Linear and non-linear viscoelasticity, relaxation behavior steady shear viscosity of polylactide (PLA) nanocomposites filled with 1.5–9 wt.% graphene nanoplatelets (GNPs) multiwall carbon nanotubes (MWCNTs) are studied to gain control on printability. Results show strongly increased rheological characteristics, good dispersion, small fractal size very low percolation threshold MWCNTs in PLA, li...

Research interest in nanotechnology is growing due to its diversified engineering and medical applications. Due the importance of bioconvection biotechnology various biological systems, scientists have made significant contributions last ten years. The present study focusing on investigation magnetohydrodynamics (MHD) bioconvective heat transfer a Williamson nanofluid past an inclined moving pl...

The friction factor and heat transfer of Giesekus-fluid-based nanofluids in a pipe flow were studied the ranges 0.5 ≤ Reynolds number (Re) 500, 1 Weissenberg (Wi) 8, 0.5% particle volume concentration (Φ) 3.0%, 0 viscosity ratio (β0) 1, mobility parameter (α) 0.5. Our numerical method was validated by comparing results with available ones literature. effects Wi, Φ, β0, Re, α on relative (Cf/CfN...

This study is devoted to the analysis of physical meaning difference in results viscosity measurements obtained by using two-capillary method—carrying on same flow rate through two circular parallel capillaries different lengths but diameter. Furthermore, there other approach for short determination a value, known as “elongational viscosity,” based concept domination extension at convergent alo...

In this work, we use flow visualization and rheometry techniques to study the dynamics and evolution of secondary flows in a model wormlike micellar solution sheared between concentric cylinders, i.e., in a Taylor-Couette (TC) cell. The wormlike micellar solution studied in this work contains cetyltrimethylammonium bromide (CTAB) and sodium salicylate (NaSal). This system can be shear banding a...

The crystal structure of the potassium salt of 2,2,5,5-tetramethyl-3-carboxypyrroline-1-oxyl (I), which is a free radical of the nitroxide type, has been determined by three-dimensional X-ray methods. The unit cell contains two crystallographically different types of molecule, one of which lies with its five-membered ring entirely in a mirror plane and is therefore perfectly flat. Molecules of ...

The non-linear dynamics of a semi-dilute (c/c* = 15) polydisperse polyethylene oxide (PEO) solution in microfluidics are studied experimentally using benchmark contraction–expansion flow geometries with three contraction–expansion ratios (4:1:4, 8:1:8 and 16:1:16) and two narrow channel lengths (Lc/Dh = 53 and 5.3, where Lc is the length of the narrow channel and Dh is its hydraulic diameter). ...

We investigate the transient, fluid–structure interaction (FSI) of a non-Newtonian fluid peeling two Hookean sheets at low Reynolds numbers ( R e ≪ 1 ). Two different fluids are considered – simplified Phan–Thien–Tanner (sPTT) model fluid, and an inelastic with shear-thinning viscosity (generalized Newtonian fluid). In limit small gap between sheets, we invoke lubrication approximation numerica...

This paper is an pedagogical essay on the scenario of the instabilities and the transition to turbulence in visco-elastic polymer flows. When polymers are long, they get easily stretched by the shear present in flows, and the viscosity of the solution or melt is large. As a result, inertial effects are usually negligible as the Reynolds numbers are small but the fluid is strongly nonNewtonian d...