Prediction of heat transfer with $k-ε-f_μ$ model for an impinging jet flow

Abstract

A numerical prediction was made of heat and fluid flow for an impinging jet flow. The $k-ε-f_μ$ model was applied, which is a low-Reynolds-number k-ε model for predictions involving multiple wall surfaces. The realizability constraint was imposed on the turbulent time scale to prevent excessive production of turbulent kinetic energy near the stagnation point. The model performance was validated by the relevant experimental data. The model comparison with the k-ε model and the $k-ε-v^2$ were made. The jet-to-plate distances of 2,4,6, and 10 diameters above a plate were tested. The Reynolds numbers based on the bulk velocity of fully developed jet were 23,000,50,000 and 70,000. The present numerical predictions of the wall heat transfer show good agreement with the measured data in the stagnation region while the k-ε predictions produce too high heat transfer coefficients. The influences of the Reynolds number and jet-to-plate distance on the stagnation Nusselt number were investigated. The results are in good agreement with experimental studies.