View abstract at https://physics.qc.cuny.edu/uploads/colloquia/Jianbo_Liu_F2025.pdf

Using an established simulation technique [1] and motivated by recent work [2] showing the rapid onset of system-spanning rigid structures (identified by a pebble game algorithm) with increase of volume fraction in a highly-concentrated (or dense) suspension, we show that the number of contacts in the network is an increasing function of imposed shear stress, but it also fluctuates during flow.  The microscopic interactions between particles and the general behavior of this shear-thickening suspension will be outlined briefly to provide insight to the network development leading to the changes in rheological properties. 
 
We will then explore, or two-dimensional suspensions (monolayers) the development of minimally rigid structures in the shear-thickened suspension as it approaches jamming at high stress, and show that the onset of large rigid clusters exhibits critical behavior.  The extension to 3D and the possible relationship of this behavior to other work showing critical scaling at the onset of shear thickening and jamming will be discussed.
 

1. R. Mari, R. Seto, J. F. Morris & M. M. Denn 2014 Shear thickening, frictionless and frictional rheologies. J. Rheol. 58, 1693.
2. M. van der Naald, A. Singh, T.T. Eid, K. Tang, J. J. de Pablo & H. M. Jaeger, H.M. 2024. Minimally rigid clusters in dense suspension flow. Nature Physics 20, 653–659.