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Time-dependent plane Poiseuille flow of a Johnson-Segalman fluid
(1999)
We numerically solve the time-dependent planar Poiseuille flow of a Johnson-Segalman fluid with added Newtonian viscosity. We consider the case where the shear stress/shear rate curve exhibits a maximum and a minimum at ...
Mechanism for extrusion instabilities in polymer melts
(1999)
A mechanism for explaining some of the instabilities observed during the extrusion of polymer melts is further explored. This is based on the combination of non-monotonic slip and elasticity, which permits the existence ...
Linear stability diagrams for the shear flow of an Oldroyd-B fluid with slip along the fixed wall
(1998)
We consider the time-dependent shear flow of an Oldroyd-B fluid with slip along the fixed wall. Slip is allowed by means of a generic slip equation predicting that the shear stress is a non-monotonic function of the velocity ...
Annular liquid jets at high Reynolds numbers
(2003)
The flow of annular liquid jets at high Reynolds numbers is analysed by means of the finite element method and the full-Newton iteration scheme. Results have been obtained for various values of the inner to the outer ...
Extrusion of a compressible Newtonian fluid with periodic inflow and slip at the wall
(1996)
We explore a mechanism of extrusion instability, based on the combination of nonlinear slip and compressibility. We consider the time-dependent compressible Newtonian extrudate swell problem with slip at the wall. Steady-state ...
New analytical solutions for weakly compressible Newtonian Poiseuille flows with pressure-dependent viscosity
(2016)
Steady-state, isothermal, Poiseuille flows in straight channels and circular tubes of weakly compressible Newtonian fluids are considered. The major assumption is that both the mass density and the shear viscosity of the ...
Perturbation solution of Poiseuille flow of a weakly compressible Oldroyd-B fluid
(2011)
The isothermal, planar Poiseuille flow of a weakly compressible Oldroyd-B fluid is considered under the assumption that the density of the fluid obeys a linear equation of state. A perturbation analysis for all the primary ...
Laminar axisymmetric flow of a weakly compressible viscoelastic fluid
(2012)
The combined effects of weak compressibility and viscoelasticity in steady, isothermal, laminar axisymmetric Poiseuille flow are investigated. Viscoelasticity is taken into account by employing the Oldroyd-B constitutive ...
Incompressible Poiseuille flows of Newtonian liquids with a pressure-dependent viscosity
(2011)
The pressure-dependence of the viscosity becomes important in flows where high pressures are encountered. Applications include many polymer processing applications, microfluidics, fluid film lubrication, as well as simulations ...
Start-up and cessation Newtonian Poiseuille and Couette flows with dynamic wall slip
(2015)
Analytical solutions are derived for the start-up and cessation Newtonian Poiseuille and Couette flows with wall slip obeying a dynamic slip model. This slip equation allows for a relaxation time in the development of wall ...