Application of k- and q-space encoding NMR techniques on granular media in a 3D model fluidized bed reactor

被引:21
作者
Harms, S [1 ]
Stapf, S [1 ]
Blümich, B [1 ]
机构
[1] Rhein Westfal TH Aachen, ITMC, D-52074 Aachen, Germany
关键词
granular flow; PGSTE NMR; propagator; dispersion coefficient; velocity imaging;
D O I
10.1016/j.jmr.2005.10.009
中图分类号
Q5 [生物化学];
学科分类号
071010 ; 081704 ;
摘要
A combination of PFG-NMR imaging and velocity encoding methods was applied to investigate the,dynamic behavior of a bed of poppy seeds subjected to air flow, representing a model setup for fluidized bed reactors. The particle motion is described both from a statistical point of view, by determining propagators and dispersion coefficients representing an average over the whole bed volume, as well as combined with spatial resolution by generating velocity maps. Velocity images of different horizontal slices in the bed confirm the notion of a toroidal particle flow pattern inside the shallow granular bed. Despite the need of considerable averaging due to the random motion of the relatively few particles in the bed, quantitative velocity images and statistical information about the random particle motion can be obtained from monitoring the fluid component in the seeds by conventional spin-echo techniques. (c) 2005 Elsevier Inc. All rights reserved.
引用
收藏
页码:308 / 317
页数:10
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