Mixing and drift in gas-fluidised beds

被引:19
作者
Eames, I
Gilbertson, MA
机构
[1] Univ Bristol, Dept Mech Engn, Bristol BS8 1TR, Avon, England
[2] UCL, Dept Mech Engn, London WC1E 7JE, England
[3] UCL, Dept Math, London WC1E 7JE, England
基金
英国工程与自然科学研究理事会;
关键词
mixing; fluidisation; bubbles; drift; vortices; modelling;
D O I
10.1016/j.powtec.2005.04.036
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
One of the most important aspects of bubbling fluidised beds is the mixing they promote. Rowe et al. demonstrated experimentally that the dominant mechanisms of mixing in the bulk of the bed are drift, or permanent displacement of particles, induced by the bubbles, and the return flow it generates [P. Rowe, B. Partridge, A. Cheney, G. Henwood, E. Lyall, The mechanics of solids mixing in fluidised beds, Trans. Inst. Chem. Eng. 43 (1965) 271-286] [1]. We show how, by combining new results relating drift and dispersion, practical estimates of mixing rates consistent with Rowe's view of mixing can be obtained [P. Rowe, B. Partridge, A. Cheney, G. Henwood, E. Lyall, The mechanics of solids mixing in fluidised beds, Trans. Inst. Chem. Eng. 43 (1965) 271-286] [1]. We also develop Batchelor's vortex model of bubbles in fluidised beds to elucidate aspects of bubble structure. (c) 2005 Elsevier B.V. All rights reserved.
引用
收藏
页码:185 / 193
页数:9
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