Related Experiment Video
Updated: Mar 14, 2026

Flexural Rigidity Measurements of Biopolymers Using Gliding Assays
Published on: November 9, 2012
Torsional stiffness determines aggregate structure in sheared colloidal rod suspensions
Justin T Stimatze1, David A Egolf1, Jeffrey S Urbach1
1Department of Physics and Institute for Soft Matter Synthesis and Metrology, Georgetown University, Washington, DC, USA. urbachj@georgetown.edu.
Abstract:
We report the results of simulations of suspensions of sheared rigid rods in the presence of strong attractive inter-particle interactions, using dissipative particle dynamics for a coarse-grained representation of the suspending fluid. We find that the combined effect of the attractive interactions and shear-induced alignment generically produces aggregates of aligned bundles when the contact points between rods are free to rotate. However, the introduction of substantial torsional stiffness to the inter-particle contacts recapitulates the disordered aggregates often observed in suspensions of high aspect ratio particles. We show that the degree of alignment within the aggregates depends on the strength of the torsional stiffness, while the stability of the aggregates and their impact on system viscosity depend on the competition between the attractive interaction and the shear stresses.
Related Concept Videos
Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
Circular Shaft - Stresses in Linear Range
Torsion of Noncircular Members
Stability of structures
Shearing Strain
Elastic Strain Energy for Shearing Stresses

