35
The calculation of the humidification distance “B
N
” is dependent on several
factors. For a rough estimation of the humidification distance “B
N
”, the fol
lowing table is useful. Recommended standard values listed in this table
are based on a supplyair temperature range of 15 °C to 30 °C. The values
given in bold type
only apply to steam distribution pipes DV41-... and
DV71-...
, the values
in brackets apply to the MultiPipe steam distribu-
tion system.
Humidity at inlet
ϕ
1 in %rh
Length of humidification distance B
N
in m
Humidity at outlet
ϕ
2 in %rh
40
50
60
70
80
90
5
0,9
(0,22)
1,1
(0,28)
1,4
(0,36)
1,8
(0,48)
2,3
(0,66)
3,5
(1,08)
10
0,8
(0,20)
1,0
(0,26)
1,3
(0,34)
1,7
(0,45)
2,2
(0,64)
3,4
(1,04)
20
0,7
(0,16)
0,9
(0,22)
1,2
(0,30)
1,5
(0,41)
2,1
(0,58)
3,2
(0,96)
30
0,5
(0,10)
0,8
(0,17)
1,0
(0,25)
1,4
(0,36)
1,9
(0,52)
2,9
(0,88)
40
–
0,5
(0,11)
0,8
(0,20)
1,2
(0,30)
1,7
(0,45)
2,7
(0,79)
50
–
–
0,5
(0,13)
1,0
(0,24)
1,5
(0,38)
2,4
(0,69)
60
–
–
–
0,7
(0,16)
1,2
(0,30)
2,1
(0,58)
70
–
–
–
–
0,8
(0,20)
1,7
(0,45)
φ1 in %rh: Relative supply air humidity prior to humidification at the lowest supply air
temperature
φ2 in %rh: Relative supply air humidity after the steam distribution pipe at maximum
capacity
For duct widths <600 mm the humidification distance for the MultiPipe system increases
by approx. 50%
5.4.2
Positioning of the steam distribution pipes
The location for the steam distribution pipes should be determined at the
time of dimensioning the air conditioning system. Please note the following
instructions to ensure proper humidification of the duct air.
Calculating the humidification distance
The water vapour, emitting from the steam distribution pipes, requires a
certain distance to be absorbed by the ambient air so that it is no longer
visible as steam. This distance is referred to as
humidification distance
“B
N
”
and serves as a basis for the determination of the minimum distances
from the upstream components in the system.
B
N
: Humidification distance B
N
E
: Expansion and mixing zone
φ
1
: Supply air humidity
before
humidification
φ
2
: Supply air humidity
after
humidification
Summary of Contents for AT4 13064
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Page 64: ...64 Notes...
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