MAGNETIC-RESONANCE-IMAGING OF LIQUID FLOW AND PORE STRUCTURE WITHIN PACKED-BEDS

Citation
Aj. Sederman et al., MAGNETIC-RESONANCE-IMAGING OF LIQUID FLOW AND PORE STRUCTURE WITHIN PACKED-BEDS, Chemical Engineering Science, 52(14), 1997, pp. 2239-2250
Citations number
15
Categorie Soggetti
Engineering, Chemical
ISSN journal
00092509
Volume
52
Issue
14
Year of publication
1997
Pages
2239 - 2250
Database
ISI
SICI code
0009-2509(1997)52:14<2239:MOLFAP>2.0.ZU;2-R
Abstract
Magnetic resonance imaging (MRI) volume- and velocity-measurement tech niques are used to probe structure-flow correlations within the interp article space of a packed bed of ballotini. Images of the three mutual ly orthogonal components of the velocity field are obtained in two per pendicular slices within a bed of 5 mm diameter ballotini packed withi n a glass column of internal diameter 4.6 cm. Comparison of flow image s obtained for two beds of identical column-to-particle diameter ratio but of differing length show that velocity enhancements at the walls of the bed are greater in the shorter, more ordered, bed. A three-dime nsional volume image of each bed is also obtained and analysed to part ition the interparticle space into individual pores and determine the location of pore necks. Correlations between volume flow rate and the surface area of the constrictions (pore necks) within the interparticl e space lie between two limiting behaviours. For pores associated with low local Reynolds number, the volume flow rate through the constrict ions scales as the square of the cross-sectional area of the constrict ion, whereas at the extreme of high local Reynolds number pores show v olume flow rates scaling with cross-sectional area. (C) 1997 Elsevier Science Ltd. All rights reserved.