This is a low speed flow of a turbulent jet impinging on an isothermally heated plate. The jet emanates from a pipe which ends 2 pipe diameters ahead of the plate, allowing the jet to form at the pipe exit and hit the plate (Fig. 1). The shear layer from the pipe becomes the outer boundary of this jet. As it impinges on the plate, the highly turbulent shear layer hits the newly developing plate boundary layer about 2 diameters away from the stagnation point, where a secondary peak in heat transfer occurs due to the local increase in turbulence intensity.

Several sets of experimental data are available for this flow. Here we compute the case for air at  and compare predictions with data by Baugh et al. [1] and by Yan [2]. Flow conditions are:  Figure 1 is a sketch showing topology and main flow features.

To predict this flow a 50 diameter long adiabatic wall pipe was used to insure that the flow becomes fully developed before the pipe end is reached. A 60,000 size grid was employed for the calculations. The mesh was fine enough (< 1) to integrate the equations to walls without the need for wall functions. Fig. 2 shows wall heat transfer predictions in Nusselt Number form. The k-ℓ model is seen to capture the heat transfer distribution very well, including the secondary peak The SST closure fails to predict this peak. The superior performance of the k-ℓ model is due to its variable function.

[2] X.Yan, J. W. Baughn and M. Mesbah, “The effect of Reynolds number on the heat transfer distribution from a flat plate to an impinging jet,” ASME Heat Transfer Division, Vol. 226, pp. 1-7, 1992.