Page 105 - ebook fluid mechanics_finalize
P. 105
FLUID MECHANICS
ii. Coefficient of Velocity, Cv
x
h
A y
B
Figure 4.14 : Orifice
From Figure 4.14 ,
t
x = horizontal falls = velocity time = v
1 1
y = vertical falls = gravity time = g
2
t
2 2
h = head of liquid above the orifice
v
= Coefficient of Velocity = C =
Cv v
2 gH
t = time for particle to travel from vena contracta A to point B
Actual velocity at vena contacta
Coefficient of Velocity, Cv =
Theoretica l velocity
v
C =
v
2 gH
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