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The characteristics of heat transfer from a hot wall surface for the oblique impingement of a free turbulent slot jet have been investigated numerically. Different turbulent models — the k - ϵ , k - ω , SST k - ω , cubic k - ϵ and quadratic k - ϵ models — are used for the prediction of heat transfer and their results were compared with experimental results reported in the literature. The comparison shows that the k - ϵ , quadratic k - ϵ and SST k - ω models give more unsatisfactory results for the investigated configuration, while the cubic k - ϵ model is capable of predicting the local Nusselt number in wall-jet region only. The k - ω model exhibits the best agreement with the experimental results in both stagnation and wall-jet regions. Further, the k - ω model is applied to analyze the obliquely impinging jet heat transfer problem. The parametric effects of the jet inclination (ϕ = 5 0 ∘ , 7 0 ∘ and 9 0 ∘ ), jet-to-surface distance ( d L = 4 , 6 and 8), Reynolds number (Re = 1 2 0 0 0 , 15 000 and 20 000), and turbulent intensity (I = 5 % , 7. 5 % and 1 0 %) have been presented. The heat transfer on the upward direction is seen to decrease, while that on the downward direction it rises for the increasing angle. It is to be noted that as the value of ϕ decreases, the point of maximum Nusselt number ( Nu max ) displaces toward the upward direction from the geometric center point as well as its value reduces. The shifting of the Nu max is found to be independent of Re and d L within the range considered for the study. [ABSTRACT FROM AUTHOR]

A dimensionless numerical investigation of turbulent flow and heat transfer characteristics due to the impingement of a free inclined slot jet onto the moving hot surface has been performed using the k − ω turbulence model. The parameters considered for the investigation are: the Reynolds number, impingement angle and plate velocity. The influence of parameters on the properties such as the pressure and velocity profiles, skin-friction coefficients, Nusselt number, interface temperature, and the location of stagnation has been presented. The displacement of stagnation point depends primarily on ϕ , whereas the effect of plate velocity is less significant. These relocations are found in between X = − 2 to 0. The effect of plate velocity on average skin-friction coefficient is continuously decreasing with increase in jet angle. A continuous increase in average Nu has been found with increase in Re for all values of ϕ and U p considered in the present study. It is revealed that the change in plate velocity has more influence on the average Nu for lower angles of impingement. Further reduction in the impingement angle shows an adverse effect on the average Nu. Correlations have been developed for Nusselt number at different zones based on the parameters considered for the study. [ABSTRACT FROM AUTHOR]