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

1/
for:m.ed using:
(a all the paddle data including 241 data points
at twelve different positions; 154 of these
points vJere for one height ..
(b tHO data points for each paddle height.
The i'irst test used all the data available but may have been
biased since 64 percent of th.e data was for one height value
and some heights were represented by only two data points.
Rence the second set of data points was tested using the
same amount of data for each point.
In the first test (all available data) the Nusselt
. (/) 0.32
number was i'ound to be a i'unctlon of HCR HL
where
HCR is the height of the center of the impeller above the
vessel floor and RL is the liquid height..
In the second
test the Nussel t number ·Has found to be a function of
(H CH /H L )O.45. ~lliile neither test is entirely satisfactory
because of the data limitations, the exponent of this impeller
height ratio can be estimated to be somEH-Jhere betl.reen
these two values, or rou&hly 0.4. It is interesting to note
that this effect, not previously studied, is more important
than the Prandtl number or viscosity ratio for equal changes
of the variables.
CORRELATIONS
The major portion of the data collected in tl1.is thesis
(453 data points) 11as used to evaluate the constants for