Computational fluid dynamics simulation of bubble size and local gas holdup in stirred vessel

被引:0
作者
Li L.-C. [1 ]
Wang J.-J. [1 ]
Gu X.-P. [1 ]
Feng L.-F. [1 ]
Li B.-G. [1 ]
机构
[1] State Key Laboratory of Chemical Engineering, Zhejiang University
来源
Zhejiang Daxue Xuebao (Gongxue Ban)/Journal of Zhejiang University (Engineering Science) | 2010年 / 44卷 / 12期
关键词
Bubble size distribution; Computational fluid dynamics (CFD); Gas-liquid interfacial area per volume; Gas-liquid stirred vessel; Local gas holdup; Numerical simulation;
D O I
10.3785/j.issn.1008-973X.2010.12.027
中图分类号
学科分类号
摘要
The bubble size and local gas holdup in a stirred vessel with dual impellers were simulated numerically with computational fluid dynamics, in which the Euler-Euler multiphase flow model, multi-reference frame method and a transport equation for bubble number density (BND) function were combined. The effects of bubble coalescence and breakage were involved in the bubble number density function. The numerical results were in good agreement with the experimental values measured with double-tip conductivity probes. The results show that the bubble size and local gas holdup distribution in the stirred vessel are very non-uniform under relatively high superficial gas velocity. The bubble sizes in the impeller discharge region is quite small and increases with the discharge currents of the impeller. Bubbles coalescences play a dominant role in the inter-impeller region and the region above upper impeller. Local gas hold up is much high just behind the baffles and the blades where cavitation forms and in the centre of circulation loop.
引用
收藏
页码:2396 / 2400
页数:4
相关论文
共 17 条
[1]  
Laakkonen M., Mollanen P., Miettinen T., Local bubble size distributions in agitated vessel comparison of three experimental techniques, Chemical Engineering Research and Design, 83, 1, pp. 50-58, (2005)
[2]  
Barigou M., Graves M., A capillary suction probe for bubble size measurement, Measurement Science Technology, 2, 4, pp. 318-326, (1991)
[3]  
Gao Z.-M., Smith J.M., Hans Müller-Steinhagen, void fraction distribution in sparged and boiling reactors with modern impeller configuration, Chemical Engineering and Process, 40, 6, pp. 489-497, (2001)
[4]  
Alves S.S., Maia C.I., Vasconcelos M.T., Et al., Bubble size in aerated stirred tanks, Chemical Engineering Journal, 89, 1-3, pp. 109-117, (2002)
[5]  
Morud K.E., Hjertager B.H., LDA measurements and CFD modeling of gas-liquid flow in a stirred Vessel, Chemical Engineering Science, 51, 2, pp. 233-249, (1996)
[6]  
Bombac A., Zun I., Gas-filled cavity structures and local void fraction distribution in vessel with dual-impeller, Chemical Engineering Science, 55, 15, pp. 2995-3001, (2000)
[7]  
Song Y.-L., Gao Z.-M., Li Z.-P., Experimental study and numerical simulation of gas-liquid flow in a stirred tank with a new multiple impeller, The Chinese Journal of Process Engineering, 7, 1, pp. 24-28, (2007)
[8]  
Venneker B.J., Derksen J.J., Akker H.A., Population balance modeling of aerated stirred vessels based on CFD, AIChE J, 48, 4, pp. 673-685, (2002)
[9]  
Lane G.L., Schwarz M.P., Evans G.M., Predicting gas-liquid flow in a mechanically stirred tank, Applied Mathematical Modeling, 26, 2, pp. 223-235, (2002)
[10]  
Lane G.L., Schwarz M.P., Evans G.M., Numerical modeling of gas-liquid flow in stirred tanks, Chemical Engineering Science, 60, 8-9, pp. 2203-2214, (2005)