AN MRI STUDY OF DRYING IN GRANULAR BEDS OF NONPOROUS PARTICLES

被引:9
作者
HILLS, BP
WRIGHT, KM
WRIGHT, JJ
CARPENTER, TA
HALL, LD
机构
[1] Institute of Food Research, Norwich Research Park, Colney, Norwich
[2] Herchel Smith Laboratory for Medicinal Chemistry, University of Cambridge School of Clinical Medicine, University Forvie Site, Cambridge, CB2 2PZ, Robinson Way
关键词
IMAGING; DRYING; DIFFUSION; CAPILLARY; TRANSPORT;
D O I
10.1016/0730-725X(94)91237-Q
中图分类号
R8 [特种医学]; R445 [影像诊断学];
学科分类号
1002 ; 100207 ; 1009 ;
摘要
MRI is used to study the role of capillary and gravitational forces in controlling mass transport of water during isothermal drying of granular beds of nonporous particles. A new model is presented that shows how capillary and gravitational forces relate to Fickian diffusion driven by a chemical potential gradient. In granular beds, where capillary and gravitational forces dominate, the image profiles give direct information on the dependence of the degree of saturation on capillary suction pressure. The effects of changing particle size and surface tension on the profiles is investigated quantitatively, and it is shown that high capillary pressures create anomalies in the drying profiles.
引用
收藏
页码:1053 / 1063
页数:11
相关论文
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