Energetic instability unjams sand and suspension

Area of Science:

• Physics
• Materials Science
• Rheology

Background:

• Jamming is a critical phenomenon observed across diverse systems, including granular materials, colloidal suspensions, and traffic flow.
• Understanding the reversible elastic deformation of jammed states is crucial for predicting material behavior and system dynamics.

Purpose of the Study:

• To develop a theoretical framework for the reversible elastic deformation of jammed states.
• To derive an explicit granular stress-strain relation capturing key features of granular materials.
• To generalize this theory for jammed magnetorheological and electrorheological fluids.

Main Methods:

• Derivation of an explicit granular stress-strain relation.
• Modeling of Coulomb yield surface and third-order jamming transitions.
• Generalization of the theory to include magnetorheological and electrorheological fluids.

Main Results:

• The derived stress-strain relation accurately captures essential features of sand, including the Coulomb yield surface.
• The theory successfully predicts a third-order jamming transition.
• The generalized approach shows good agreement with experimental and simulation results for jammed fluids.

Conclusions:

• The presented theory provides a robust framework for understanding reversible elastic deformation in jammed systems.
• The model's success with both granular materials and complex fluids highlights its broad applicability.
• This work offers valuable insights for materials science and soft matter physics research.