-2509
IS - 1-2
ER -