An analysis has been carried out to obtain the free convective heat and mass transfer characteristics of an incompressible MHD viscoelastic fluid flow immersed in a porous medium of variable permeability bounded by an infinite porous vertical plate in slip flow regime in the presence of a transverse magnetic field with heat source and radiation effects. The permeability of the porous medium dec...

In this study, we present experimental results on particle-wall collision in viscoelastic fluids. A sphere is released in a tank filled with poly(ethylene-oxide) (PEO) mixed with water with varying concentrations up to 1.5%. The effect of Stokes and Deborah numbers on the rebound velocity of a spherical particle colliding onto a wall is considered. It has been observed that the slope at which t...

In this work, particle-wall interaction in viscoelastic fluids is experimentally studied. The effect of Stokes number, Weissenberg number and surface roughness on the rebound velocity of a colliding spherical particle on a wall is considered. Different steel spherical particles are released in viscoelastic solutions of different high-molecular-weight polymers in water with different concentrati...

This paper presents a new and efficient method for computing the flow of a non-Newtonian fluid. The approach is based on two independent concepts: Time-dependent simulation of viscoelastic flow: A new decoupled algorithm, presented in P. Saramito, Simulation numerique d'ecoulements de fluides viscoelastiques par eRments finis incompressibles et une methode de directions alternees; applications,...

This article addresses the low Weissenberg asymptotic analysis (Newtonian limit) of some macroscopic models of viscoelastic fluid flows in the framework of global weak solutions. We investigate the convergence of the corotational Johnson-Segalman, the FENE-P, the Giesekus and PTT models. Relying on a priori bounds coming from energy or free energy estimates, we first study the weak convergence ...

Peristaltic motion of viscoelastic incompressible fluid in an axisymmetric tube with a sinusoidal wave is studied theoretically in the case that the radius of the tube is small relative to the wavelength. Oldroyd flow has been considered in this study and the problem is formulated and analyzed using a perturbation expansion in terms of the variation of the wave number. This analysis can model t...

In our study of the aging phenomena in silica suspensions we immersed precipitated silica particles in methyl-terminated PDMS (silicone oil), mineral oil, and glycerol/water and measured their viscoelastic properties as a function of time. We found that the samples based on silicone oil, initially of a pasty consistence, became fluid-like after a period of about three weeks. Aqueous samples age...

A mathematical model describing the constitutive properties of biofilms is required for predicting biofilm deformation, failure, and detachment in response to mechanical forces. Laboratory observations indicate that biofilms are viscoelastic materials. Likewise, current knowledge of biofilm internal structure suggests modeling biofilms as associated polymer viscoelastic systems. Supporting expe...

In this paper, we present an analytical method for solving a well-posed boundary value problem of mathematical physics governing the vibration characteristics of an internal flow propelled fluid-structure interaction where the pipeline segment is idealized as an elastic hollow beam conveying an incompressible fluid on a viscoelastic foundation. The effect of Coriolis and damping forces on the o...

Potential flows of incompressible fluids admit a pressure (Bernoulli) equation when the divergence of the stress is a gradient as in inviscid fluids, viscous fluids, linear viscoelastic fluids and second-order fluids. We show that the equation balancing drag and acceleration is the same for all these fluids independent of the viscosity or any viscoelastic parameter and that the drag is zero in ...