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Prandtl-Blasius temperature and velocity boundary layer profiles in turbulent Rayleigh-B{e}nard convection

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 نشر من قبل Quan Zhou
 تاريخ النشر 2010
  مجال البحث فيزياء
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The shape of velocity and temperature profiles near the horizontal conducting plates in turbulent Rayleigh-B{e}nard convection are studied numerically and experimentally over the Rayleigh number range $10^8lesssim Ralesssim3times10^{11}$ and the Prandtl number range $0.7lesssim Prlesssim5.4$. The results show that both the temperature and velocity profiles well agree with the classical Prandtl-Blasius laminar boundary-layer profiles, if they are re-sampled in the respective dynamical reference frames that fluctuate with the instantaneous thermal and velocity boundary-layer thicknesses.

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