Previous experimental measurements and linear stability analyses of curvilinear shearing flows of viscoelastic fluids have shown that the combination of streamwise curvature and elastic normal stresses can lead to flow destabilization. Torsional shear flows of highly elastic fluids with closed streamlines can also accumulate heat from viscous dissipation resulting in nonuniformity in the temper...

in this paper, the combined effect of suspended (fine dust) particles and rotation on the onset of thermosolutal convection in an elastico-viscous fluid in a porous medium is studied. for the porous medium, the brinkman model is employed and rivlin-ericksen model is used to characterize viscoelastic fluid. by applying normal mode analysis method, the dispersion relation has been derived and sol...

In his renowned lecture on Life at low Reynolds number, E.M. Purcell established that a rigid swimmer comprised of two links cannot swim in a viscous Newtonian fluid due to the reciprocal nature of its movements. Viscoelastic fluid, on the other hand, has a characteristic time scale associated with stress relaxation and can impart asymmetrical stresses on the body of a swimmer to propel it forw...

Transverse ridges are regions of anomalously high uplift that, run parallel to many of the transform fattits at mid-ocean ridges. Previous models of the formation of these ridges generally fail to explain the magnitude of uphft (between 1 and 8 km) or account for geophysical observations (which indicate that the ridges are dynamically uphfted by neutral or heavy, but not buoyant, material). How...

– The viscoelastic effect on the hydrodynamic relaxation in semi-dilute polymer solutions is investigated. From the linearized two-fluid model equations we predict that the dynamical asymmetry coupling between the velocity fluctuations and the viscoelastic stress influences on the hydrodynamic relaxation process, resulting in a wave number dependent shear viscosity. Previously, Doi and Onuki [1...

We investigate the transient viscoelastic behavior of weakly strain-hardening fluids in filament stretching devices during uniaxial elongation and following the cessation of stretching. The numerical results are compared with experimental observations on a concentrated shear-thinning polystyrene solution which is well characterized by a multi-mode Giesekus model. The finite element computations...

It is demonstrated that an AT-cut quartz crystal driven in the thickness-shear-wave mode and typically used as a sensor to monitor the viscoelastic shear-wave properties of a fluid also produce longitudinal pressure waves. Unlike the shear wave, these waves are capable of long-range propagation through the fluid and of reflection at its boundaries, notably at an outer fluid–air interface. They ...

A thermal colloid suspended in a liquid will transition from a short-time ballistic motion to a long-time diffusive motion. However, the transition between ballistic and diffusive motion is highly dependent on the properties and structure of the particular liquid. We directly observe a free floating tracer particle's ballistic motion and its transition to the long-time regime in both a Newtonia...

In this article we analyse a fully discrete approximation to the time dependent viscoelasticity equations allowing for multicomponent fluid flow. The Oldroyd B constitutive equation is used to model the viscoelastic stress. For the discretization, time derivatives are replaced by backward difference quotients, and the non-linear terms are linearized by lagging appropriate factors. The modeling ...

The eukaryotic cell nucleus harbours the DNA genome that is organized in a dynamic chromatin network and embedded in a viscous crowded fluid. This environment directly affects enzymatic reactions and target search processes that access the DNA sequence information. However, its physical properties as a reaction medium are poorly understood. Here, we exploit mobility measurements of differently ...