Centrifugal pumps have two main components - a rotating impeller and shaft, and a stationary casing and bearings. Centrifugal pumps work by converting the rotational kinetic energy of the impeller into pressure energy of the fluid. Auxiliary components include seal drains, bearings lubrication systems, and piping. The working mechanism involves an impeller imparting kinetic energy to the fluid which is then converted to pressure energy to lift the fluid to the desired discharge point. Important terms are capacity (flow rate), head (pressure/lift), efficiency (ratio of pump output to input), best efficiency point (where efficiency is highest), and specific speed (measure of geometric pump similarity).

1. Centrifugal Pumps
PRESENTED BY
˃ SHEHR YAAR ABDULLAH ˃ROLL NO 17CE’23
DEPARTMENT OF CIVIL ENGINEERING
BALUCHISTAN UET, KHUZDAR
Subject:
Advance Fluid Mechanics
Point On Question ։-
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2. • 2000 BC Egyptians invent the shadoof
to raise water. It uses a long suspended
rod with a bucket at one end and a
weight at the other.
History Of Centrifugal Pumps; 2
A Typical Shadoof of Epyptians
Denis Papin developed the first true
centrifugal pump in 1687, which was
one with straight vanes that was used
for drainage.
John Appold, who was a British
inventor, developed the first curved
vane centrifugal pump in 1851

3. Centrifugal Pumps?
General Components of Centrifugal Pumps:
A centrifugal pump has two main components:
1. A rotating component comprised of an impeller and a shaft
2. II. A stationary component comprised of a casing, casing cover, and bearings.
Basic Definition: Centrifugal pumps are
used to transport fluids by the conversion
of rotational kinetic energy to the
pressure energy of the fluid flow.
General components of Centrifugal Pump
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4. Centrifugal Pumps?
Auxiliary Components:
Auxiliary piping systems include tubing, piping, isolating valves, control valves, relief valves,
temperature gauges and thermocouples, pressure gauges, sight flow indicators, orifices and all
related vents and drains.
Auxiliary components generally include the following piping systems for the following services:
1. Seal drains and vents.
2. Bearing lubrication , cooling systems.
3. Seal chamber or stuffing box cooling, heating systems.
4. Pump cooling systems.
 Note: All auxiliary
components shall comply
with the requirements as
per standard codes like
API 610, API 682 etc
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5. Operational Error:
The fact of the matter is that there are three types of problems mostly
encountered with centrifugal pumps:
1. Design errors.
2. Poor operation.
3. Poor maintenance practices.
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6. Centrifugal Pumps?
Working Mechanism of a Centrifugal Pump:
A centrifugal pump is one of the simplest pieces of equipment
in any process plant.
 A pump that moves water or other fluids to a
desired head.
Prime Mover
Kinetic energy
Pressure Energy
Liquid flow path inside a centrifugal pump
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7. Definition of Important Terms:7
01
02
03
04
Capacity Head
Efficiency Specific
speed.

8. 8
 1.Capacity: Flow rate with which liquid is moved or pushed by the pump to the desired
point.
Formula Expression:
Q= 𝟒𝟒𝟗 × 𝑽 × 𝑨
It is commonly measured in
a. Gallons per minute (g /m)
b. Cubic meters per hour (m3 /hr).
 2.Head: (Significantly “head” term is used instead of the “pressure” term)
Head is a measurement of the height of a liquid column that the pump could create
from the kinetic energy imparted to the liquid.
1. Static Suction Head, hS 2. Static Discharge Head, hd
3. Friction Head, hf 4. Vapor pressure Head, hvp
5. Pressure Head, hp 6. Velocity Head, hv
Where
449= Constant
Q= Capacity in gallons per
minutes (GPM)
V= Velocity of the flow
ft/sec
A= Area of the pipe 𝒇𝒕 𝟐
 The green line is indicating the pump
centerline.

9. 9
 3.Efficiency: η
 Pump efficiency is the ratio pump output and pump input.
OR
 Pump efficiency is the ratio of water horse-power (WHP) and
brake horse-power (BHP)
Formula Expression:
 Best Efficiency Point (BEP):
It is the capacity at maximum impeller diameter at which the efficiency is
highest.
Measuring the BEP:
1. Energy conversion
2. Mechanically stable operation
P𝒖𝒎𝒑 𝑬𝒇𝒇𝒊𝒄𝒊𝒆𝒏𝒄𝒚 𝑬𝒇𝒇. η =
𝑷𝒖𝒎𝒑 𝒐𝒖𝒕𝒑𝒖𝒕
𝒑𝒖𝒎𝒑 𝒊𝒏𝒑𝒖𝒕
=
𝑾𝑯𝑷
𝑩𝑯𝑷
= %

10. 10
 4.Specific Speed: Ns
 A measure of the geometric similarity of pumps.
 Specific speed is a non-dimensional design index that
identifies the geometric similarity of pumps
 Application of Specific Speed:
It is used to classify pump impellers as to their type. Pumps of the same Ns but of
different size are considered to be geometrically similar
 Specific speed Calculation
The following formula is used to determine specific speed:
𝑺𝒑𝒆𝒄𝒊𝒇𝒊𝒄 𝑺𝒑𝒆𝒆𝒅 ; 𝑵𝒔 =
𝑵 × 𝑸 𝟎.𝟓
𝑯 𝟎.𝟕𝟓
Where,
N= Pump Speed, RPM.
Q= Capacity at best efficiency (BEP) at max.
impeller diameter, GPM.
H= Head per stage at BEP at max. impeller
diameter, ft.

11. Thankyou for listening  11