Comparison of compression versus shearing near jamming, for a simple model of athermal frictionless disks in suspension

Using a simplified model for a non-Brownian suspension, we numerically study the response of athermal, overdamped, frictionless disks in two dimensions to isotropic and uniaxial compression, as well as to pure and simple shearing, all at finite constant strain rates (epsilon) over dot. We show that isotropic and uniaxial compression result in the same jamming packing fraction phi(J), while pure-shear-and simple-shear-induced jamming occurs at a slightly higher phi(J)*, consistent with that found previously for simple shearing. A critical scaling analysis of pure shearing gives critical exponents consistent with those previously found for both isotropic compression and simple shearing. Using orientational order parameters for contact bond directions, we compare the anisotropy of the force and contact networks at both lowest nematic order, as well as higher 2n-fold order.

Automated summary

Using a simplified model, this study examines the response of non-Brownian suspension in two dimensions to compression and shear. It shows that compression and shear induce jamming at different packing fractions. Furthermore, a critical analysis reveals consistent scaling behavior among compression, shear, and pure shearing. The study also investigates the anisotropy of force and contact networks using orientational order parameters.