Daikin UWL-B5 Series Catalogue/Engineering Data page 26

* Determining the diameter of pipes in the air conditioning system
The pipe diameter is determined based on the following:
d
=
3
m = water flow m /s
w
v = water speed m/s
The water speed should be determined by the recommendations in the first table and design the water pipe diameters
accordingly, or you can determine the water pipe diameter based on water flow in the second table.
Table 1: Recommended water speed (m/s)
Diameter (mm)
Closed water system
Open water system
Diameter (mm)
Closed water system
Open water system
Table 2: Pipe diameter and resistance loss in unit length
Diameter of the steel
tube (mm)
15
20
25
32
40
50
65
80
100
125
Note: Parameters in the preceding table may vary based on the design manual. For details, see the <HVAC Design Manual>.
4 m
w
. 3 14 v
12 20
0.4 - 0.5 0.5 - 0.6 0.6 - 0.7
0.3 - 0.4 0.4 - 0.5 0.5 - 0.6
100 125
1.3 - 1.8 1.5 - 2.0 1.6 - 2.2
1.2 - 1.6 1.4 - 1.8 1.5 - 2.0
Closed water system
Water flow (m3/h)
0 - 0.5
0.5 - 1.0
1.0 - 2.0
2.0 - 4.0
4.0 - 6.0
6.0 -11.0
11.0 -18.0
18 - 32
32 - 65
65 - 115
25 32 40
0.7 - 0.9 0.8 - 1.0
0.6 - 0.8 0.7 - 0.9
150 200 250
1.8 - 2.5 1.8 - 2.6
1.6 - 2.3 1.7 - 2.4
kPa/100m Water flow (m3/h)
0 - 60
10 - 60
10 - 60
10 - 60
10 - 60
10 - 60
10 - 60
10 - 60
10 - 60
10 - 60
50 65
0.9 - 1.2 1.1 - 1.4
0.9 - 1.0 0.9 - 1.2
300 350
1.9 - 2.9 1.6 - 2.5
1.7 - 2.4 1.6 - 2.1
Open water system
kPa/100m
--
--
0 - 1.3
1.3 - 2.0 11 - 40
2.0 - 4.0 10 - 40
4.0 - 8.0
8.0 -14.0
14 - 22
22 - 45
45 - 82 10 - 40
80
1.2 - 1.6
1.1 - 1.4
400
1.8 - 2.6
1.8 - 2.3
--
--
0 - 43
--
--
--
--
25