Shear-banding instability in arbitrarily inelastic granular shear flows
Priyanka Shukla1, Lima Biswas1, Vinay Kumar Gupta2
1Department of Mathematics, Indian Institute of Technology Madras, Chennai 600036, India.
Physical Review. E
|October 24, 2019
Summary
Granular shear flows can develop shear-banding instabilities, forming dense and dilute particle bands. This study analyzes these instabilities using hydrodynamic equations, identifying key criteria for their onset.
Area of Science:
- Physics
- Fluid Dynamics
- Materials Science
Background:
- Granular flows exhibit instabilities, notably shear-banding.
- Shear-banding involves the formation of alternating dense and dilute particle bands.
- Understanding these instabilities is crucial for predicting granular material behavior.
Purpose of the Study:
- To analyze shear-banding instability in inelastic granular shear flows.
- To investigate the role of constitutive relations in predicting this instability.
- To determine criteria for the onset of shear-banding.
Main Methods:
- Linear stability analysis of granular hydrodynamic equations.
- Utilizing Navier-Stokes-level constitutive relations.
- Conducting a parametric study on key physical parameters.
Main Results:
- The choice of constitutive relations significantly impacts the prediction of shear-banding.
- Identified two global criteria for the onset of shear-banding instability.
- Investigated the effects of restitution coefficient, channel width, and mean density.
Conclusions:
- Constitutive relations are critical for modeling granular shear-banding.
- The study provides criteria to predict when shear-banding will occur.
- This research advances the understanding of complex granular flow dynamics.
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