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

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C il _,
aI' b l
, cl' dl, el, fl' gl, hI' and jl are all
constants to be evaluated.
The group to the left of the equal sign is called the
POv-Ter number.
The first group to the right is the mixing
Reynolds nmnber, and the second group to the l"ight is the
Froude number. The Froude n~unber is required to account
for the vortex formation in a s\-lirling system.
Thus if
baffles or off-center impeller location is used the Froude
number is not needed.
Host authors have also neglected the
remaining groups and have specified a different value of
C4 for each change in geometry. The effects of impeller
style, blade Hidth, number of blades, impeller pitch,
impeller clearance, Dt/Da, and spacing of multiple impellers
have been studied by Bates et al. (12)..
Richards (158) has
studied the effect of impeller spacing, nurnber and 1.ddth
of baffles, number and vddth of impeller blades, and the
effects of coils.
Host of the Horl~
on non-iJel.Jtonian systems has been
similar but not as extensive.. BrOv.ffi and Petsiavas (31)
have investigated the mixing of Bingham plastics. They
found the P01-Jer number \hTaS
a function of the Reynolds,
Froude, and Hedstrom numbers.