A non-local rheology for dense granular flows.

Area of Science:

• Physics
• Materials Science
• Fluid Dynamics

Background:

• Dense granular flows exhibit complex behaviors driven by particle rearrangements.
• Existing models often struggle to capture the non-local interactions and broad applicability across flow regimes.

Purpose of the Study:

• To propose a novel non-local theory for modeling dense granular flows.
• To describe particle rearrangements as a self-activated process triggered by stress fluctuations.
• To develop a constitutive law applicable from quasi-static to inertial regimes.

Main Methods:

• Developed a non-local theory describing granular flow rearrangements as a self-activated process.
• Formulated a constitutive law as an integral over the entire flow, relating shear rate to stress distribution.
• Incorporated finite rearrangement times to ensure applicability across different flow regimes.

Main Results:

• The proposed non-local theory successfully models dense granular flows.
• The model accurately predicts experimental observations in configurations like inclined planes and plane shear under gravity.
• The theory demonstrates applicability across quasi-static and inertial flow regimes.

Conclusions:

• The self-activated non-local theory provides a unified framework for dense granular flows.
• The model's ability to predict experimental data validates its approach.
• This work offers a new perspective on understanding and modeling granular material behavior.