Large eddy simulation of turbulent heat transfer in an orthogonally rotating rectangular duct with transverse rib turbulators

Abstract

Heat transfer in a rotating rectangular rib-roughened duct was numerically simulated by using the second order finite difference method. In order to investigate the effect of the Coriolis force and the cross-sectional aspect ratio on the turbulence, the large eddy simulation was adopted with a dynamic subgrid scale model. The rotation number (0 and 1.0) and the cross-sectional aspect ratio (1.0, 2.0, 4.0) were varied while the turbulent Reynolds number was set to be a constant value, 350. The present results clearly showed the locally high heat transfer coefficient at two locations: in front of the rib on the rib-roughened walls and around the rib on the side walls. The effect of rotation was seen in the increased and decreased heat transfer on pressure and suction surfaces, respectively. The heat transfer enhancement caused by the rotation was larger for the higher aspect ratio case.