Dissimilar heat transfer enhancement by introduction of slit fins in turbulent channel flow

Abstract

We have conducted direct numerical simulations for turbulent heat and momentum transfer in plane channel flow with fins which are streamwise-slit flat plates. The slit fins are introduced by the immersed boundary method. All simulations were conducted at the friction Reynolds number Reτ = 200 and the Plandtl number Pr = 1. It is found that the slit fins lead to dissimilar heat transfer enhancement. As the thickness of the fins is increased, heat and momentum transfer are simultaneously enhanced, and significant dissimilarity between heat and momentum transfer is observed. The dissimilar heat transfer enhancement is attributed to large-scale roll structures.