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Pictures for illustra tive purpos es
Evaporation distance or vapor trail « D »
A certain length is required so that the steam coming out of the steam distribution pipe
be absorbed by the air. All along this length, descrided as the evaporation distance, the
steam can still be seen in the airflow as a mist w hich can condensate in w ater against any
obstacle if placed w ithin. To prevent condensation, this evaporation distance should be
calculated before positioning the steam distribution pipe.
How to calculate the evaporation distance « D » (FAST METHOD)
In order to determine the evaporation distance, the attached calculation table can be used :
Nota bene : this calculation table is to be used for temperatures betw een 20°C and 25°C.
HR1 = relative humidity of air before humidification in %.
HR2 = relative humidity of air after humidification in %.
Minimal humidification distance
The steam distribution pipes must be positioned after the minimum humidification
distance calculated w ith the help of the above table.
% RH1 inlet air
5
10
20
30
40
50
60
70
% HR2 outlet air
40
0,9
0,8
0,7
0,5
-
-
-
-
50
1,1
1
0,9
0,8
0,5
-
-
-
60
1,4
1,3
1,2
1
0,8
0,5
-
-
70
1,8
1,7
1,5
1,4
1,2
1
0,7
-
80
2,3
2,2
2,1
1,9
1,7
1,5
1,2
0,8
90
3,5
3,4
3,2
2,9
2,7
2,4
2,1
1,7
Minimum humidification distance « D » in m.
Before / after fan
before / after heater/filter
D
D
1,5 x D
5cm
2,5 x D before thin particule filter
E
LECTRO
V
AP
RTH-LC
Steam pipe positioning