Pumps & Turbines

PUMPS & TURBINES

Aashique Alam Rezwan

Lecturer

Dept. of Mechanical Engineering, BUET

http://teacher.buet.ac.bd/aashiquear

Pumps & Turbines

May 10, 2013 ME, BUET 2

Forces of Nature

HurricaneTsunami

Pumps & Turbines

Hydraulic

Energy

Kinetic Energy

Pressure

Energy

Potential

Energy

Thermal

Energy

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Pumps & Turbines

Hydraulic

Energy Kinetic Energy

Pressure

Energy

Potential

Energy

Thermal

Energy

May 10, 2013 ME, BUET 4

Pumps & Turbines

Hydraulic

Energy Kinetic Energy

Pressure

Energy

Potential

Energy

Thermal

Energy

May 10, 2013 ME, BUET 5

Pumps & Turbines

Hydraulic

Energy Kinetic Energy

Pressure

Energy

Potential

Energy

Thermal

Energy

May 10, 2013 ME, BUET 6

Pumps & Turbines

Hydraulic

Energy Kinetic Energy

Pressure

Energy

Potential

Energy

Thermal

Energy

May 10, 2013 ME, BUET 7

Pumps & Turbines

Turbo machines are

dynamic fluid

machines that either

extract energy from

a fluid (turbine) or

add energy to a fluid

(pump) as a result of

dynamic interactions

between the device

and the fluid.

Latin Turbo means to

spin or whirlMay 10, 2013 ME, BUET 8

Turbo Machinery

PUMP

Flow In Flow Out

TURBINE

Flow In Flow Out

Pumps & Turbines

Classifications of Turbo Machinery

May 10, 2013 ME, BUET 9

Turbo Machine

Turbine

Hydraulic

Steam

Vapor

Gas

Wind

Pump

Water

Slurry

Liquid

Compressor

Air

Gas

Blower

Air

Gas

Fan

Air

Gas

Pumps & Turbines

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Turbo Machinery

Pumps & Turbines

Axial Flow & Radial Flow Impeller

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Pumps & Turbines

Axial Flow Impeller

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Pumps & Turbines

Centrifugal Impeller

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Pumps & Turbines

Principles

of Turbo

Machinery Torque = Rate of change of angular momentum

Torque =

m(vw2r2-vw1r1)

Work Done =

m(vw2r2-vw1r1)

Work Done =

m(vw2u2-vw1u1)

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Pumps & Turbines

PUMPS

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Pumps & Turbines

Pump

A pump is a mechanical device which transfer energy from an external source to the liquid flowing through a conduit.

Mechanical Energy Hydraulic energy

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PUMP

Flow In Flow Out

16 Impeller

Impeller Casing

Motor

Casing

Armature Suction

Eye

Discharge

Pumps & Turbines

Example of Pumps in Nature

May 10, 2013 ME, BUET 17

Pumps & Turbines

Classification of Pumps

Pump

Positive Displacement

Rotodynamic

18 ME, BUET

Pumps & Turbines

Positive Displacement Pump

19 ME, BUET

Pumps & Turbines

Rotodynamic Pump

20 ME, BUET

Pumps & Turbines

Centrifugal Pump

21

, = 2

2

= 2

ME, BUET

Pumps & Turbines

Centrifugal Pump (contd.)

22 ME, BUET

Pumps & Turbines

Centrifugal

Pump

(contd.)

23 ME, BUET

Pumps & Turbines

Head of a Centrifugal Pump

24 ME, BUET

Pumps & Turbines

Losses in a Pump

25 ME, BUET

Pumps & Turbines

Density of air is about 800 times smaller than that of water

Obviously an impeller running in air would produce only a small head.

The first step in the operation of a centrifugal pump is to fill the pump with the liquid to be pumped.

This process is called the priming of the pump.

Priming is done by pouring liquid into the funnel provided for this purpose.

26

Priming

ME, BUET

Pumps & Turbines

Cavitation

27 ME, BUET

Pumps & Turbines

Cavitation (Contd.)

Cavitation is defined as the formation of bubbles and

vapour filled cavities in a flowing fluid as a result of

reduction in fluid pressure.

Vapour cavities are formed when the pressure at any

point in a flow field falls to the vapour pressure of the

liquid at that temperature.

28 ME, BUET

Pumps & Turbines

Effects of Cavitation

1. The normal flow pattern is changed as the cavitation

occurs. This disturbs the smooth flow.

2. The hydraulic machines indicate a sudden loss in

efficiency as soon as cavitation occurs.

3. As cavitation occurs, it may cause vibration. It may

further lead to fatigue stresses and excessive wear.

4. Cavitation is usually accompanied by noise.

5. The cavitating parts in the flow phenomenon cause an

increase in the drag force.

6. Some of the boundary material may be eaten away at

the points where cavitation occurs. It is known as

pitting.

29 ME, BUET

Pumps & Turbines

Multi-Stages

Pump

Pumps in

Series

H = n(H1+H2)

30

Pumps & Turbines

Multi-Stages

Pump

Pumps in

Parallel

Qt = nQ

31

Pumps & Turbines

TURBINES

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Pumps & Turbines

Turbines are devices

that convert the

energy of fluid into

mechanical energy.

Water potential or

kinetic energy.

Steam/Flue

thermal energy

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TURBINE

TURBINE

Flow In Flow Out

Pumps & Turbines

Classification of Turbines

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Turbines

Impulse Turbine Reaction Turbine

Pumps & Turbines

May 10, 2013 ME, BUET 35

Pelton Wheel

Pumps & Turbines

May 10, 2013 ME, BUET 36

Pelton Wheel (contd.)

Pumps & Turbines

May 10, 2013 ME, BUET 37

Kaplan Turbine

Pumps & Turbines

May 10, 2013 ME, BUET 38

Kaplan Turbine (contd.)

Pumps & Turbines

May 10, 2013 ME, BUET 39

Kaplan Turbine (contd.)

Pumps & Turbines

Hydroelectric Power Plant

May 10, 2013 ME, BUET 40

Pumps & Turbines

May 10, 2013 ME, BUET 41

Karnafuli Hydroelectric Power Plant

Generation capacity: 230 MW

Reservoir size: 777 sq. km

Pumps & Turbines

GAS TURBINE

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Pumps & Turbines

Gas Turbine Components

May 10, 2013 ME, BUET 43

Pumps & Turbines

Gas Turbine Components (contd.)

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Pumps & Turbines

JET ENGINE (Turbo Jet)

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Pumps & Turbines

Airfoil

May 10, 2013 ME, BUET 46

Pumps & Turbines

Forces on an Aero Plane

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Pumps & Turbines

Turbo Fan

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Pumps & Turbines

Turbo Prop

May 10, 2013 ME, BUET 49

Pumps & Turbines

Vertical Takeoff and Landing (VTOL)

May 10, 2013 ME, BUET 50

Pumps & Turbines

THANK YOU

May 10, 2013 ME, BUET 51