Effect of a porous layer on Newtonian and power-law fluids flows between rotating cylinders using lattice Boltzmann method

Khali, Samir; Nebbali, Rachid; Bouhadef, Khedidja

doi:10.1007/s40430-017-0809-6

Cited by 10 publications

(5 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several researchers have addressed the effect of shear-thinning on the critical Reynolds number for the formation of Taylor vortices, predicting a decrease in Re c with increased shear-thinning for large values of η (i.e. when curvature effects are small) (Coronado-Matutti, Souza Mendes & Carvalho 2004;Caton 2006;Ashrafi 2011), which has been supported by various numerical and experimental studies (Lockett, Richardson & Worraker 1992;Khali, Nebbali & Bouhadef 2013;Cagney & Balabani 2019b). Bahrani et al (2015) found that for a very large gap, η = 0.4, shear-thinning led to an increase in the wavelength of Taylor vortex flow (i.e.…”

Section: Introductionmentioning

confidence: 82%

Taylor–Couette flow of polymer solutions with shear-thinning and viscoelastic rheology

2020

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 82%

Taylor–Couette flow of polymer solutions with shear-thinning and viscoelastic rheology

2020

View full text Add to dashboard Cite

show abstract

“…As any numerical simulation, a convergence criterion of our L.B.M. code is adopted to stop the computational process when the following convergence criterion is satisfied as reported in Khali et al (2017):…”

Section: Numerical Resultsmentioning

confidence: 99%

“…At the bottom of the duct, the boundary condition for the concentration field is: Khali et al (2017) ( )…”

Section: Boundary Conditionsmentioning

confidence: 99%

Numerical Study of the Effect of a Power-law Fluid Flow Structures on Levels of Mixing in a Taylor Couette Configuration

2023

JAFM

View full text Add to dashboard Cite

This work is a numerical study on the effects of the flow structures of the power-law fluid between two concentric cylinders with an upward laminar axial flow on levels of mixing and mean residence time through the Taylor Couette system. The cylindrical annular duct presents a radius ratio of 0.5 and an aspect ratio of 8. The inner cylinder is rotating while the outer one is kept at rest. The residence time distributions (R.T.D.) method and the mean residence time (Tm) are used to determine the number of tanks in series and the dispersion coefficient to evaluate levels of mixing. To this end, a pulsed input injection of a tracer is computing at the outlet of the annulus. As a main objective of this study, is to analyze the effect of the flow structure of a power-law fluid between two concentric cylinders on the mixing level and mean residence time in a Taylor Couette system. The novelty of our work is the use of power-law fluids as particles-carrying fluids. Several parameters, such as the axial Reynolds number (Re), the Taylor number (Ta), and the power-law index behavior (n), are used to show their impact on levels of mixing. It is shown that when n increases, the number of stirred tanks in series N increases for pseudoplastic fluids (n<1), indicating low levels of mixing while the parameter (N) decreases for dilatants fluids (n>1), revealing high levels of mixing. The increase of the power-law index in the range of 0.6<n<1 decreases the dispersion coefficient, indicating the non-ideal mixing in the duct. In addition, for further increase of the power-law index in the range of n>1 increases the dispersion coefficient points to the well-mixing.

show abstract

“…The study of Taylor-Couette flow was mainly initiated by Taylor [14] for standard Newtonian fluids and has been the focus of considerable attention until now. The numerical predictions by Lockett et al [15], Khali et al [16], Alibenyahia et al [11], and Ashrafi [9] reported that the shear thinning characteristics of the working fluid affect the mode transition of the flow and that the resultant critical Reynolds number becomes lower. By using a deterministic approach to analyze the nonlinear flow stability, the related results demonstrated that the dynamics of flow transition are completely different in Taylor-Couette flow with Newtonian working fluids and are caused by the shear thinning properties of the fluid.…”

Section: Flow In Rotating Cylindersmentioning

confidence: 99%

Experimental Studies on the Taylor-Couette Flow of Shear-Thinning Fluids

Kawaguchi¹

2022

GEOMATE

View full text Add to dashboard Cite

Two concentric cylinders with the inner cylinder rotating cause circumferential flow with a Taylor vortex under a certain range of Reynolds numbers. This is called Taylor-Couette flow. It has been the focus of extensive study in terms of Newtonian fluids but not non-Newtonian fluids. Despite various industrial applications, the flow transition mechanism of the flow remains unclear. Therefore, many kinds of apparatuses using Taylor-Couette flow in the redesign and scale-up are still under investigation. The objective of the present study is first to determine the transition points of Taylor-vortex flow and the wavy vortex flow regime with a non-Newtonian working fluid. To understand the effect of the working fluid, two kinds of shear-thinning liquids with different structural viscosity indices were compared. Particle image velocimetry (PIV) was used as the flow visualization technique for a wide range of Reynolds numbers. A water solution of guar gum resulted in a stable six-cell mode in the Taylor-vortex flow and wavy-vortex flow regimes. The other working fluid, with xanthan gum, resulted in a vertically enlarged oval vortex that appeared under the same Reynolds number range. Both results were significantly different from the flow with Newtonian working fluid. In conclusion, we confirm that the shear-thinning characteristics of the working fluid affect the aspect ratio of the edge vortex as well as the drifting of the vortex center along the axis of the cylinder.

show abstract

Effect of a porous layer on Newtonian and power-law fluids flows between rotating cylinders using lattice Boltzmann method

Cited by 10 publications

References 23 publications

Taylor–Couette flow of polymer solutions with shear-thinning and viscoelastic rheology

Taylor–Couette flow of polymer solutions with shear-thinning and viscoelastic rheology

Numerical Study of the Effect of a Power-law Fluid Flow Structures on Levels of Mixing in a Taylor Couette Configuration

Experimental Studies on the Taylor-Couette Flow of Shear-Thinning Fluids

Contact Info

Product

Resources

About