Determining the Parameter Cb for Turbulent Liquid Flow

For practical reasons, key importance has been attached to the turbulent flow range, ReL 2, as this is the range mostly used for operating packed columns containing large packing elements in rectification processes under normal pressure and vacuum conditions and/or in pressure rectification and in absorption processes at moderate liquid loads. 

Determining the Parameter Cb,fi for Operating Conditions at Flooding Point 

The correlation between the parameter Cb and the relative gas capacity factor Fv/Fv,f1 and specific liquid load up, acc. to Fig. 4-15, leads to the following correlation at the flooding point  

Equation (4-53) was developed on the basis of approx. 200 experimental values for the test systems air/water, methanol/ethanol, chlorobenzene/ethylbenzene, ethylben-zene/styrene in the pressure range of 33 to 1000 mbar. Their validity for any type of mixture is shown below. 

Equations (4-48) and (4-53) finally lead to the following equation for calculating the pressure drop at the flooding point  

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