Abstract
A numerical investigation is conducted on secondary flows and roll-cell instabilities in the laminar channel flow of dilute polymer solutions subjected to a steady spanwise rotation. Finite difference calculations of the full nonlinear equations of motion for a Maxwell fluid and a Rivlin-Ericksen fluid of the second grade are presented which indicate that there is a double-vortex secondary flow at weak and rapid rotation rates with an instability in the form of longitudinal roll cells at intermediate rotation rates (regimes analogous to those for a Newtonian fluid). However, for a given physical pressure gradient and rotation rate, the introduction of a minute amount of a polymeric additive to a Newtonian fluid so that the Weissenberg number is of the order of 10-5 has a stabilizing effect on rotating channel flow and gives rise to secondary flows with a substantially reduced frictional drag. Comparisions with previously conducted experimental and analytical studies are made along with a brief discussion of potential applications to the field of polymeric drag reduction.
Original language | English |
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Pages (from-to) | 17-40 |
Number of pages | 24 |
Journal | Acta Mechanica |
Volume | 60 |
Issue number | 1-2 |
DOIs | |
State | Published - Jun 1986 |