Prediction of batch heat transfer coefficients for pseudoplastic fluids ...

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The es tima ted accuracy is ± 17% fu"'1d ± 2076 for the jacket
and coil respectively.
There are five criticisms or limitations to this
1-1ork.
1. The Hall velocity term t.!aS chosen on an unsound
basis.
2. The viscosity term in the Reynolds and Prandtl
numbers does not take into account changes of apparent
viscosity with changes in agitation rate.
3. Only one impeller was used.
~-. The viscosity range covered is limited.
5. The viscosity ratio term does not revert to the
one generally accepted for Newtonian fluids as
fLoo approaches fLo
ltJork of Salamone et al (165)
The second Hork on this subject, dealing with jacketed
vessels only, was done by J. J. Salamone, A. Cristaldi, and
A. Korn.
Salamone et ale studied the heat transfer characteristics
of power-law pseudoplastics, Hith flow behavior indexes varying
from 0.33 to 0.77, in a 12 inch diffi~eter
stainless steel
vessel, using a four inch flat bladed turbine with six blades.
The heat transfer runs Here of the unsteady state variety
and the Hilson plot method was used to calculate the batch
heat transfer coefficient. The results were cross plotted