PULSAR MEASUREMENT 
 
91 
 
U-Throated Flume Calculations 
Absolute 
If the flow calculation is to be absolute P702 = 1 the flow will be calculated 
using the formula:  q = (2/3)
1.5
g
n
0.5
C
u
C
v
C
d
bh
1.5 
Where:   
q   = flowrate                 
g
n
 = gravitational acceleration, (nominal value = 980.66 cm/s
2
)   
h   = head           
C
u
= shape coefficient calculated by Ultra 4 (P724)                                                      
C
v
 = velocity coefficient calculated by Ultra 4 (P721)  
C
d 
= discharge coefficient calculated by Ultra 4 (P722)  
b   = throat width P711  
 
Ratiometric 
If the flow calculation is to be ratiometric P702 = 2 the flow will be 
calculated using the formula:   
q= q
cal
(C
v
/C
vcal
)(C
d
/C
dcal
)(C
u
/C
ucal
)(h/h
cal
)
1.5
 
Where:   
q = flowrate            
q 
cal 
= flowrate at maximum head P705       
Cv = velocity coefficient calculated by Ultra 4 (P721)  
Cv
cal
 = velocity coefficient at maximum head    
Cd = discharge coefficient calculated by Ultra 4 (P722) 
Cd
cal
 = discharge coefficient at maximum head  
Cu = shape coefficient P724                                            
Cu
cal
 = shape coefficient at maximum head          
h = head h
cal 
  = maximum head P704