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

J9
cooling mediu..:m side, the heat transfer wall, and that
caused by fouling (30, 150, 19L~).
If the flofJ rates of
the heat transfer mediurQ are approxliaate1y the S8~e
for
all the heating (or cooling) runs and there is no evidence
of fouling or corrosion of the heating surface the swn of
these three resistances, ERR' may be asswned to be the same
for all heating (or cooling) runs.
Thus equation 1-2 may
be 1,Jri tten as
(2-30
for the heating runs and
(2-31
for the cooling rlms, Hhere ERR and:ERc are the S1-1111S
of the
constant resistances for heating and cooling respectively_
Thus the only factor that changes the overall heat transfer
coefficient, U, is a change in the batch heat transfer coefficient,
h.
Previous authors have reported that h is a function
of the Reynolds number raised to the 2/3 p01-{er.
(2-32
Thus equation 2-30 (or 2-31) may be written
(2-33