Granular avalanches down inclined and vibrated planes
Naïma Gaudel1, Sébastien Kiesgen de Richter1, Nicolas Louvet1
1Laboratoire d'Énergétique et de Mécanique Théorique et Appliquée (LEMTA), Université de Lorraine-CNRS, UMR 7563, Vandœuvre-lès-Nancy 54504, France.
Physical Review. E
|October 15, 2016
Summary
External mechanical vibrations can control granular avalanches on inclined planes. This study identifies flow arrest conditions and proposes an empirical law for deposit thickness, revealing distinct gravity-driven and vibration-driven flow regimes.
Area of Science:
- Physics
- Geophysics
- Complex Systems
Background:
- Granular avalanches on inclines are well-studied phenomena.
- External factors can influence granular flow dynamics.
- Understanding flow arrest is crucial for predicting avalanche behavior.
Purpose of the Study:
- To investigate the effect of external mechanical vibrations on granular avalanches.
- To identify conditions leading to flow arrest under vibration.
- To develop an empirical law for deposit thickness and analyze flow regimes.
Main Methods:
- Experimental study of granular avalanches with applied mechanical vibrations.
- Comparison of flow arrest conditions with non-vibrating systems.
- Development of an empirical law relating deposit thickness to inclination angle and vibration intensity.
- Analysis of surface velocity and flow depth to understand competing forces.
Main Results:
- Identified conditions for flow arrest influenced by vibrations.
- Proposed an empirical law for deposit thickness based on inclination and vibration intensity.
- Distinguished between gravity-driven flows (large angles) and vibration-driven flows (small angles).
- Observed that vibrations do not alter dynamics in gravity-driven flows but significantly impact vibration-driven flows.
Conclusions:
- External mechanical vibrations offer a method to finely tune granular flows down inclined planes.
- Two distinct flow regimes (gravity-driven and vibration-driven) were identified and characterized.
- The study provides insights into the interplay between gravity, vibrations, and granular material flow behavior.
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