applied thermal engineering

102013 Basic Mechanical Engineering A J Bhosale

AISSMS College of Engineering, Pune

Unit 6:

Applied Thermal Engineering

Presented by,

Arvind J Bhosale

Asst. Prof.

Mechanical Engineering

AISSMS CoE, Pune



Syllabus:

Power Plant Engineering: Conventional and non-conventional

energy sources, Hydro-electric, Thermal, Nuclear, Wind,

Solar (with block diagram)

Power Producing Devices: Boiler- Water tube and Fire tube,

Internal Combustion Engines – Two stroke and four stroke

(spark ignition and compression ignition), Turbines – Impulse

& Reaction

Power Absorbing Devices: Pump – Reciprocating &

Centrifugal, Compressors – Single acting, Single stage

reciprocating air compressor, Refrigerator – Vapor

compression refrigeration process, House hold refrigerator,

Window air conditioner (working with block diagram)



POWER PRODUCING DEVICES:- Turbines (Impulse & Reaction)

Internal Combustion Engines (Two stroke & Four stroke (CI & SI))

Boiler- Water Tube Boiler & Fire Tube Boiler

POWER ABSORBING DEVICES:- Pump (Centrifugal & Reciprocating)

Compressor(Reciprocating – single stage, single acting)

Refrigerator (House hold)

Window Air Conditioner

POWER PLANT ENGINEERING:- Thermal Power Plant

Hydro- Electric Power Plant

Nuclear Power Plant

Wind Power Plant

Solar Power Plant



Boiler

A boiler is a closed vessel in which steam is produced from

water by combustion of fuel.

Purposes of Steam:

For generating power in steam engines or steam turbines.

In Sugar Mill, Chemical & many more.

For heating the buildings in cold weather and for producing hot water for

hot water supply.

Primary requirement of Steam:

The water must be contained safely.

The steam must be safely delivered in desired conditions (as regards its

pressure, temperature , quality and required rates).



Simple Boiler



Steam:

• Steam is vapourized water. It is a transparent gas. At

standard temperature and pressure, pure steam (unmixed

with air, but in equilibrium with liquid water) occupies about

1,600 times the volume of an equal mass of liquid water.

• Saturated steam is steam at equilibrium with liquid water at

the same pressure and temperature.

• Superheated steam is steam at a temperature higher than

its boiling point at a given pressure



Boiler Requirements:

• Safety

– The boiler should be safe under operating conditions.

• Accessibility

– The various parts of the boiler should be accessible for repair andmaintenance.

• Capacity

– Should be capable of supplying steam according to the requirements.

• Efficiency

– Should be able to absorb a maximum amount of heat produced due toburning of fuel in the furnace.

• Construction

– simple in construction .

• Cost

– Its initial cost and maintenance cost should below.



Classification of Boilers:

1. Depending upon the relative position of Water and Flue gases:

Water Tube Boiler

Smoke or Fire Tube Boiler

2. Depending upon the Position Furnace:

Internally Fired Boiler

Externally Fired Boiler

3. Depending upon the Position of Axis of the Boiler:

Vertical Boiler

Horizontal Boiler

4. Depending upon the Service:

Stationary Boiler

Portable Boiler



5. According to the Method of Circulation of Water and Steam:

Natural Circulation

Forced Circulation

6. According to the Pressure of Steam Generated:

Low Pressure (pressure of steam below 20 bar)

Medium Pressure( pressure of steam in range of 20-80 bar)

High Pressure (80 bar &above pressure of steam )

7. According to Nature of Draught Employed

Natural or Chimney Draught

Artificial Draught



Water Tube Boiler :

• In these, the water flows in the

tube and hot gases are passed

over the tubes.

• These type of boilers are useful

for large amount of steam

generation at high pressures due

to low water to high flue gases

ratio.

