Implementation note on a minimal hybrid lubrication/granular dynamics model for dense suspensions

Abstract

We describe and summarize a class of minimal numerical models emerged from recent development of simulation methods for dense particle suspensions in overdamped linear flows. The main ingredients include (i) a frame-invariant, short-range lubrication model for spherical particles, and (ii) a soft-core, stick/slide frictional contact model activated when particles overlap. We implement a version of the model using a modified velocity-Verlet algorithm that explicitly solves the N -body dynamical system in O(cN ) operations, where c is a kernel constant depending on the cutoff of particle interactions. The implementation is validated against literature results on jamming transition and shear thickening suspensions from 40% to 64% volume fractions. Potential strategies to extend the present methodology to non-spherical particles are also suggested for very concentrated suspensions.

Weakly adhesive suspension shows rate-dependence in oscillatory but not steady shear flows

“…Simulations.-To investigate the anomalous frequency dependence, we use a minimal numerical model based on the hybrid lubrication/granular dynamics [9,20,21]. In this framework, particle dynamics are obtained by approximating the hydrodynamics with near-neighbour lubrication force, combined with interparticle physiochemical or contact interactions.…”

A fast and efficient tool to study the rheology of dense suspensions

“…First, the models of the contributions adopted to simulate the particle-particle and the particle-flow interactions have been presented. The models mimic the ones already available in the literature, echoing in particular the implementation of Mari et al 23 and Ge et al 26,27 .…”

“…Following the work by Ge et al 26,27 , the governing equations (1) are advanced in time with the modified velocity-Verlet scheme 28 ,…”

Irreversibility and rate dependence in sheared adhesive suspensions

“…Discrete element simulations based on a minimal hydrodynamic model are performed for suspensions at zero Reynolds number [22]. Specifically, our model determines particle nonaffine trajectories according to lubrication, contact (hard-sphere) and interparticle potentials, similarly to the Stokesian dynamics [23].…”

“…3. The budget terms correspond to the Stokes (stk), lubrication (lub), contact (ctt) and vdW forces extracted from the simulations [22]. Surprisingly, at φ = 40%, where the maximum vdW effect is expected, virtually no contributions from the attractive vdW forces are visible across three decades of Sr.…”