Heat Transport Mechanism in Wall Turbulence on Convex and Concave Surfaces

摘要

The effect of wall curvature on the structure of turbulence and heat transfer in turbulent curved channel flow is investigated by means of direct numerical simulation (DNS). Four different radii of curvature, δ/ Rc=0.013, 0.05, 0.1 and 0,2, are studied. The DNS results show: 1) the reduction of temparature fluctuation on the convex side, and 2) the increase of radial turbulent heat flux in the central region of channel with the increase of curvature. It is revealed that such heat transport mechanism is attributed to the extra production rate of the turbulent heat flux due to the centrifugal force.