Spectra and probability distributions of thermal flux in turbulent Rayleigh-Bénard convection

Abstract

The spectra of turbulent heat flux $\mathrm{H}(k)$ in Rayleigh-Bénard convection with and without uniform rotation are presented. The spectrum $\mathrm{H}(k)$ scales with wave number $k$ as $\sim k^{-2}$. The scaling exponent is almost independent of the Taylor number $\mathrm{Ta}$ and Prandtl number $\mathrm{Pr}$ for higher values of the reduced Rayleigh number $r$ ($>10^3$). The exponent, however, depends on $\mathrm{Ta}$ and $\mathrm{Pr}$ for smaller values of $r$ ($<10^3$). The probability distribution functions of the local heat fluxes are non-Gaussian and have exponential tails.

22 pages, 6 figures

References in corpus (10)

• Large scale dynamics in turbulent Rayleigh-Benard convection
• Scaling in thermal convection: A unifying theory
• Energy Spectrum of Buoyancy-Driven Turbulence
• Energy spectra and fluxes for Rayleigh-Benard convection
• Spectra and statistics of velocity and temperature fluctuations in turbulent convection
• Evidences of Bolgiano scaling in 3D Rayleigh-Benard convection
• Fluctuations of energy flux in wave turbulence
• Transitions in turbulent rotating Rayleigh-Bénard convection
• Entropy and energy spectra in low-Prandtl-number convection with rotation
• Frequency spectra of turbulent thermal convection with uniform rotation

Cited by in corpus (2)

• Prandtl number dependence of the small-scale properties in turbulent Rayleigh-Bénard convection
• Similarity model for corner roll in turbulent Rayleigh-Benard convection