Hydraulic Engineering

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Hydraulic Engineering

• Prof. Zaher Kuhail
• Eng. Tamer Eshtawi

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Lecture 12

• Water Pump

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Safety systems on pipelines to avoid (water
hummer)
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• Pump Inertia
• Bypass Reflex Valve
• Surge Tanks

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• Discharge Tanks
• Reflex Valve

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Water Pump

• Water pumps are devices designed to convert
  mechanical energy to hydraulic energy. They are
  used to move water from lower points to higher
  points with a required discharge and pressure
  head. This chapter will deal with the basic
  hydraulic concepts of water pumps.

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Hydraulic Analysis of Pumps and Piping Systems
Case 1
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• hs (static suction head) it is the difference in
  elevation between the suction liquid level and
  the centerline of the pump impeller.
• hd (static discharge head) it is the difference
  in elevation between the discharge liquid level
  and the centerline of the pump impeller.
• Hstat (static head) it is the difference (or
  sum) in elevation between the static discharge
  and the static suction heads, .
• Hms (manometric suction head) it is the suction
  gage reading (if a manometer is installed just at
  the inlet of the pump, then Hms is the height to
  which the water will rise in the manometer).
• Hmd (manometric discharge head) it is the
  discharge gage reading (if a manometer is
  installed just at the outlet of the pump, then
  Hmd is the height to which the water will rise in
  the manometer).
• Hm (manometric head) it is the increase of
  pressure head generated by the pump, .
• Ht (total dynamic head) it is the total head
  delivered by the pump

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Case 2
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Case 1
Case 2
Or From Bernoulli
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Pump Efficiency

• Which is the power input delivered from the motor
  to the pump

• Motor which has an the efficiency

which is the power input delivered to the motor.

• The overall efficiency of the motor-pump system

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Example 1
Pump with suction pipe diameter of 100mm and
delivery pipe diameter of 75mm, Q in the system
is 15L/s. the manometeric suction head is 198 mm
of mercury, where the manometeric discharge
pressure is 0.95 bar. Motor power is 3.2 KW
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Solution
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Efficiency