The Influence of Bottom Geometry on Turbulent Flow Field in a Lid-Driven Cavity

Abstract

In this study, the effect of rib structures on the turbulent flow and heat transfer have been investigated numerically. six different Reynolds Numbers, two different rib geometry (sharp-edged square and rounded-edged square) and four different rib layout are carried out. Streamlines close to the ribbed area, velocities, temperature distributions and Nusselt Number distributions on the bottom surface are investigated. The results shows that, flow near the bottom surface behaves independently by the reason of small stable vortices arises among the little cavities between the rib geometries and this hydrodynamic field created by the bottom geometry has significant effects on heat transfer. Besides, it is found that, for all Reynolds numbers, the total heat transfer coefficient is prominently influenced in case of sharp edged square rib cross section, and most reduction on the heat transfer is observed in this case. The reduction in the total heat transfer coefficient in a given Reynolds number range has reached 25%.