Harrison and Leung model for spherical bubble formation in fluid&d beds has been extended to account for the dynamics of the emulsion phase. The simplified Davidson-Harrison model is used to obtain the gas and particle velocities in the emulsion phase sad includes the effect of the bubble oressure.
Mechanism of formation of gas bubble-beds
β Scribed by G. Houghton; A.M. McLean; P.D. Ritchie
- Publisher
- Elsevier Science
- Year
- 1957
- Tongue
- English
- Weight
- 974 KB
- Volume
- 7
- Category
- Article
- ISSN
- 0009-2509
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β¦ Synopsis
Data are presented on the size, number, and size-distribution of bubbles in fluid&d bubble-beds and foam beds. These types of bed differ in that bubble diameter and bubble density (i.e. the number of bubbles per ml) tend to become constsnt for the former as the superficial g8s velocity is increased, whereas bubble density tends to decrease and bubble diameter to increase for the latter. Also, fosm beds are sensitive to the size, number, and distribution of the pores in the gss distributor, whereas fluidized beds are not. R&sum&-Lea autemz prdsentent des dorm&es sur la dimension, le nombre et la rdp8rtition suivant la grosseur, des bulles d8n.s lea " lits Ruidises par bulles " et d8ns les lits de mousses. Ces deux types de lits diff&ent, au le dhunetre des bulles et leur concentration (c'est-Mire le nombre de bulles par ems) tendent 8 devenir constxmts pour lea premiers quand la vitesse superficielle du gaz augmente, tandis qne pour lea seconds, le dian&re des bull-tend & augmenter et leur concentration tend ir. diminuer. Par ailleura, lea lits de mousse sont sensibles 8 Is dimension, au nombre et 8 la r6p8rtition des pores du distributeur de gaz, alors que les lits flmdist!s ne le sont pas. Zusammenfassung-Fi die Grijsse, Zahl und Gtissenverteilung von Blasen in fluidisierten Blasenbetten und in Schaumbetten werden Zahlenwertc mitgeteilt. Diese beiden Bett-Typen unterscheiden sich in folgendem : Blasendurchmesser und Blasendichte (Anzahl der Blasen je ml) werden im ersteren Falle konstant mit steigender Gasgeschwindigkeit, besogen auf den Bett-Querschnitt, im zweiten Falle nimmt die Blasendichte ab und der Blasendurchmesser zu. Schsumbetten sind such empfindlich gegeniiber der Gtisse, Zahl und Verteilung der Poren des Anstri)mbodens, in Gegensstz zu den fluidisierten Betten.
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## Shorter Communications characteristic time of the fluid Greek symbols natural time of the fluid radial, angular and axial component of the % velocity, respectively second invariant of the rate of deformation tensor