Armfield C4-MKII, Инструкция по эксплуатации

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33
Theory
For a rectangular sharp crested weir:
Q =
2
3
d
y 2g b C
3
2
c
therefore: C
d
=
2
3
y 2g b
3
2
Q
c
where:
Q = Volume flowrate (m
3
.s
-1
)
= Volume/time (using volumetric tank)
C
d
= Coefficient of discharge (Dimensionless)
b = Breadth of weir (m)
y
c
= Height above crest of weir (upstream)
= y
0
- h
(m)
g = Gravitational constant (9.81ms
-2
)
h = Height of weir crest above bed (m)
y
0
= Upstream flow depth (m)
When the rectangular weir extends across the whole width of the channel it is called a suppressed
weir and the Rehbock formula can be applied to determine C
d
as follows:
h
y
0.083 0.602 C
c
d
⋅ + =