Dynamic aerofracture of dense granular packings
Michael J Niebling1, Renaud Toussaint, Eirik G Flekkøy
1Department of Physics, University of Oslo, PO Box 1048, 0316 Oslo, Norway.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 2, 2013
Summary
This study reveals how granular displacement patterns transform from fractures to bubbles under hydraulic pressure. The findings detail a mechanism controlling this transition based on gas and granular properties.
Area of Science:
- Physics
- Materials Science
- Fluid Dynamics
Background:
- Granular materials exhibit complex flow behaviors under pressure.
- Understanding displacement patterns is crucial for various industrial applications.
Purpose of the Study:
- To investigate the transition of hydraulically induced granular displacement patterns.
- To identify the mechanism controlling pattern evolution from fractures to bubbles.
Main Methods:
- Discrete numerical molecular dynamics simulations were employed.
- Experiments were conducted in a rectangular Hele-Shaw cell with a 2D granular layer.
- A pressure gradient was applied to a compressible interstitial gas.
Main Results:
- Observed a transition from fracture and finger patterns to finely dispersed bubbles.
- Identified a mechanism governing this pattern transition.
- The transition is dependent on interstitial gas properties and granular phase characteristics.
Conclusions:
- The study elucidates the dynamics of granular displacement under hydraulic pressure.
- A clear mechanism for pattern transformation was described.
- Results provide insights into controlling granular flow behavior.
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