title: Elastic instabilities of polymer solutions in cross-channel flow.
abstract: When polymer molecules pass near the hyperbolic point of a microchannel cross flow, they are strongly stretched. As the strain rate is varied at low Reynolds number (< 10(-2)), tracer and particle-tracking experiments show that molecular stretching produces two flow instabilities: one in which the velocity field becomes strongly asymmetric, and a second in which it fluctuates nonperiodically in time. The flow is strongly perturbed even far from the region of instability, and this phenomenon can be used to produce mixing.
authors.affiliation: Physics Department, Haverford College, Haverford, PA 19041, USA.
authors.forename: P E
authors.initials: PE
authors.lastname: Arratia
authors.forename: C C
authors.initials: CC
authors.lastname: Thomas
authors.forename: J
authors.initials: J
authors.lastname: Diorio
authors.forename: J P
authors.initials: JP
authors.lastname: Gollub