We solve the free boundary problem for the dynamics of a cylindrical, axisymmetric viscoelastic filament stretching in a gravity-driven extensional flow for the Upper Convected Maxwell and Oldroyd-B constitutive models. Assuming the axial stress in the filament has a spatial dependence provides the simplest coupling of viscoelastic effects to the motion of the filament, and yields a closed syst...

Introduction Inertial effects are ubiquitous and unavoidable in stress-controlled rheometry. Many readers of this Bulletin will have seen the kind of phenomena shown in the experimental data of Figure 1. If the fluid is sufficiently viscoelastic, inertio-elastic 'ringing' events (i.e. damped oscillations) are observed in the angular displacement measured at the start of a creep test, as a resul...

Objective(s): One applications of nanotechnology is in the area of medicine which is called nanomedicine. Primary instruments in nanomedicine can help us to detect diseases and used for drug delivery to inaccessible areas of human tissues. An important issue in simulating the motion of nanoparticles is modeling blood flow as a Newtonian or non-Newtonian fluid. Sometimes blood flow is simulated ...

Three dimensional flow of non-Newtonian viscoelastic fluid with the variation in the viscosity over a stretching surface is investigated. The governing partial differential equations of continuity, momemtum, energy and concentration are transformed into nonlinear ordinary differential equations by using similarity transformations. The transformed equations are solved numerically by fourth-order...

Abstract. This paper is concerned with the diffusion of a fluid through a viscoelastic solid undergoing large deformations. Using ideas from the classical theory of mixtures and a thermodynamic framework based on the notion of maximization of the rate of entropy production, the constitutive relations for a mixture of a viscoelastic solid and a fluid (specifically Newtonian fluid) are derived. B...

The qualitative effect of nonuniform temperature gradient on the linear stability analysis of the Rayleigh-Benard convection problem in a Boussinesquian, viscoelastic fluid-filled, high-porosity medium is studied numerically using the single-term Galerkin technique. The eigenvalue is obtained for free-free, free-rigid, and rigid-rigid boundary combinations with isothermal temperature conditions...

Our study is motivated by an attempt to develop a rigorous mathematical model of a suspension highly filled with a large number of small solid particles, which interact due to surface forces. We use asymptotic analysis in the small parameter , and consider irregular (nonperiodic) geometries for which the sizes of particles and the distances between them are of order . We present conditions unde...

The Rayleigh-Stokes problem for a generalized Maxwell fluid in a porous half-space with a heated flat plate is investigated. For the description of such a viscoelastic fluid, a fractional calculus approach in the constitutive relationship model is used. By using the Fourier sine transform and the fractional Laplace transform, exact solutions of the velocity and the temperature are obtained. Som...

The dynamics of drop formation and pinch-off have been investigated for a series of low viscosity elastic fluids possessing similar shear viscosities, but differing substantially in elastic properties. On initial approach to the pinch region, the viscoelastic fluids all exhibit the same global necking behaviour that is observed for a Newtonian fluid of equivalent shear viscosity. For these low ...