Fluid dynamic simulations using the FENE-P model of polymer physics are compared to those an incompressible Newtonian fluid base case in order understand role elasticity formation vortices a 90° bend narrow channel. The analysis bridges flow behavior purely elastic and that fluid. We evaluated how four dimensionless numbers—Reynolds number (Re), Weissenberg (Wi), viscosity ratio (?), (El)—affec...

This work explains a scaling law of the first Landau coefficient derived Ginzburg-Landau equation (GLE) in weakly nonlinear analysis axisymmetric viscoelastic pipe flows large-Weissenberg-number ($Wi$) limit, recently reported Wan et al. J. Fluid Mech. (2021), vol. 929, A16. Using an asymptotic method, we derive reduced system, which captures characteristics linear centre-mode instability near ...

Using self-designed particle visualization instrumentation, startup shear and step strain tests were conducted under a series of systematically varied rheological and geometrical conditions, and the velocity profiles of three different well-entangled polybutadiene/oligomer solutions were obtained. For startup shear tests, in the regime of entanglement densities up to 89 and Weissenberg numbers ...

The recently discovered centre-mode instability of rectilinear viscoelastic shear flow (Garg et al. , Phys. Rev. Lett. vol. 121, 2018, 024502) has offered an explanation for the origin elasto-inertial turbulence that occurs at lower Weissenberg numbers ( $Wi$ ). In support this, we show using weakly nonlinear analysis subcriticality found in Page 125, 2020, 154501) is generic across neutral cur...

Abstract The introduction of slippery lubricated surfaces allows for the investigation flow highly viscous fluids, which otherwise will hardly move on standard solid surfaces. Here we present study gravity induced motion small drops polymeric fluids deposited inclined viscosity these decreases with increasing shear rate (shear thinning) and, more importantly, they exert normal forces planes per...

The oscillating onset of the Rayleigh–Bénard convection with viscoelastic fluids in a slightly tilted two-dimensional rectangular cavity an aspect ratio Γ = 2 was investigated for first time via direct numerical simulation. A series simulations were conducted plane Rayleigh number (Ra) and tilt angle (α∈[0°, 5°]) three Weissenberg numbers [Wi=(0.1,0.15,0.2)] at fixed Prandtl Pr 7.0. evolutionar...

We examine the role of preshearing on flow properties polymer solutions containing essentially an acrylamide-based copolymer obtained from emulsified emulsion inverted by a surfactant. The were presheared using three methods: (1) Buddeberg disperser, (2) Ultra-Turrax and (3) pressure-driven through capillary. Shearing solution was done under fast to induce high stretching chains thus promote br...

We are concerned here with the effect of added filler particles on the linear and non-linear rheological properties of viscoelastic systems. Whilst the addition of spherical or near-spherical filler particles will almost always increase the level of both the linear and the non-linear viscometric properties (so leading to increases in pressure drops, etc.), we usually find a decrease in the leve...

The powder diffractometer at the Australian National Beamline Facility makes extensive use of imaging plates as a detector system. On this instrument, a Weissenberg screen and translatable imaging plate cassette allow a series of up to 35 complete powder patterns to be taken in rapid succession. The high sensitivity and dynamic range of imaging plates mean that exposure times of as little as tw...