Paper Number
SC10 

Session
Suspensions and Colloids

Title
Discontinuous shear thickening for bidisperse frictional suspensions

Presentation Date and Time
October 10, 2022 (Monday) 2:30

Track / Room
Track 1 / Sheraton 4

Authors (Click on name to view author profile)

  1. Singh, Abhinendra (The University of Chicago)
  2. Sharma, Abhinendra K. (University of Chicago, Pritzker School of Molecular Engineering)
  3. de Pablo, Juan J. (The University of Chicago, Pritzker School of Molecular Engineering)
  4. Jaeger, Heinrich M. (The University of Chicago, Department of Physics)

Author and Affiliation Lines (in printed abstract book)
Abhinendra Singh1, Abhinendra K. Sharma1, Juan J. de Pablo1 and Heinrich M. Jaeger2
1Pritzker School of Molecular Engineering, The University of Chicago, Chicago, IL 60637; 2Department of Physics, The University of Chicago, Chicago, IL 60637

Speaker / Presenter 
Singh, Abhinendra

Keywords
theoretical methods; computational methods; colloids; jammed systems; suspensions

Text of Abstract
The mechanism of shear thickening in dense suspensions has been linked to a stress-controlled transition from a lubricated "frictionless'' to an unlubricated "frictional'' rheology. Recent particle simulations that constrain the relative motion between particles have been successful to reproduce both the discontinuous shear thickening (DST) and shear jamming (SJ) observed experimentally for rough and smooth particles. However, so far only monodisperse or weakly bidisperse cases are considered. We perform numerical simulations at a fixed volume fraction varying the size ratio of particle radii (up to 1:6) and volume ratio of small particles. We find that at a constant volume fraction, the critical shear stress and frictional viscosity can be tuned through the size ratio and volume ratio of small particles. Contrary to the case of monodisperse systems, viscosity cannot be expressed in terms of the number of frictional contacts. In this presentation, we will investigate these bidisperse systems' network characteristics and microstructure to disentangle the contribution of various types of contacts to the simulated rheology suspensions.