Paper Number
GG9 

Session
Rheology of Gels, Glasses and Jammed Systems

Title
Dynamics of the stress distributions of jammed suspensions of soft particle glasses in startup and oscillatory shear flows

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

Track / Room
Track 3 / Sheraton 5

Authors (Click on name to view author profile)

1. Bantawa, Minaspi (University of Texas at Austin, Department of Chemical Engineering)
2. Bonnecaze, Roger T. (University of Texas at Austin, Department of Chemical Engineering)

Author and Affiliation Lines (in printed abstract book)
Minaspi Bantawa and Roger T. Bonnecaze
Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712

Speaker / Presenter 
Bantawa, Minaspi

Keywords
colloids; glasses; jammed systems; suspensions

Text of Abstract
The jammed suspensions of soft particle glasses (SPGs) exhibit interesting rheological response under start-up and oscillatory shear flows. Macroscopic measurements indicate SPGs “remember” their past history. We hypothesize that the rheology of SPGs is sensitive to the applied shear rate and shear history which manifest in the different microscopic rearrangements of individual particles and their contribution to the total stress. Using large scale 3D numerical simulations of model SPGs, we show that shear induced microstructural rearrangements at different points in the stress-strain curve result in distinct distributions of local stresses, which impact the overall rheological response. Interestingly, suspensions with the same microscopic stress can have very different distributions of stress locally. Although distributions of stresses vary locally, long-ranged correlations are not observed. We demonstrate the correspondence between components of the pair correlation function and shear and normal stress differences. We propose a reduced order model of the evolution of the microstructure to predict the rheological response in transient and unsteady flows.