While significant progress has been made in the modeling and simulation of uniform fiber suspensions, no existing model has been validated for industrially-relevant concentrated suspensions containing fibers of multiple aspect ratios. In the present work, we investigate bi-disperse suspensions with two fiber populations in varying aspect ratios in a steady shear flow using direct numerical simulations. Moreover, we measure the suspension viscosity by creating a controlled length bidispersity for nylon fibers suspended in a Newtonian fluid. Here the results showed good agreement between the experimentally measured and numerically predicted viscosity for bi-disperse suspensions. The ratio between the aspect ratio of large to small fibers (size ratio) and the volume fraction of large fibers (composition) in bi-disperse systems strongly affected the rheological behavior of the suspension. The increment of relative viscosity associated with size ratio and composition can be explained by the decrease in the maximum flowable limit or jamming volume fraction. Moreover, the relative viscosity of bi-disperse suspensions collapses, when plotted against the reduced volume fraction, demonstrating the controlling influence of the jamming fraction in bi-disperse fiber suspensions.
Khan, Monsurul, Corder, Ria D., Erk, Kendra A., & Ardekani, Arezoo M. (2024). Rheology of bi-disperse dense fiber suspensions. Soft Matter, 20(4). https://doi.org/10.1039/d3sm00787a
Khan, Monsurul, Corder, Ria D., Erk, Kendra A., et al., "Rheology of bi-disperse dense fiber suspensions," Soft Matter 20, no. 4 (2024), https://doi.org/10.1039/d3sm00787a
@article{osti_2283643,
author = {Khan, Monsurul and Corder, Ria D. and Erk, Kendra A. and Ardekani, Arezoo M.},
title = {Rheology of bi-disperse dense fiber suspensions},
annote = {While significant progress has been made in the modeling and simulation of uniform fiber suspensions, no existing model has been validated for industrially-relevant concentrated suspensions containing fibers of multiple aspect ratios. In the present work, we investigate bi-disperse suspensions with two fiber populations in varying aspect ratios in a steady shear flow using direct numerical simulations. Moreover, we measure the suspension viscosity by creating a controlled length bidispersity for nylon fibers suspended in a Newtonian fluid. Here the results showed good agreement between the experimentally measured and numerically predicted viscosity for bi-disperse suspensions. The ratio between the aspect ratio of large to small fibers (size ratio) and the volume fraction of large fibers (composition) in bi-disperse systems strongly affected the rheological behavior of the suspension. The increment of relative viscosity associated with size ratio and composition can be explained by the decrease in the maximum flowable limit or jamming volume fraction. Moreover, the relative viscosity of bi-disperse suspensions collapses, when plotted against the reduced volume fraction, demonstrating the controlling influence of the jamming fraction in bi-disperse fiber suspensions.},
doi = {10.1039/d3sm00787a},
url = {https://www.osti.gov/biblio/2283643},
journal = {Soft Matter},
issn = {ISSN 1744-683X},
number = {4},
volume = {20},
place = {United States},
publisher = {Royal Society of Chemistry},
year = {2024},
month = {01}}
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 367, Issue 1909https://doi.org/10.1098/rsta.2009.0194