Paper Number
SC49 

Session
Suspensions and Colloids

Title
Hydrodynamic coupling to the electrical response of fluid suspensions of non-Brownian conducting particles

Presentation Date and Time
October 12, 2022 (Wednesday) 4:05

Track / Room
Track 1 / Sheraton 4

Authors (Click on name to view author profile)

  1. Lin, Han (Northwestern University, Chemical and Biological Engineering)
  2. Majji, Madhu V (Massachusetts Institute of Technology, Department of Chemical Engineering)
  3. Cho, Noah (Northwestern University, Chemical and Biological Engineering)
  4. Zeeman, John R. (Northwestern University, Chemical and Biological Engineering)
  5. Swan, James W. (Massachusetts Institute of Technology, Chemical Engineering)
  6. Richards, Jeffrey J. (Northwestern University, Chemical and biological engineering)

Author and Affiliation Lines (in printed abstract book)
Han Lin1, Madhu V Majji2, Noah Cho1, John R. Zeeman1, James W. Swan2 and Jeffrey J. Richards1
1Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208; 2Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139

Speaker / Presenter 
Richards, Jeffrey J.

Keywords
experimental methods; computational methods; rheometry techniques; suspensions

Text of Abstract
We report on the electrical response of suspensions of non-Brownian, conductive particles subjected to shear flow. We find a strong shear rate and volume fraction dependence to the electrical conductivity. We quantify this dependence be determining the electrical diffusivity using chronoamperometry and impedance spectroscopy. We demonstrate collapse of the electrical diffusivity with an empirical scaling law that quantitatively predicts that rate of charge transport. Finally, we perform Stokesian dynamics simulations coupled with a kinetic Monte Carlo scheme to interrogate the microscopic origin of the transport process and demonstrate not only quantitative agreement with experimental data but show that the electrical diffusivity exceeds the self-diffusivity of the particles. We conclude that electrical transport in non-Brownian suspensions is dominated by the shear driven dynamical interactions within these suspensions that facilitate electron delocalization over dynamic clusters that form along the flow compressional axis.