• Used for high steam demand

and pressure requirements

• Capacity range of 4,500 –

120,000 kg/hour

• Combustion efficiency enhanced

by induced draft provisions

• Lower tolerance for water quality

and needs water treatment plant



Babcock and Wilcox Boiler:

• D- Drum

• DTH- Down take header

• WT- Water Tubes

• BP- Baffle Plates

• D- Doors

• G- Grate

• FD-Fire Door

• MC- Mud Collector

• WLI- Water Level Indicator

• PG- Pressure Gauge

• ST- Super heater Tubes

• SV- Safety Valve

• MSV- Main Stop Valve

• APP- Anti priming Pipe

• L- Lower Junction Box

• FV- Feed Valve



• This is the one of the most important type of water tube boiler as shownin above figure.

• It consists of number of inclined water tubes connected between uptakeheader and downtake header.

• Whole combustion chamber is divided into number of parts with the helpof baffles so that hot gases first move from the furnace upwardsbetween the water tubes and then move downward and upward betweenthe baffles over the tubes and finally these are exhausted to the chimneythrough the damper.

• The water near the uptake header are in contact with the hotter flue gasescompared to portion near the downtake header due to which the water inthe uptake header rises due to decreased density and enters the drumwhich is replaced by the cold water from the downtake header.

• Wet steam from the boiler drum enters in the outer tube, then passes intothe superheated tubes and during its passage it gets further heated up.Superheated steam now enters into the inner tubes and from here it iswithdrawn through a stop valve.



Lamont Boiler :



Fire Tube Boiler :

• In these boilers, the flue

gases pass through the

tubes which are

surrounded by water in

boiler shell.

• Relatively small steam

capacities (12,000

kg/hour)

• Low to medium steam

pressures (18 kg/cm2)

• Operates with oil, gas or

solid fuels



Cochran Boiler:

Salient features• The dome shape of the furnacecauses the hot gases to deflectback and pass through the fluepipe. The un‐burnt fuel if any willalso be deflected back.• Spherical shape of the top of theshell and the fire box gives higherarea by volume ratio.• It occupies comparatively lessfloor area and is very compact.• It is well suited for small capacityrequirements.



Cochran Boiler

• Very compact and requires

minimum floor area

• Any type of fuel can be

used with this boiler

• Well suited for small

capacity requirements

• Gives about 70% thermal

efficiency with coal firing and

about 75% with oil firing



Lancashire Boiler



• It is stationary, fire tube, internally fired, horizontal,

natural circulation boiler.

• This is a widely used boiler because of its good steaming

quality and its ability to burn coal of inferior quality.

• These boilers have a cylindrical shell 2 m in diameters

and its length varies from 8 m to 10 m.

• It has two large internal flue tubes having diameter

between 80 cm to 100 cm in which the grate is situated.

• This boiler is set in brickwork forming external flue so

that the external part of the shell forms part of the

heating surface.



Boiler Mountings:- Stop valve

Safety Valve

Water Level Indicators

Pressure Gauge

Fusible Plug

Blow Off Cock, etc.

Boiler Accessories:- Economizers

Super heaters

Air -Preheater

Feed Pumps, etc.



Difference between Water Tube And Fire Tube Boiler:

SrNo

Factors Water Tube Boiler Fire Tube Boiler

1 Position of waterand flue gases

Water flows inside tubesand flue gases arecirculated around thetubes

Flue gases are insidethe tubes and water iscirculated around thetubes

2 Floor area for thesame power

It occupies less floor area It occupies more floorarea

3 Rate of steamgeneration

Higher Lesser

4 Construction Simple Difficult

5 Transportation Simpler Difficult



.SrNo


6 Shell diameter for thegiven power

Less required Large

7 Treatment of water Not so much necessary More necessary

8 Requirement of skill It requires more skill aswell as careful attention

It requires less skill forefficient and economicworking

9 Accessibility ofvarious parts forcleaning, repair andinspection

It has more accessibility The parts are not soeasily accessible

10 Suitability Suitable Not suitable for largepower generation.



.

SrNo


11 Risk of bursting More (Steam Pressure) Less

12 Operating Pressure High Pressure (100bar) Less Pressure (16bar)



Steam Turbines:

A steam turbine is a thermo-mechanical device that extracts

thermal energy from pressurized steam, and converts it

into rotary motion.



