The computation of turbulent natural convection flows - Turbulence ...

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not sufficiently detailed to provide confirmation for this feature, but they cer-
tainly confirm that the RSM model returns the correct Nusselt number levels
at the locations at which measurements are available.
Figures 7.60-7.61 show vector plots and mean temperature contours within
spanwise, x-z, planes at longitudinal locations Y=0.1, 0.5 and 0.9. Both sets of
plots indicate the presence of three longitudinal vortices, which extend over
the entire length of the cavity. The time-averaged velocities resulting from
the k-ε-AWF produced four longitudinal vortices. The experimental measure-
ments do not cover the entire length in the spanwise direction. With assump-
tion of symmetric flow and extrapolation of the experimental data, it can be
concluded that there are four longitudinal vortices, but on the other hand the
RSM spanwise profiles are closer to the experimental data. Figure 7.62 shows
the velocity vector plot contours and the mean temperature, within the central,
Z=0.5, longitudinal, x-y, plane. They confirm that in the cavity core conditions
are practically isothermal, with the temperature close to the average of the hot
and cold side temperatures and that the flow velocity is stronger near the end
walls. Figure 7.63 presents the vector plot and mean temperature contours
within the plane parallel to the thermally active planes, y-z, at the halfway lo-
cation, X=0.5. Again both plots show the presence of three longitudinal cells
which extend over most of the length of the cavity. This is consistent with the
predicted presence of the three longitudinal vortices shown Figures 7.60 and
7.61.