2009/07/31 by Pankaj Kumar Mishra, Mahendra K. Verma · 84 citations
Earth and Planetary Sciences · Engineering · Environmental Science · Mathematics · Physics and Astronomy · #Buoyancy #Convection #Fluid Dynamics and Turbulent Flows #Geometry #Mathematics #Mechanics #Meteorological Phenomena and Simulations #Natural convection #Nusselt number #Optics #Physics #Plant Water Relations and Carbon Dynamics #Prandtl number #Rayleigh number #Rayleigh–Bénard convection #Reynolds number #Scaling #Turbulence #Turbulent Prandtl number #Wavenumber #physics.comp-ph #physics.flu-dyn
paper · pdf · doi:10.1103/physreve.81.056316
published in Physical Review E 81(5), 056316 (American Physical Society) · Final published version
openalex publication_date 2010/05/19 · arxiv created 2010/05/20 · arxiv updated 2010/05/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We compute the spectra and fluxes of the velocity and temperature fields in Rayleigh-Bénard convection in turbulent regime for a wide range of Prandtl numbers using pseudospectral simulations on 512(3) grids. Our spectral and flux results support the Kolmogorov-Obukhov (KO) scaling for zero Prandtl number and low Prandtl number (P=0.02) convection. The KO scaling for the velocity field in zero-Prandtl number and low-Prandtl number convection is because of the weak buoyancy in the inertial range (buoyancy is active only at the very low wave numbers). We also observe that for intermediate Prandtl numbers (P=0.2) the KO scaling fits better with the numerical results than the Bolgiano-Obukhov (BO) scaling. For large Prandtl number (P=6.8) , the spectra and flux results are somewhat inconclusive on the validity of the KO or BO scaling, yet the BO scaling is preferred over the KO scaling for these cases. The numerical results for P=1 is rather inconclusive.