Siemens 7ML19985AB01 Benutzerhandbuch

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BS-3680 U-Flume,  P3 = 4
‘U’ parameters required *
‘U’ parameters calculated **
U0 = approach diameter 
Da
U4 = Cv
U1 = throat diameter 
D
U5 = Cd
U2 = hump height 
p
U6 = Cu
U3 = throat length 
L
U7 = A
*
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 Cu x Cd x D x h
1.5
where :  q = flow rate
Cv = velocity coefficient
g = gravitational acceleration
Cu = 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 Cu/Cu
cal
 x Cd/Cd
cal
 x Cv/Cv
cal
 x (h/h
cal
)
1.5
where :
q = flow rate
q
cal
 = flow rate at maximum head
h = head
h
cal
 = maximum head
Cu = shape coefficient for head
Cu
cal
 = shape coefficient for maximum head
Cv = velocity coefficient
Cv
cal
 = velocity coefficient for maximum head
Cd = discharge coefficient for head
Cd
cal
 = discharge coefficient for maximum head
¤
 Refer to Operation \ Flow Calculation.
7ML19985AB01
OCM III
64