Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2010-11-19
Journal of Rheology, 55 (2011) 1007
Physics
Condensed Matter
Soft Condensed Matter
16 pages, 11 figures, revised version submitted to Journal of Rheology
Scientific paper
10.1122/1.3610169
Spatially inhomogeneous shear flow occurs in entangled polymer solutions, both as steady state shear banding and transiently after a large step strain or during start up to a steady uniform shear rate. Steady state shear banding is a hallmark of models with a non-monotonic constitutive relation between total shear stress and applied shear rate, but transient banding is sometimes seen in fluids that do not shear band at steady state. We model this behavior using the diffusive Rolie-Poly model in a Newtonian solvent, whose constitutive behavior can be monotonic or non-monotonic depending on the degree of convected constraint release (CCR). We study monotonic constitutive behaviour. Linear stability analysis of start up to a sufficiently high shear rate shows that spatial fluctuations are unstable at early times. There is a strong correlation between this instability and the negative slope of the (time dependent) constitutive curve. If the time integral of the most unstable eigenvalue is sufficiently large then the system exhibits transient shear bands that later vanish in steady state. We show how perturbations, due to fluctuations or the inhomogeneous stresses, can trigger this instability. This transient behavior is similar to recent observations in entangled polymer solutions
Adams James M.
Fielding Suzanne M.
Olmsted Peter D.
No associations
LandOfFree
Transient shear banding in entangled polymers: a study using the Rolie-Poly model does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Transient shear banding in entangled polymers: a study using the Rolie-Poly model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transient shear banding in entangled polymers: a study using the Rolie-Poly model will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-116892