Flow equations for dense granular fluids: New insight from a first-principles derivation

TL;DR

This paper develops a first-principles theoretical framework for dense granular flows, deriving a new relation between stress and strain rate that enhances understanding of flow dynamics and rotational effects.

Contribution

It introduces a novel, first-principles derivation of the stress-strain relation in dense granular flows, challenging existing empirical models.

Findings

Derived a new explicit relation between stress and strain rate tensors.

Revealed the impact of rigid-like rotational regions on flow behavior.

Provided a theoretical basis for plug-free dense granular flow modeling.

Abstract

We present a first-principles theory for plug-free dense granular flow. This is done by coarse-graining directly the microscopic dynamics and deriving an explicit relation between the macroscopic stress and strain rate tensors. The newly derived relation not only differs significantly from that of the existing empirical models for such flows but it also provides a novel understanding of the effect of rigid-like rotational regions in the flow.