Rv. Venkat et Jj. Chalmers, CHARACTERIZATION OF AGITATION ENVIRONMENTS IN 250 ML SPINNER VESSEL, 3 L, AND 20 L REACTOR VESSELS USED FOR ANIMAL-CELL MICROCARRIER CULTURE, Cytotechnology, 22(1-3), 1996, pp. 95-102
Three dimensional particle tracking velocimetry (3-D PTV) was used to
characterize the flow fields in the impeller region of three microcarr
ier reactor vessels. Three typical cell culture bioreactors were chose
n: 250 mi small-scale spinner vessels, 3 L bench-scale reactor, and 20
L medium-scale reactor. Conditions studied correspond to the actual o
perating conditions in industrial setting and were determined based on
the current scale-up paradigm: the Kolmogorov eddy length criterion.
In this paper we present characterization of hydrodynamics on the basi
s of flow structures produced because of agitation. Flow structures we
re determined from 3-D mean velocity results obtained using 3-D PTV. A
lthough the impellers used in 3 L and 20 L reactors were almost identi
cal, the flow structures produced in the two reactors differed conside
rably. Results indicate that near geometric scale up does not necessar
ily amount to scale-up of flow patterns and indicates that intensity a
s well as distribution of energy may vary considerably during such a s
cale-up.