Fourth International Symposium on Turbulence and Shear Flow Phenomena
DOI: 10.1615/TSFP4
DNS OF TURBULENT HEAT TRANSFER IN A CHANNEL FLOW WITH STREAMWISELY VARYING THERMAL BOUNDARY CONDITION
pages 647-652
DOI: 10.1615/TSFP4.1090
要約
The direct numerical simulation (DNS, hereafter) of turbulent heat transfer in a fully developed turbulent channel flow has been carried out for streamwisely varying thermal boundary condition (Reτ = 180) with Pr = 0.71 to obtain the statistical mean temperature, the temperature variance, their budget terms and the time scale ratio etc. The present results have indicated that the time scale ratio and the turbulent Prandtl number vary along a streamwise direction. Therefore, the turbulent Prandtl number cannot be used for the estimation of the turbulent heat flux in the case of thermal boundary condition with rapid streamwise variation. The counter gradient diffusion takes place near the heated wall and downstream.