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

26
rate is proportional to the square of the impeller speed
and the proportionality const~nt
is dependent upon the Dt/Da
ratio (122).
Calderbank and I'-'Ioo-Young (34) report that dilatants
may be correlated by
Da./ )0.5
t = 12.3 ( /Dt N (2-21
Obviously, more 1-Jork must still be done for dilatant fluids
but the shear rate for pseudoplastics, Bingh~m
plastics and
Newtonians may be calculated by equation 2-20.
For the special case of pseudoplastic p01"Ter 1m-IT fluids
the generalized Reynolds nQmber may be calculated.
(2-22
The apparent viscosity is defined by
(2-23
The pOHer Im-J can be expressed by
Therefore
I:::KtVJ'l
(2-4
(2-24
or
/. ) ./J'l-{
/La. =: /{~//.5N (2-25