Paper Number
SC24
Session
Suspensions, Colloids, and Granular Materials
Title
Spherically confined Brownian suspensions: Influence of locally heterogenous structure on diffusion and rheology
Presentation Date and Time
October 13, 2021 (Wednesday) 9:50
Track / Room
Track 5 / Ballroom 6
Authors
- Sunol, Alp M. (Stanford University, Department of Chemical Engineering)
- Zia, Roseanna N. (Stanford University, Department of Chemical Engineering)
Author and Affiliation Lines
Alp M. Sunol and Roseanna N. Zia
Department of Chemical Engineering, Stanford University, Stanford, CA 94305
Speaker / Presenter
Sunol, Alp M.
Keywords
computational methods; colloids; confined flows; suspensions
Text of Abstract
Spherically confined, hydrodynamically interacting colloids provide a framework for understanding biological cells over length and time scales where interparticle interactions and particle motion play central and nontrivial roles in whole-cell behavior. Under different biological conditions, a cell’s overall size, crowding level, and the strength of electrostatic interactions of its constituent molecules can change. Therefore, it is important to understand how each of these changes alters the physics of biological processes that take place inside cells. In this work, we perform dynamic simulations with both Confined Stokesian Dynamics and Confined Brownian Dynamics algorithms. Confinement induces new and disparate length and time scales of colloidal relaxation on a suspension, which results in a heterogeneous microstructure and local crowding. This structure in turn impacts dynamics and rheology both entropically and hydrodynamically. We disentangle the role of entropic and hydrodynamic effects on short- and long-time transport properties of particles under spherical confinement to better understand differences between real life systems under conditions of weak and strong hydrodynamics. Additionally, we find relationships between rheological properties, such as osmotic pressure and viscosity, and the variables volume fraction and particle size within the confinement.