It's only for fluid mechanics. Those are need to know about Darcy’s law & chezy’s law

1. By Group 1
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2.  Md.Ariful Islam--------10307044
 Nur-E-Alam Siddike---10307050
 Abu Bakar Siddique---10307076
 Mahadi Hasan Rubel---10307059
 Arfan Hossain ----------11170119
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3.  Know the formula
 Describe the formula
 Application of formula
 Importants of formula
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4. Major Losses
 losses due to friction
Minor Losses
 entrance and exit
 sudden change of cross sections
 valves and gates
 bends and elbows ect
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6. When the water is flowing in a pipe, it
experiences some resistance to its motion,
whose effect is the velocity and ultimately
the head of water available. An empirical
formula for the loss of head due to friction
was derived by Henry Darcy
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7. hf = Loss of head due to friction
L = Length of pipe
D= Diameter of the pipe
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8. 8

9.  Let,
l= length of the pipe
D= diameter of the pipe
v= Velocity of water in the pipe
f'= Frictional resistance per unit area at unit
velocity
Consider sections (1-1) and (2-2) of the pipe
Let,
p1= Intensity of pressure at section (1-1)
p2= Intensity of pressure at section (2-2)
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11.  Chézy was born at Chalon-
sur-Marne, France, on
September 1, 1718, and
died on October 4, 1798.
He retired in 1790 under
conditions of extreme
poverty. It was not until
1797, a year before his
death, that the efforts of
one of his former
students, Baron Riche de
Prony, finally resulted in
Chézy's belated
appointment as director of
the Ecole des Ponts et
Chaussées.
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12. Chezy Formula : Can be derived from basic
principles. It states that
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13.  V is velocity
 R is hydraulic radius
 S is slope of the channel
 C is Chezy coefficient and is a function of
hydraulic radius and channel roughness
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15.  Let,
l= length of the pipe
D= diameter of the pipe
v= Velocity of water in the pipe
f'= Frictional resistance per unit area at unit
velocity
Consider sections (1-1) and (2-2) of the pipe
Let,
p1= Intensity of pressure at section (1-1)
p2= Intensity of pressure at section (2-2)
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17. Figure from Hornberger et al. (1998)
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18. Figure from Hornberger et al. (1998)
Generalization of Darcy’s column
h/L = hydraulic
gradient
q = Q/A
Q is proportional
to h/L
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19. Figure from Hornberger et al. (1998)
Linear flow paths
assumed in Darcy’s
law
True flow paths
Average linear velocity
v = Q/An= q/n
n = effective porosity
Specific discharge
q = Q/A
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20. Inflow = Outflow
Recharge
Discharge
Steady State Water Balance Equation
Transient Water Balance Equation
Inflow = Outflow +/- Change in Storage
Outflow - Inflow = Change in Storage
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21.  Power generation
 Mining
 Refrigeration
 Vehicles
 Water supply drainage system etc.
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