Ip. Nagy et Ja. Pojman, SUPPRESSING CONVECTIVE INSTABILITIES IN PROPAGATING FRONTS BY TUBE ROTATION, Journal of physical chemistry, 100(8), 1996, pp. 3299-3304
Density gradients caused by thermal and solutal gradients often cause
double-diffusive and/or Taylor instabilities in propagating fronts. Th
ese instabilities manifest themselves as ''fingering'' that can affect
the front shape and velocity and, in extreme cases, destroy the front
. This is especially a problem with propagating fronts of polymerizati
on when a monomer is used that does not produce a cross-linked polymer
. We have found that it is possible to suppress the fingering by rotat
ing the tube around the long axis of the tube. With the chlorate-sulfi
te system and methacrylic acid polymerization system, we found that th
e front velocities exhibited a fourth-order dependence on the rotation
al frequency, and the front shapes were parabolic. The amplitudes of t
he deviation of the fronts from a planar front exhibited a second-orde
r dependence on the rotational frequency but not exactly as predicted
from the hydrostatic analysis of a rotating fluid.