Scaling properties of the equation for passive scalar transport in wall-bounded turbulent flows

Abstract

Data from direct numerical simulations (DNS) of fully-developed turbulent channel flows subjected to a constant surface heat-flux are used to explore the scaling behaviours admitted by the mean thermal energy equation. Following the framework of Wei et al. (2005) [1,2], the analysis employs a theory based on the magnitude ordering of terms in the mean thermal energy equation of wall-bounded turbulent heat transfer. A four layer thermal structure has been identified from the leading order terms in the mean energy equation. A review of the limitations of traditional and existing scaling of mean temperature and turbulent heat flux is conducted. The possibilities of a new scaling approach with t..