Dispersion large deviation from plug flow

Figure 4.10.57 Experimental set-up for open vessel boundary condition (a) and F functions for a large extent of dispersion (high deviation from plug flow) for an open vessel (b) and closed vessel (c) for different values of 6o = uL/Dax-Adapted from Levenspiel (1999).

This model can be used whenever the dispersion model is used and for not too large a deviation from plug flow both models give identical results, for all practical purposes. Which model you use depends on your mood and taste. 

In conclusion then, it would seem that for small deviations from plug flow, both the dispersion and the tanks-in-series models will give satisfactory results. Up to the present, which one is used may be largely a matter of personal preference. 

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