Hydrodynamic characteristics of jet‐spouted beds
Hydrodynamic characteristics of jet‐spouted beds
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射流床的水动力特性
DOI:
10.1002/cjce.5450610318
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发表时间:
1983
影响因子:
2.1
通讯作者:
W. Kaminski
中科院分区:
文献类型:
--
作者:
A. Markowski;W. Kaminski
Jet-spouted beds characterised by high velocity gas jets (above 1.7 Umsl), and shallow bed depths H0 of around 2 D1 were investigated on laboratory scale beds and industrial scale beds and the results obtained thereof are correlated and presented in this work. Compared with the classical spouted beds, important differences in bed structure, solid movements and basic hydrodynamic characteristics were observed. The minimum spouting velocity, bed voidage and pressure drop during stabilized spouting are described in terms of dimensionless equations. Bed expansion was used as the basis for the classification of different jet-spouting regimes (incoherent spouting, fast spouting, pneumatic conveying) and changes in the slope of the bed expansion curve are correlated with regime changes. This classification could be useful in the optimization of industrial scale jet-spouted beds. A typically applicable regime of fast spouting was identified.
On a etudie a l'echelle du laboratoire et a lechelle industrielle les lits “spouted” par jets, caracterises par des jets de gaz a vitesses elevees (excedant 1.7 Umsl) et des profoneurs (H0) faibles d'environ 2 D; les correlations etablies pour les resultats obtenus sont presentees dans ce travail. Si l'on compare ces lits avec les lits “spouted” classiques, on observe qu'il existe des differences importantes dans la structure du lit, les mouvements des solides et les caracteristiques hydrodynamiques fondamentales. On decrit, a l'aide d'equations sans dimensions, la vitesse minimale du “spouting”, le degre de vide du lit et la perte du charge durant un “spouting” stabilise. On a employe l'expansion du lit comme base d'une classification des differents regimes de “spouting” par jets (“spouting” incoherent, “spouting” rapide et transport pneumatique) et l'on a etabli des correlations entre les variations dans la pente de la courbe d'expansion du lit et les changements de regime. La classification precitee pourrait s'averer utile dans l'optimisation des lits “spouted” par jets a echelle industrielle. On a identifie un regime de “spouting” rapide applicable dans des conditions typiques.