Turbulent transport of material particles: an experimental study of finite size effects.
نویسندگان
چکیده
We present experimental Lagrangian statistics of finite sized, neutrally bouyant, particles transported in an isotropic turbulent flow. The particle's diameter is varied over turbulent inertial scales. Finite size effects are shown not to be trivially related to velocity intermittency. The global shape of the particle's acceleration probability density functions is not found to depend significantly on its size while the particle's acceleration variance decreases as it becomes larger in quantitative agreement with the classical k(-7/3) scaling for the spectrum of Eulerian pressure fluctuations in the carrier flow.
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عنوان ژورنال:
- Physical review letters
دوره 99 18 شماره
صفحات -
تاریخ انتشار 2007