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Lagrangian temperature, velocity and local heat flux measurement in Rayleigh-Benard convection

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 نشر من قبل Jean-Francois Pinton
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Yoann Gasteuil




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We have developed a small, neutrally buoyant, wireless temperature sensor. Using a camera for optical tracking, we obtain simultaneous measurements of position and temperature of the sensor as it is carried along by the flow in Rayleigh-Benard convection, at $Ra sim 10^{10}$. We report on statistics of temperature, velocity, and heat transport in turbulent thermal convection. The motion of the sensor particle exhibits dynamics close to that of Lagrangian tracers in hydrodynamic turbulence. We also quantify heat transport in plumes, revealing self-similarity and extreme variations from plume to plume.



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