Very-low-Re chaotic motions of viscoelastic fluid and its unique applications in microfluidic devices: A review

Viscoelastic flow in an obstructed microchannel at high Weissenberg number

“…Several workers have identified large flow deformation rates and flow curvature as important in viscoelastic instability: Pakdel and McKinley (1996), Burghelea et al (2004), Morozov and Saarloos (2007), Li et al (2012), and consequently, geometries such as serpentine microchannels and micro obstructions are of particular interest in generating localised subcritical mixing for heat transfer enhancement.…”

Flow of concentrated viscoelastic polymer solutions in porous media: effect of MW and concentration on elastic turbulence onset in various geometries

“…In 2000 Groisman and Steinberg 14 coined the term ''elastic turbulence'' to describe a widely observed chaotic instability. 25 McKinley et al 27,28 have proposed a dimensionless parameter, M, to characterise the onset of purely elastic flow instabilities, Elastic turbulence has been observed in a number of situations, 25 including microchannel flow, 26 and has been proposed as a method of mixing within microfluidic devices.…”

Robust simulations of viscoelastic flows at high Weissenberg numbers with the streamfunction/log-conformation formulation

“…Viscoelastic fluids exhibit different flow features as compared to purely viscous fluids, such as turbulence drag reduction [1], elastic instabilities [2,3], and elastic turbulence at low Reynold numbers [4,5]. These viscoelastic effects are magnified in micro-fluidics [6]. To cite but a few examples of applications in polymer processing: viscoelasticity plays a role in the well-known extrudate swelling [7,8] and fracture melt [9,10] phenomena seen in extrusion.…”