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Longitudinal and Transverse structure functions in high Reynolds-number turbulence

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 نشر من قبل Rainer Grauer
 تاريخ النشر 2010
  مجال البحث فيزياء
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Using exact relations between velocity structure functions (Hill, Hill and Boratav, and Yakhot) and neglecting pressure contributions in a first approximation, we obtain a closed system and derive simple order-dependent rescaling relationships between longitudinal and transverse structure functions. By means of numerical data with turbulent Reynolds numbers ranging from $Re_lambda=320$ to $Re_lambda=730$, we establish a clear correspondence between their respective scaling range, while confirming that their scaling exponents do differ. This difference does not seem to depend on Reynolds number. Making use of the Mellin transform, we further map longitudinal to (rescaled) transverse probability density functions.



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