OUTDOOR LOUVER GRILL 210 TA INSTRUCTION

Technical data 210-TA
Series 100-200
11
Selection example
Next, a selection example is shown in order to pre
-select the specific dimensions of an air intake or extract grille.
The starting point is the design flow rate, for example, 3000 m
3
/h. First of all, the frontal area required to give a face velocity
of around 2.5 m/s is calculated, i.e.
(3000m
3
/h)/(3600s/h) = 2.5 m/s*A
frontal
(m
2
) ; A
frontal
(m
2
)=0.333
The dimensio
ns are found using the formula in the “Quick selection table” section (L-0,014)x(H-
0,109), and according to the
desired aspect ratio. In this example we will use 2:1. The frontal length will therefore be 0.816 m and the frontal height
approximately 0.408
m.
We would therefore choose an intake with approximate dimensions LxH of 0.82 m x 0.517 m.
The height should be rounded to the nearest 50 mm increment and we should also round the length accordingly, which
would give dimensions LxH of 0.85 m x 0.5 m.
The frontal velocity that corresponds to these dimensions according to the frontal area calculated in the “Quick selection
table” section would be:
A
f
(m
2
)= (0.85-0,014)x(0.5-0,109)=0.3268 m
2
(
3000m
3
/h)/(3600s/h)= V
frontal
(m/s)*0.3268 m
2
; V
frontal
(m/s)=2.5 m/s
The pressure loss is obtained directly from graphs 1 and 2. In this case:
Pressure loss with anti
-bird mesh = 30 Pa when used for air extract (graph 2) and 28 Pa for intake (graph 1).
The sound power level is obtained from graph 3 and subsequently corrected for area in accordance with table 3.
In this case:
Noise level = (51
-5)=46 dB(A) when used as an intake and (48-5)=43 dB(A) as an extract.