Particle scale dynamics in granular impact.

@article{Clark2012ParticleSD,
  title={Particle scale dynamics in granular impact.},
  author={Abram H. Clark and Lou Kondic and Robert P Behringer},
  journal={Physical review letters},
  year={2012},
  volume={109 23},
  pages={
          238302
        }
}
We perform an experimental study of granular impact, where intruders strike 2D beds of photoelastic disks from above. High-speed video captures the intruder dynamics and the local granular force response, allowing investigation of grain-scale mechanisms in this process. We observe rich acoustic behavior at the leading edge of the intruder, strongly fluctuating in space and time, and we show that this acoustic activity controls the intruder deceleration, including large force fluctuations at… 

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