Sinking of light intruders in a shaken granular bed.

نویسندگان

  • Iván Sánchez
  • Gustavo Gutiérrez
  • Iker Zuriguel
  • Diego Maza
چکیده

We present an experimental study of the displacement of a light intruder immersed in a vibrated granular bed. Using high speed video we resolve the motion, during one cycle of oscillation, of a cylindrical object inside a Plexiglas box partially filled with grains. We report experimental evidence that, in the absence of convection, at least two forces are behind the intruder's motion: an air drag force--due to the airflow through the granular bed--and a buoyancy force produced by an air-mediated granular fluid.

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عنوان ژورنال:
  • Physical review. E, Statistical, nonlinear, and soft matter physics

دوره 81 6 Pt 1  شماره 

صفحات  -

تاریخ انتشار 2010