Elasto-inertial turbulence (EIT), a new turbulent state found in polymer solutions with viscoelastic properties, is associated drag-reduced turbulence. However, the relationship between EIT and not currently well-understood, it important to elucidate mechanism of transition EIT. The instability fluids has been studied canonical wall-bounded shear flow investigate process In this study, we numer...

Viscoelasticity can dramatically exacerbate free surface flow instabilities. It is shown here that this destabilization arises, at least in part, from the combination of large tangential tension and curvature along a concave free surface. Tension and curvature generically lead to an unstable stress gradient at the free surface; a perturbation that locally thickens a fluid layer leads to a local...

The study aims at quantifying the effect of fluid elasticity on frictional pressure drop for the flow of viscoelastic fluid through a helical coil. Aqueous solutions of polyacrylamide (PAA) in the concentration range 0.25 %–0.5 % (wt/vol.) were used as test fluids. The fluids were characterized using dynamic rheometer under rotational and oscillatory modes. The rheological study depicts that th...

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, ...

Migration of a particle in confined shear flow Giesekus fluids is investigated numerically with the method direct forcing/fictitious domain. We focus on migration direction for initial lateral position y0 and determination critical point yc moving towards center line or wall. The effect viscosity ratio μr, shear-thinning parameter α, Weissenberg number Wi, blocking rate β value analyzed. result...

In this study, we investigate the viscoelasticity-induced migration of solid particles immerged in three-dimensional flow field created by rotation a Rushton turbine. At same time, propose scaling law for predicting characteristic particle time as function Weissenberg number. Particle image velocimetry is adopted to reconstruct velocity and deformation rate fields generated turbine both Newtoni...

In this numerical study, an original approach to simulate non-isothermal viscoelastic fluid flows at high Weissenberg numbers is presented. Stable computations over a wide range of are assured by using the root conformation in finite volume framework on general unstructured meshes. The stabilization extended consider thermo-rheological properties Oldroyd-B type fluids. temperature dependence mo...