Page 92 - ebook fluid mechanics_finalize

FLUID MECHANICS

Where Cd = coefficient of discharge.

Considering the U-tube gauge and assuming that the connections are filled with

the liquid in the pipe line, pressures at level PQ are the same in both limbs,

For left limb,

p = p + w (z − ) y
z
2
1
For right limb,

)
p = p + ( z − y − x + w g x
2
z
2
Thus,

Pressure for left limb = Pressure for right limb

)
p 2 + ( − yz 1 ) = p + ( z − y − x + w g x
2
2

p 2 + z 1 − z 2 = p + z − y − x + w g x \
2
2

p − p  g 
1 2 + z − z =  x  −1 

 1 2   

Equation (2) can therefore be written

C A   g  
Q actual = d 1  2gx  −1  



(m 2 −1 )      

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