Siemens OCM III, Instruction Manual, Page: 61 / 112

BS-3680 TRAPEZOIDAL FLUME, P3 = 3
‘U’ parameters required * ‘U’ parameters calculated **
U0 = approach width B U5 = Cv
U1 = throat width b U6 = Cd
U2 = hump height p U7 = Cs
U3 = throat length L U8 = A
U4 = slope m
*obtain from manufacturer’s specifications.
**
calculated by OCM-3. May be viewed by accessing ‘U’ parameter.
Reference
ABSOLUTE CALCULATION, P4 = 0
¤
For flows that can be calculated by the equation:
q = (2/3)
1.5
x g
0.5
x Cv x Cs x Cd x b x h
1.5
where : q = flow rate Cv = velocity coefficient
g = gravitational acceleration Cs = shape coefficient
b = throat width Cd = discharge coefficient
h = head
RATIOMETRIC CALCULATION, P4 = 1
¤
For flows that can be calculated by the equation:
q = q
cal
x Cs/Cs
cal
x Cd/Cd
al
x Cv/Cv
cal
x (h/h
cal
)
1.5
where :
q = flow rate Cs
cal
= shape coefficient for maximum head
q
cal
= flow rate at maximum head Cv = velocity coefficient
h = head Cv
cal
= velocity coefficient for maximum head
h
cal
= maximum head Cd = discharge coefficient for head
Cs = shape coefficient for head Cd
cal
= discharge coefficient for maximum head
¤
Refer to Operation \ Flow Calculation.
7ML19985AB01 OCM III 62