The transition to irreversibility in sheared suspensions: An analysis based on a mesoscopic entropy production

TL;DR

This paper investigates the transition to irreversibility in sheared suspensions by analyzing entropy production, revealing thermodynamic mechanisms and scaling behaviors through simulations and theoretical insights.

Contribution

It provides a thermodynamic explanation of the irreversibility transition in suspensions using entropy production analysis and simulation data.

Findings

Entropy production coupling explains displacement scaling.

Shear-induced diffusion depends on volume fraction.

Simulations show the effect across different Reynolds numbers.

Abstract

We study the shear-induced diffusion effect and the transition to irreversibility in suspensions under oscillatory shear flow by performing an analysis of the entropy production associated to the motion of the particles. We show that the Onsager coupling between different contributions to the entropy production is responsible for the scaling of the mean square displacement on particle diameter and applied strain. We also show that the shear-induced effective diffusion coefficient depends on the volume fraction and use Lattice-Boltzmann simulations to characterize the effect through the power spectrum of particle positions for different Reynolds numbers and volume fractions. Our study gives a thermodynamic explanation of the the transition to irreversibility through a pertinent analysis of the second law of thermodynamics.