Milnor 6458, Руководство по установке

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Pellerin Milnor Corporation
3.4. Pressure Drop Equations and Examples
BNDDUI01.C14 0000087352 A.10 A.11 Released
Calculate the pressure drop for each straight length of duct as follows:
PD
s
= PD
100
x L / 100
Where:
PD
s
= Pressure drop for a straight length
PD
100
= Pressure drop per 100 feet (or 100 meters) as given in table
L = Length of straight section in feet (or meters)
The following examples calculate the pressure drop for the 10 ft (3.05 M) length of rectangular
duct in Figure 3.
English example:
0.3 x 10 / 100 = 0.03 iwc
Metric example:
243 x 3.05 / 100 = 7.47 Pa
Calculate the total pressure drop as follows:
PD
T
= PD
1
+ PD
2
+ PD
3
+ ... + PD
n
+ PD
F
Where:
PD
T
= Total external pressure drop
PD
1
= Pressure drop for the most upstream (inlet-end) component
PD
2
, PD
3
, ... = Pressure drop for each next duct component in sequence
PD
n
= Pressure drop for the most downstream (exhaust-end) component
PD
F
= Pressure drop contributed by the external lint collection system, if
any.
The following examples calculate the total pressure drop for the layout shown in Figure 3, page 7
after the pressure drops for all straight sections have been calculated. The dryer in the example
layout uses internal lint screens. The installation does not have a separate, external lint collection
system.
English example:
0.08 + 0.08 + 0.03 + 0.009 + 0.009 + 0.06 + 0.036 + 0.06 + 0.06 = 0.424 iwc
Metric example:
20 + 20 + 7.47 + 2.24 + 2.24 + 15 + 8.97 + 15 + 15 = 105.92 Pa
End of document: BNDDUI01
Air and Duct Requirements for Milnor ® Pass-through Dryers
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