Dynamics of particle migration in channel flow of viscoelastic fluids
Name
McKinley_Dynamics of particle.pdf
Size
1.3 MB
Format
Adobe PDF
Checksum (MD5)
e2d34f4a5f210688ef2917578d5eb141
Author(s)
Li, Gaojin
McKinley, Gareth H
Ardekani, Arezoo
Date Issued
November 2015
Journal
Journal of Fluid Mechanics
Publisher
Cambridge University Press
Citation
Li, Gaojin, Gareth H. McKinley, and Arezoo M. Ardekani. “Dynamics of Particle Migration in Channel Flow of Viscoelastic Fluids.” Journal of Fluid Mechanics 785 (November 23, 2015): 486–505. doi:10.1017/jfm.2015.619.
Version
Author's final manuscript
Abstract
The migration of a sphere in the pressure-driven channel flow of a viscoelastic fluid is studied numerically. The effects of inertia, elasticity, shear-thinning viscosity, secondary flows and the blockage ratio are considered by conducting fully resolved direct numerical simulations over a wide range of parameters. In a Newtonian fluid in the presence of inertial effects, the particle moves away from the channel centreline. The elastic effects, however, drive the particle towards the channel centreline. The equilibrium position depends on the interplay between the elastic and inertial effects. Particle focusing at the centreline occurs in flows with strong elasticity and weak inertia. Both shear-thinning effects and secondary flows tend to move the particle away from the channel centreline. The effect is more pronounced as inertia and elasticity effects increase. A scaling analysis is used to explain these different effects. Besides the particle migration, particle-induced fluid transport and particle migration during flow start-up are also considered. Inertial effects, shear-thinning behaviour, and secondary flows are all found to enhance the effective fluid transport normal to the flow direction. Due to the oscillation in fluid velocity and strong normal stress differences that develop during flow start-up, the particle has a larger transient migration velocity, which may be potentially used to accelerate the particle focusing.
MIT Department
Massachusetts Institute of Technology. Department of Mechanical Engineering
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1017/jfm.2015.619
