On the large eddy simulation of a turbulent channel flow with significant heat transfer

Abstract

A large eddy simulation of a planar channel flow with significant heat transfer at a low Mach number was performed to study effects of fluid property variations on the near-wall turbulence structure. A compressible dynamic subgrid scale model was used to model the residual-scale turbulence. Two low Reynolds number channel flows with one wall heated and one wall cooled at temperature ratios of 1.02 and 3.0 were simulated to study the effects of property variations at low Mach number. Several features of the flow were observed to vary with the heat transfer level including velocity and temperature rms values. Specifically, the temperature-velocity correlations were found to exhibit stronger dependency on heat transfer rate. At the higher heat transfer rate, density fluctuations at levels characteristic of flows at much higher Mach numbers were observed. Heating appeared to enhance velocity fluctuations whereas density and temperature percentage fluctuations were greatest near the cooled wall when scaled by their local mean values.