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

16
of fit and it may t...herefore be concluded that bot.h. methods
can be used to characterize the apparent viscosity with equal
success ..
The use of the semi-empirical equation is some1tlhat
easier; because there are only tlNO constants, lNhich vary
from impeller to impeller.
Some of the constants in the
theoretical equation could be averaged but there are large
variations in the Reynolds nu..mber exponents vJhich would lead
to rather large errors if averaged.
It may be argued, h01;J'­
ever, that Hhether theT'e are tlNO or five constan"ts, one l'11"ill
probably have to look them up and thus the actual number
of constants is limnaterial.
The Correlation C has a distinct advantage over Correlation
G since it has a fundamental basis. The use of l/(n + 1)
as a factor in the exponent of the Reynolds number of the
semi-empirical equation has no fundamental basis. The use
of 1/nO.75 in the exponent of the consistency ratio was
purely empirical also.
It is thus the belief of the author
that Correlation C is the better of the two correlations
and is recommended for use.