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part of the plate. Downstream of this region, it recovers very small values. As expected,
near the perforated plate the values of velocity are approximately 0.5 σ V j , corresponding to
the bulk vertical velocity.
Figure 12. Field and isolines of time-averaged vertical velocity field over the cutting plane z = 0
using model UM2. Scale is from 0 (white) to 0.025 V j (black). Two isolines are represented, at
0.005 V j and 0.01 V j . Zoom on the section between 120 d < x < 288 d.
In order to obtain a quantitative assessment of the models, all the experimental profiles
available for row 9 of the LARA experiment have been averaged for comparison with the
numerical results. Eight experimental profiles are available at row 9, their locations being
displayed by crosses in Fig. 13.
NINTH ROW
Eighth row
Tenth row
DIRECTION
OF THE FLOW
d
z = 0
x
z
x = 0
Figure 13. Zoom on the ninth row of the experimental test rig. The locations of the profiles
measured in the experiment are represented by crosses.
Experimental spatial-averaged profiles are calculated from these eight profiles. The four
profiles located at z = 0 are averaged together, then this profile is averaged with the other
ones at z ≠ 0. In other words, the eight experimental profiles are summed with a weight
of 0.05 for the ones located at z = 0 and 0.2 for the remaining ones (z ≠ 0). Of course,
the resulting profile is only an approximation of the surface-averaged profile, used thereafter
for comparison with numerical results. This comparison is shown in Fig. 14, from the wall
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