Numerical flow simulation is useful for understanding fluid phenomena such as blood flow or pulse wave propagation in the systemic arteries. For numerical analysis of intravascular flow, it is important to consider not only incompressible assumption and blood viscosity but also the viscoelasticity of the blood vessel wall; however, blood flow in vivo is complicated because of the unsteadiness o...

the main objective of the present work was to synthesis polyamide 6 through anionic polymerization of ε-caprolactam in an internal mixer. the reaction time and the rheological properties of samples during the polymerization were studied. the samples were characterized by thermo gravimetry analysis (tga), differential scanning calorimeter (dsc) and ft-ir spectrometer. the melt flow behavior and ...

This study is concerned with the investigation of the associated properties of subcell discretisations for viscoelastic flows, where aspects of compatibility of solution function spaces are paramount. We introduce one new scheme, through a subcell finite element approximation fe(sc), and compare and contrast this against two precursor schemes – one with finite element discretisation in common, ...

Partially liquefied vitreous humor is a common physical and biochemical degenerative change in vitreous body which the liquid component gets separated from collagen fiber network and leads to form a region of liquefaction. The main objective of this research is to investigate how the oscillatory motions influence flow dynamics of partial vitreous liquefaction (PVL). So far computational fluid d...

We investigate the flow patterns of Newtonian and viscoelastic fluids in microchannels containing bifurcations. The Newtonian fluid used as a reference is de-ionized water, while the non-Newtonian fluid used in the experiments has a shear rheology similar to that of human blood. The geometrical shape of the channels used reproduce bifurcating vessels, typically encountered in microcirculation n...

The viscoelastic properties of nine silicone-, polysulfide-, and polyether-based impression materials were determined using creep tests. During deformation the materials demonstrated linear viscoelastic behavior. The creep compliance curves, recovery, and percent set were calculated. Permanent deformation in these materials is a result of lack of recovery of elastic deformation as well as visco...

One of the newest of viscoelastic RANS turbulence models for drag reducing channel flow with polymer additives is studied in different flow and rheological properties. In this model, finitely extensible nonlinear elastic-Peterlin (FENE-P) constitutive model is used to describe the viscoelastic effect of polymer solution and turbulence model is developed in the k-ϵ-(ν^2 ) ̅-f framework. The geome...

We developed a new lattice Boltzmann method that allows the simulation of two-phase flow of viscoelastic liquid mixtures. We used this new method to simulate a bubble rising in a viscoelastic fluid and were able to reproduce the experimentally observed cusp at the trailing end of the bubble.  2000 Elsevier Science B.V. All rights reserved.

We exploited the viscoelasticity of biocompatible dilute polymeric solutions, namely, dilute poly(ethylene oxide) solutions, to significantly enhance mixing in microfluidic devices at a very small Reynolds number, i.e., Re approximately 0.023, but large Peclet and elasticity numbers. With an abrupt contraction microgeometry (8:1 contraction ratio), two different dilute poly(ethylene oxide) solu...

We have studied the rheological properties of mixtures of polyoxyethylene (10 mol) phytosterol (PhyEO(10)) and polyoxyethylene (10 mol) cholesterol (ChEO(10)) mixed in different ratios along with tetraethylene glycol monododecyl ether (C(12)EO(4)) surfactants in water. Addition of C(12)EO(4) to the aqueous solution of a mixture of (PhyEO(10) + ChEO(10)) results in one-dimensional micellar growt...