Paper Number
DP22                         My Program 

Session
Dense Particulate Systems

Title
Dynamic thickening and dethickening of 3D dense suspensions of Quincke rotors

Presentation Date and Time
October 15, 2024 (Tuesday) 2:50

Track / Room
Track 3 / Waterloo 5

Authors (Click on name to view author profile)

  1. Singh, Navneet (Cornell University, Physics)
  2. Barth, Anna R. (Cornell University, Physics)
  3. Ong, Edward Y. (Cornell University, Applied Engineering and Physics)
  4. Shetty, Abhishek (Anton Paar, Rheology)
  5. Chakraborty, Bulbul (Brandeis University, Physics)
  6. Sethna, James P. (Cornell University, Physics)
  7. Dufresne, Eric R. (Cornell University, Physics)
  8. Cohen, Itai (Cornell University, Physics)

Author and Affiliation Lines (in printed abstract book)
Navneet Singh1, Anna R. Barth1, Edward Y. Ong2, Abhishek Shetty3, Bulbul Chakraborty4, James P. Sethna1, Eric R. Dufresne1 and Itai Cohen1
1Physics, Cornell University, Ithaca, NY 14853; 2Applied Engineering and Physics, Cornell University, Ithaca, NY 14853; 3Rheology, Anton Paar, Ashland, VA 23005; 4Physics, Brandeis University, Waltham, MA 02453

Speaker / Presenter 
Singh, Navneet

Keywords
experimental methods; active systems; dense systems

Text of Abstract
Exploring the promising potential of synthetic active materials involves manipulating their macroscopic bulk properties through precise control of microscopic interactions among constituents. While past studies have been constrained by limitations in manufacturing scalability and the capacity to induce significant stresses, hindering investigations into 3D bulk properties, we present imaging and rheological findings on dense suspensions of Quincke rotors that circumvent these barriers. Our experiments unveil that in the absence of shear, Quincke rotation activity gives rise to dynamically evolving percolating structures. Additionally, our experiments reveal an emergent viscosity that is controlled by both suspension volume fraction and the degree of Quincke rotation activity. Strikingly, we find that the system exhibits both dynamic thickening and dethickening, contingent upon the ratio of active stress to shear stress.