Dissimilarity between heat and momentum transfer in transitional channel flow

Abstract

There is a strong similarity between heat and momentum transfer, and thus simultaneous achievement of enhancement of heat transfer and reduction of momentum transfer is a challenging goal for turbulence control. In this study, we perform direct numerical simulation in a low Reynolds number range for transitional channel flow. In the simulations, stripe-like localized structures and spot-like localized turbulence structures are observed, and dissimilarity in which heat transfer dominates momentum transfer is significant for spot-like structures. We explain the mechanism of emergence of this dissimilarity.