7
TPI 16-05
Stating the damper parameters
Example 1:
Given are:
Searched for:
Flow velocity in the duct
v = 6 m.s
-1
Blade positioning angle
α
= ?°
Pressure drop
∆
p = 100 Pa
Acoustic power
L = ? dB(A)
In Diagram 1 we can find the points of intersection of the given values. By interpolating between the curves we can deter-
mine that the angle of the blade position for the given values should be equal
α
= 25° while L = 84 dB(A).
Example 2:
Given are:
Searched for:
Duct with damper
a=1400 mm, b=1600 mm
Flow when damper closed
q
C
= ? m
3
.h
-1
Pressure drop
∆
p = 100 Pa
Besides the flow q
VLBA
diagram 2 states also the class of damper tightness represented by the IMOS-RKT curve. We will
determine the point of intersection of the pressure drop on the given line and will subtract the value of the flow q
VLBA
= 68,4
m
3
.h
-1
.m
-2
. We will then determine the cross-section of the duct from the relationship S = axb = 1,4x1,6 = 2,24 m
2
. Accord-
ingly, the total flow through the damper will be q
C
= q
VLBA
. S = 68,4 x 2,24 = 153,2 m
3
.h
-1
.
Explanatory notes:
a - a- damper width [mm]
∆
p - pressure difference in flow meter [Pa]
b - b- damper height [mm]
q
C
- flow when damper closed [m
3
.h
-1
, l.s
-1
]
v - flow velocity in the duct [m.s
-1
]
q
vLBA
- flow through leakage of the damper to the area unit of duct cross section
α
- blade positioning angle [°]
[m
3
.h
-1
.m
-2
, l.s.m
-2
]
Product Ordering
In an order, it is necessary to indicate the following information:
Designation:
IMOS - XXX a x b - X - X
Non-Tight Regulating Damper
RK
Tight Regulating Damper
RKT
Width a
Height
b
Manual operation
R
Servomotor operation
S
Width of the duct or a flange P20
P1
P30
P2
An example of a Non-Tight Regulating Damper order a=450 mm, b=500 mm, manual operation:
IMOS - RK 450 x 500 - R - P1
An example of a Tight Regulating Damper order a=1120 mm, b=560 mm, servomotor operation:
IMOS - RKT 1120 x 560 - S - P2