Classification of Turbines

Turbines

Steam Turbines

Impulse Turbines

Reaction Turbines

Hydraulic Turbines

Impulse-Pelton Turbines

Reaction-Kaplan Turbines

Reaction-Francis Turbines

Gas Turbines

Open Cycle Gas Turbines

Closed Cycle Gas Turbines



Impulse Turbines:• An impulse turbine has fixednozzles that orient the steam flowinto high speed jets.

• These jets contain significantkinetic energy, which the rotorblades, shaped like buckets,convert into shaft rotation as thesteam jet changes direction.

• A pressure drop occurs acrossonly the stationary blades, with anet increase

Disadvantages:1. velocity of the wheel is too, high

(25000 to 30000 r p m.) for practical

purposes.

2. loss of kinetic energy. In an actual

turbine this loss is 10% to 12%.



Reaction Turbine:

• In the reaction turbine, the rotor blades themselves are arranged toform convergent nozzles.

• This type of turbine also makes use of the reaction force producedas the steam accelerates through the nozzles formed by the rotor.

• Steam is directed onto the rotor by the fixed vanes of the stator. Itleaves the stator as a jet that fills the entire circumference of therotor.

• The steam then changes direction and increases its speed relativeto the speed of the blades.

• A pressure drop occurs across both the stator and the rotor, withsteam accelerating through the stator and decelerating through therotor, with no net change in steam velocity across the stage butwith a decrease in both pressure and temperature, reflecting thework performed in the driving of the rotor.



In Reaction Turbines, the rotation is mainly achieved by the reaction

forces created by the acceleration of the fluid in the runner (rotating

blade). The basic principle is the same as a rotating lawn sprinkler in

which water enters the arms of the sprinkler at low velocity and leaves

through the jets at high velocity.

Newton's third law describes the transfer of energy for reactionturbines.

A Simple Reaction Turbine Actual Reaction Turbine



Animation



Hydraulic Turbines:

Hydraulic turbine – A rotary engine that converts hydraulic

energy into mechanical energy.

Mechanical energy is used in running an electric generator

which is coupled to turbine shaft.



Impulse Turbine:

• Energy available at the inlet of the turbine is only kinetic

energy.

• Pressure is atmospheric from inlet to outlet.

• Works on the basis of impulse momentum principle

• Eg: Pelton Wheel



Pelton Turbine:



Pelton Wheel:



Pelton Wheel:

• Water from reservoir flows through penstocks.

• At the outlet of penstock nozzle is fitted.

• Nozzle converts hydraulic energy of water into kinetic

energy.

• Water striking the nozzle is controlled using a spear.

• Water comes out as a jet from nozzle and strikes the

buckets (vanes) which are fixed on the periphery of a

wheel.

• Casing is used to prevent splashing of water.



Reaction Turbine:

• Energy of fluid partly transferred into kinetic energybefore it enters the runner

• It enters the runner with excess pressure.

• Pressure energy is converted into kinetic energy as waterpasses through runner.

• The difference in pressure between inlet and outlet ofrunner (reaction pressure) is responsible for motion ofrunner.

• Eg: Francis turbine, Kaplan Turbine



Francis Turbine:

• Named after American Engineer J.B.Francis

• It is a mixed flow reaction turbine with medium head and

medium specific speed



Francis Turbine Components:

• Penstock

• Scroll/Spiral casing

• Speed ring/Stay ring

• Stay vanes

• Guide vanes/Wicket vanes

• Runner blades

• Draft tube



Francis Turbine Working:

• Water from the penstock enters the scroll casing which

completely surrounds the runner.

• Involute casing provides an even distribution of

water(constant velocity) around the circumference of the

runner.

• Stay rings directs water from scroll casing to guide

vanes.



Francis Turbine Working:

• The guide vanes

-regulate the quantity of water supplied to the runner(totake care of the load variations)

-direct water to the runner at an appropriate angle.

