Rapporten från etapp 1 - BeBo

Distance between the pressure taps is as follows:
Figure 4. Length 3 large area duct setup with
Tap 2 in the foreground
Results
Table 1 Pressure tap distances
Pressure Taps Distance
Tap 1 to Tap 2 255 cm
Tap 2 to Tap 3 211,5 cm
Tap 3 to Tap 4 110 cm
The results of the laboratory experiment are below.
Once the ducts were put together, one size i.e., the
large area duct, was connected to the fan system.
The fan was set to deliver seven liters per second
and later twelve liters per second of air through the
ducts. Pressure drops were first measured for ten
minutes from Tap 1 to Tap 2, then Tap 1 to Tap 3,
then Tap 1 to Tap 4 or Length 1, Length 2 and
Length 3 respectively. This procedure was repeated
on the other duct system of different area.
To measure the sound, the sound meter was pointed
at the outlet of the duct, approximately one meter
away. According to building code standards, low
frequency sounds need to be minimized. The sound
experiments measured decibels from 125 Hz, 250
Hz and 500 Hz. In the laboratory, background noise
was reduced to a minimum, by performing tests
during non-working hours.
Bilaga 5 sid 3 (6)
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