5 v-notch, Calculation of the actual flow value (q), Selection of the actual flow (q) – VEGA VEGASON 71 - D User Manual
Page 30

VEGASON 71 - D
30
7.6.5 V-Notch
With sharp weir edge
K (Factor)
Calculation of the actual flow value (Q)
The following formula can be used for calculation of the
actual flow.
Q = K • h
2,5
α
in
°
Q in m
3
/h
h in m
Assumed values for a calculation example
α
=
45
°
K =
2056 (derived from
α
)
h =
0,33 m
Calculation example
Q =
2056 • 0,33
2,5
= 128,6 m
3
/h
Programming acc. to calculation example
Q
max
= 128,6 m
3
/h
-
Mode
0 - 82
, flow = 0129
-
Mode
0 - 83
, multiplier = 0
-
Mode
0 - 84
, time unit = 3
Explanation:
Q
max
= max. flow in m
3
/h
α
= angle of beam
K
= weir specific factor
h
max
= max. weir height in mm or m
k
= thickness of the weir in mm
7 Output results
h
max
2 - 3 x h
max
3 - 4 x h
max
Selection of the actual flow (Q)
Flow schedule for usual V-Notch
α
K
Q
max
h
max
Q
min
h
min
in
°
(Factor)
in m
3
/h
in mm
in m
3
/h
in mm
90
4966
1385,0
600
4,4
60
60
2869
800,0
600
2,5
60
45
2056
573,3
600
1,8
60
30
1334
372,0
600
1,2
60
22,5
989
275,8
600
0,87
60
If a V-Notch acc. to above value is used, the value for Q
max
can be taken out of the respective column and can be
used for programming of mode
0 - 82
…
0 - 84
.
Programming acc. to selection Q
max
= 573,3 m
3
/h
- Mode
0 - 82
, flow = 0573
- Mode
0 - 83
, multiplier = 0
- Mode
0 - 84
, time unit = 3
k
≈
3 mm
45
°
k
≈
3 mm
≥
2 x h
max
α
or