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Preferential concentration of free-falling heavy particles in turbulence

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 نشر من قبل Florencia Falkinhoff Ms
 تاريخ النشر 2020
  مجال البحث فيزياء
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We present a sweep-stick mechanism for heavy particles transported by a turbulent flow under the action of gravity. Direct numerical simulations show that these particles preferentially explore regions of the flow with close to zero Lagrangian acceleration. However, the actual Lagrangian acceleration of the fluid elements where particles accumulate is not zero, and has a dependence on the Stokes number, the gravity acceleration, and the settling velocity of the particles.

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