Abstract
Direct numerical simulation of turbulent heat transfer in a channel flow through high spatial resolution has been carried out for Re_τ=180, which is based on the friction velocity and the channel half width. The configuration is a fully developed turbulent channel flow with uniform heat flux heated from both walls. Molecular Prandtl numbers are set to be 0.71, 1.0, 2.0 and 10.0. The Prandtl number effect on the turbulence quantities such as the turbulent Prandtl number and the cross-correlation between velocity and scalar fluctuations are examined. Moreover, the resulting one-dimensional pre-multiplied energy spectra of temperature fluctuations at large wavenumbers are investigated to confirm the accuracy of the calculation.
