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...

We numerically investigate the effects of non-Newtonian fluid properties, including shear thinning and elasticity, on the locomotion of Taylor’s swimming sheet with arbitrary amplitude. Our results show that elasticity hinders the swimming speed, but a shear-thinning viscosity in the absence of elasticity enhances the speed. The combination of the two effects, modelled using a Giesekus constitu...

A model of the lattice Boltzmann method for non-Newtonian fluids was constructed. The shear stress of purely viscous but non-elastic non-Newtonian fluid is a function of shear rate only. For the power-law model, only two constant parameters can cover shear-thinning and shear-thickening fluids. Two power-law models are introduced to the finite difference lattice Boltzmann method. One is a model ...

The effect of extensional flow on apparent shear viscosity has never previously been directly measured nor is it often considered. Here, for the first time, through using a novel configuration (two-phase response under flow), we have viscoelastic polymer solution in controlled and kinematically mixed manner. We show, via control transient experiment, that deformation depends not only rate but a...

We present special numerical techniques for non-Newtonian flows including non-isothermal, shear/pressure dependent and particularly viscoelastic effects which are based on the logconformation reformulation (LCR), including Oldroyd-B and Giesekus-type fluids as prototypical models. We utilize a fully coupled monolithic finite element approach which treats the velocity, pressure, temperature and ...

Recent experiments have shown that it is possible to self-assemble very uniform polymeric microfibers and nanofibers by exploiting elasto-capillary thinning of macroscopic liquid bridges (Harfenist et al., Nano Lett., 4(10), 2004). We develop a model of this process that describes the simultaneous viscoelasto-capillary thinning and drying of polymeric liquid filaments. A one-dimensional formula...

Rheological characterization of complex fluids subjected to cyclic shear-rate sweep often exhibits hysteresis. Since both viscoelastic and thixotropic materials show hysteresis loops, it is important understand distinguishing features (if any) in the same shown by either. Lately, there has been substantial work that attempts relate area enclosed loop with manner which shear rate varied cycle, o...