Recommendations for Agitated Vessels

Since agitated vessels are so common, it is worth noting some points arising from recent work that lead to recommended designs for turbulent systems. Most of this work has been with sparged systems, bnt the remarks on impeller blade shapes may also apply to self-inducers. 

A vessel of larger aspect ratio may be required, for example, to  

In this case, more than one impeller will be required (see Section 11-2.3.3). 

A single upflow hydrofoil may not be optimum in a vessel with H = T, if the D/T ratio is larger than say 0.5 (which may occur if high P/pV is required), since recirculation will be localized and zones of high local gas fraction will be formed.  

3 Multiple Impellers. In vessels taller than H/T = 1.2, or when Reynolds numbers are below about 5000, additional impellers may be required. These would improve the liquid mixing, but also, especially in the heterogeneous 

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