• The runner consists of a series of curved vanes evenlyarranged around the circumference.

• At the entrance to the runner only a part of energy ofwater is converted into kinetic energy and substantialpart remains in the form of pressure energy.

• As water flows through the runner the change frompressure to kinetic energy takes place gradually.



Francis Turbine:

• The difference in pressure between the inlet and outlet of the

runner is called reaction pressure.

• Water enters the runner from the guide vanes towards the

centre radially and discharges out axially- Mixed flow

turbine.

• After doing work water is discharged to the tail race through

a closed tube of gradually enlarging section called draft tube.



Kaplan Turbine:

• Developed by Austrian Engineer V. Kaplan.

• Suitable for relatively low heads and requires large

volume of water to develop large power.

• Kaplan turbine is a reaction turbine in which water enters

and leaves the runner blades axially-Axial flow turbine



Kaplan Turbine Components:

Scroll casing

Guide Vanes

Runner Vanes

Draft tube



Kaplan Turbine Working:

• Kaplan turbine works on the reaction principle as Francis

turbine.

• Only difference is that water enters and leaves the turbine

axially –Axial flow turbine.

• Both the guide vane(wicket gate) angle and runner vane

angle can be adjusted which gives rise to high efficiency.



Selection of Turbine:

Type of turbine Range of head

Pelton 200-2000

Francis 15-300

Kaplan 5-30



Heat Engines

Any type of engine or machine which derives Heat Energy from the combustion of the

fuel or any other source and converts this energy into Mechanical Work is known as a

Heat Engine.

Classification :

1. External Combustion Engine (E. C. Engine) :

Combustion of fuel takes place outside the cylinder.

e.g. Steam Turbine, Gas Turbine Steam Engine, etc.



Heat EnginesAdvantages of External Combustion Engines over Internal Combustion Engines :

1. Starting Torque is generally high.

2. Due to external combustion, cheaper fuels can be used (even solid fuels !).

3. Due to external combustion, flexibility in arrangement is possible .

4. Self – Starting units.

Internal Combustion Engines require additional unit for starting the engine !

Advantages of Internal Combustion Engines over External Combustion Engines :

1. Overall efficiency is high.

2. Greater mechanical simplicity.

3. Weight – to – Power ratio is low.

4. Easy Starting in cold conditions.

5. Compact and require less space.



Classification of I. C. Engines

A. Cycle of Operation :

B. Cycle of Combustion :

2. Four – Stroke Engine1. Two – Stroke Engine.

1. Otto Cycle (Combustion at Constant Volume).

2. Diesel Cycle (Combustion at Constant Pressure).

3. Dual Cycle (Combustion partly at Constant Volume + Constant Pressure).




C. Arrangement of Cylinder :

1. Horizontal Engine. 2. Vertical Engine

3. V – type Engine 4. Radial Engine




D. Uses :

1. Automobile Engine. 2. Marine Engine

3. Stationary Engine 4. Portable Engine




E. Fuel used :

1. Oil Engine. 2. Petrol Engine

3. Gas Engine 4. Kerosene Engine

F. Speed of Engine :

1. High Speed 2. Low Speed

G. Method of Cooling :

1. Air – Cooled Engine. 2. Water – Cooled Engine




G. Method of Ignition :

2. Compression – Ignition (C.I.) Engine1. Spark – Ignition (S.I.) Engine.




I. No. of cylinders :

1. Single Cylinder Engine. 2. Multi - Cylinder Engine



Application of I. C. Engines

APPLICATIONS

Road vehicles. Aircrafts.

Locomotives.

Construction EquipmentsPumping Sets

Generators for Hospitals, Cinema Hall, and Public Places.



Air – Standard Cycles

OPERATING Cycle of an I. C. Engine ≡ Sequence of separate Processes.

1. Intake

2. Compression

3. Combustion

4. Expansion

5. Exhaust

I.C. Engine DOES NOT operate on a Thermodynamic Cycle, as it is an Open System.

i.e. Working Fluid enters the System at 1 set of conditions (State 1) and leaves at another

(State 2).

