Evaluation of a developed SST k-ω turbulence model for the prediction of turbulent slot jet impingement heat transfer

摘要

In this paper, a turbulence model based on OpenFOAM has been developed for the jet impingement heat transfer, which is based on the standard SST k-omega model and considers the effects of cross-diffusion term and the Kato-Launder model. The effects of the modifications have been studied for different nozzle-plate spacing of 4 and 9.2 in terms of pressure distributions, mean velocity, skin friction and the local Nusselt number distributions. The results have been compared with both the experimental data and the numerical results in the literatures. Good agreement is obtained in the studied cases and the developed model overcomes the false secondary Nusselt number peak in high nozzle-plate spacing for slot jets which is predicted by the standard SST k-omega model. The results show that the modifications improve the model's ability to predict the heat transfer for jet impingement by reinforcing the model's sensitivity to the pressure gradient. By way of comparative studies, it shows that the SST k-omega with transition model and the standard SST k-omega model are not sensitive to the pressure gradient. Meanwhile, the cases of nozzle-plate spacing of 2 and 6 are also investigated. This investigation indicates that the pressure gradient plays an important role for turbulent slot impinging jet. And it also reveals that the effect of cross-diffusion term should not be ignored in the boundary layer. (C) 2019 Elsevier Ltd. All rights reserved.