EFFECT OF DIMPLE ARRANGEMENTS ON THE TURBULENT HEAT TRANSFER IN A DIMPLED CHANNEL

Large eddy simulations (LES) have been conducted for the flow and heat transfer in a dimpled channel at the bulk Reynolds number of 20,000 to study the effect of dimple arrangements. Dimples are placed on one side of the channel in three canonical arrangements: in-line, staggered, or with cylindrical grooves. Heat transfer is not actively augmented at the spanwise gap between dimples for the in-line arrangement, while the problem can be cured by adopting the staggered arrangement. The cylindrical grooves provide heat transfer enhancement effect as much as the staggered arrayed dimples do.