Nomenclature

Abstract: The direct numerical simulation (hereafter, DNS) of turbulent heat transfer in a plane Couette flow at Reynolds number equal to 8600 (based on the relative wall speed and the channel width) has been performed with emphasis on a large-scale turbulence structure (LSS). Two kinds of boundary temperature conditions are employed; these are the uniform heat flux heating (UHF) and the constant temperature difference between the both walls (CTD). A series of present DNS has been carried out for several larger computational box-sizes than those of existing DNS to examine their effect upon the LSSs and the statistical quantities such as temperature variance. The differences caused by the box-size and the boundary conditions of temperature field are discussed with respect to LSS