Solids movement in liquid fluidised beds—II Measurements of axial mixing coefficients

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Abstract

Values of axial mixing coefficients for glass spheres 0·9 cm dia. fluidised by dimethyl phthalate have been determined. The process has been shown to be predominantly of a diffusion type, with the convection pattern of the solids not exerting a significant influence. The results have been compared with those obtained from Brownian motion theory and from the kinetic theory.

Zusammenfassung

On a calculé la valeur des coefficients de mélange axial pour des sphères en verre de 0,9 cm de diamètre, fluidisées par du phtalate de méthyle. Le procédé apparaît surtout du type de diffusion, le modèle de convection des solides ne déployant pas une influence significative. Les résultats ont été comparés à ceux obtenus de la théorie brownienne du mouvement et de la théorie cinétique.

Die Werte der achsialen Mischkoeffizienten wurden für Glaskugeln von 0,9 cm Durchmesser, die mit Dimethylphthalat aufgewirbelt wurden, bestimmt. Es wurde gezeigt, dass der Prozess vorwiegend ein Diffusionsvorgang ist und dass der Konvektionsverlauf der Feststoffe keinen wesentlichen Einfluss ausübt. Die Ergebnisse wurden mit denjenigen aus der Brownschen Bewegungstheorie und der kinetischen Theorie verglichen.

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There are more references available in the full text version of this article.

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