Impact of a Control Rod on the Heat Transfer Enhancement of a Wall Jet

Document Type : Research Article

Authors

Faculty of Mechanical Engineering, University of Tabriz, Tabriz, Iran

Abstract

Influence of a control rod on the heat transfer characteristics of an incompressible wall jet with an isothermal plate boundary condition is investigated numerically in the turbulent regime. The main issue is to find an efficient way to increase the rate of convective heat transfer in the wall jet. The rod is placed in various horizontal and vertical locations. In addition, different diameters for the rod  are examined. The performance of realizable K-ϵ, standard K-ω, and shear stress transport turbulence models are compared with the experimental data to find the suitable one for the simulations. It was found that the shear stress transport model generates more accurate results than the others. The control rod with a particular diameter and location causes a noticeable enhancement in the heat transfer rate with a negligible increase in the skin friction coefficient. The results showed that the effect of the rod on the heat transfer enhancement increases with the Reynolds number. Two correlations were found as the variation of average Nusselt number and Stanton number against the Reynolds number, which could be used in designs and practices.

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