Study of fully-developed turbulent flow and heat transfer in a rotating wavy-walled duct

Abstract

Finite volume based computations of fully developed flow and heat transfer through rotating wavy-walled ducts using large eddy simulation (LES) has been carried out. The shear improved Smagorinsky model (SISM) is employed to model the unresolved turbulent fluctuations. The wavy-walls of the duct are described by the sine function y=2asin2(πx/L). The geometrical ratios Hmin/Hmax and L/a are kept fixed to 0.2 and 8 respectively. The effect of rotation on the fluid flow and heat transfer characteristics are presented. All the computations are at a Reynolds number of 5000 and the rotation number is varied in the range, 0–0.5. It has been observed that the pressure drop across the wavy-walled duct varies with increasing rotation number. It is also found out that with rotation, the heat transfer increases on the trailing wall while the leading wall shows the opposite trend. Both Nusselt number and pressure drop for the wavy-walled duct is observed to be less than the corresponding values in ribbed duct geometry.