Rotation of anisotropic particles in Rayleigh–Bénard turbulence

  title={Rotation of anisotropic particles in Rayleigh–B{\'e}nard turbulence},
  author={Linfeng Jiang and Enrico Calzavarini and Chao Sun},
  journal={Journal of Fluid Mechanics},
Abstract Inertialess anisotropic particles in a Rayleigh–Bénard turbulent flow show maximal tumbling rates for weakly oblate shapes, in contrast with the universal behaviour observed in developed turbulence where the mean tumbling rate monotonically decreases with the particle aspect ratio. This is due to the concurrent effect of turbulent fluctuations and of a mean shear flow whose intensity, we show, is determined by the kinetic boundary layers. In Rayleigh–Bénard turbulence prolate particles… 
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