Kraichnan's random sweeping hypothesis in homogeneous turbulent convection.

نویسندگان

  • Xiaozhou He
  • Penger Tong
چکیده

We report an experimental study of the temperature space-time cross-correlation function, C{T}(r,τ), in the central region of turbulent Rayleigh-Bénard convection. The measured C{T}(r,τ) is found to have the scaling form C{T}(r{E},0), where r{E}=[r² +(Vτ)²]¹/² with V being the rms velocity at the center of the convection cell. The experiment confirms the theory by He et al. [Phys. Rev. E 73, 055303(R) (2006)] and demonstrates its applications to homogenous turbulent flows, where the mean flow velocity is zero and Kraichnan's random sweeping hypothesis holds approximately.

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عنوان ژورنال:
  • Physical review. E, Statistical, nonlinear, and soft matter physics

دوره 83 3 Pt 2  شماره 

صفحات  -

تاریخ انتشار 2011