Multi-time-scale turbulent heat transfer model for predictions of various turbulent heat transfer phenomena

Abstract

The turbulent heat transfer model has been a useful and powerful tool in the calculation of turbulence heat transfer for designs of equipment with engineering and industrial problems. Among turbulent heat transfer models, two-equation turbulence models for both velocity and thermal fields are one of the best models because they have more accurate prediction performance and can carry out turbulence calculations at the proper calculation costs. In this study, in order to improve the prediction performance of two-equation heat transfer turbulence model in more complex problems of turbulent heat transfer, a turbulence model based on the multi-time-scale model proposed by Nagano and Hattori (Int J Heat Fluid Flow 51:221, 2015) for predictions of a velocity field is modified, and a turbulent heat transfer model with the multi-time-scale is newly proposed. The proposed turbulent heat transfer models are evaluated in complex fields of turbulent heat transfer problem such as a T-junction turbulent thermal mixing channel flow, a turbulent plane impinging jet with heat transfer and a turbulent plane wall jet with heat transfer, where databases of these complex turbulent heat transfer phenomena are obtained by our DNS. Based on the results, adequate improvement of the prediction performance of a proposed turbulent heat transfer model is validated.