Rp. Mun et al., THE EFFECTS OF POLYMER CONCENTRATION AND MOLECULAR-WEIGHT ON THE BREAKUP OF LAMINAR CAPILLARY JETS, Journal of non-Newtonian fluid mechanics, 74(1-3), 1998, pp. 285-297
The breakup of viscoelastic jets has been investigated for a series of
dilute and semidilute poly(ethylene oxide) solutions. The solvent com
position was varied in order to maintain a nearly constant viscosity a
nd surface tension for all fluids, while the apparent extensional visc
osity increased with molecular weight. Photographs of the jets showed
that for the fluids with low apparent extensional viscosities, the bre
akup length for low-velocity jets was similar to that of a Newtonian f
luid with the same viscosity and surface tension. At higher velocities
, a previously unreported decrease in the breakup length relative to t
he Newtonian fluid was observed. For the fluids with high extensional
viscosities, the breakup length increased with increasing molecular we
ight and became independent of concentration. Satellite droplets were
only suppressed in the cases where the breakup length was increased. (
C) 1998 Elsevier Science B.V.