Compression ratio:



Otto Cycle

Basis of Spark – Ignition Engines.

0 -1 : Suction

1 -2 : Isentropic Compression

2 -3 : Constant Vol. Heat Addition

3 -4 : Isentropic Expansion

1 -0 : Exhaust

0 1

Pre

ssu

re, P

Volume, V

Isentropic

2

Qs

3

4

QR

Qs

1

2

Tem

per

atu

re, T

Entropy, s

3Isochoric

4

QR

4 -1 : Constant Vol.Heat Rejection



Diesel Cycle

Basis of Compression – Ignition Engines.

0 -1 : Suction

1 -2 : Isentropic Compression

2 -3 : Constant Pr. Heat Addition

3 -4 : Isentropic Expansion

1 -0 : Exhaust

Qs

1

2

Tem

per

atu

re, T

Entropy, s

3

Isobaric

4

QR

4 -1 : Constant Vol.Heat Rejection

0 1

Pre

ssu

re, P

Volume, V

Isentropic2

Qs 3

4

QR

Isochoric



Cylinder

Piston

Combustion chamber

Inlet manifold

Exhaust manifold

Connecting rod

Crankshaft

Valve trains

Basic Components of IC Engine



Four Stroke S.I. Engine



Four – Stroke / Compression Ignition (C.I.) Engine



Two Stroke I C Engine



Two – Stroke / Spark Ignition (S.I.) Engine



Comparison : Two – Stroke Vs. Four Stroke

Sr.

No.

Description Four Stroke Engines Two Stoke Engines

1 Completion of

cycle

Cycle is completed in four

strokes of the piston or in two

revolutions of the crankshaft.

Cycle is completed in two

strokes of the piston or one

revolution of the

crankshaft.

2 Power produced

for same cylinder

dimensions and

speed

Less High

3 Size of flywheel Heavier flywheel is needed Lighter flywheel is needed

4 Initial cost and

space requirement

for same size of

engine

Occupies more space and

costly.

Occupies less space and

cheaper.



5 Thermal

efficiency

High Low

6 Volumetric

efficiency

High due to more time

for induction

Low due to less time of

induction.

7 Starting Complicated Easy

8 Noise Less High

9 Application Used where efficiency is

important, viz., in Cars,

Buses Trucks, Tractors,

Aero planes Industrial

engines, Generators etc.

Used where low cost,

compactness and light weight

are important viz., in

mopeds, scooters,

motorcycles, etc.

Comparison : Two – Stroke Vs. Four Stroke



Comparison : S.I. Vs. C.I. Engines

Sr.

No.

Description SI Engines CI Engines

1 Basic cycle Based on Otto cycle Based on Diesel cycle

2 Fuel used Gasoline (Petrol) having high

self ignition temperature

Diesel having lower self ignition

temperature compared to

gasoline

3 Induction A carburetor is used to prepare

the required strength of

mixture of fuel and air

No carburetor is needed. Fuel is

injected with the help of fuel

pump under high pressure

directly into combustion

chamber

4 Compression

ratio (CR)

Varies from 6-10 Varies from 16-20

5 Ignition Spark is used to ignite the

mixture

The self ignition of fuel occurs

due to high temperature of air

because of high compression of

air



Comparison : S.I. Vs. C.I. Engines

6 Speed High speed engines due to

light weight

Low speed engine due to

heavy weight

7 Thermal

Efficiency

Low efficiency due to low

CR

High efficiency because

of higher CR

8 Starting Easy due to low CR Difficult due to high CR

9 Running cost More as they use costly

fuel

Low as they use cheap

fuel

10 Initial cost Low High



Comparison : Petrol Vs. Diesel Engines

Sr. No. Petrol Engine Diesel Engine

1. Working : Otto Cycle Working : Diesel Cycle

2. Suction Stroke :Air / Fuel mixture is taken in

Suction Stroke :only Air is taken in

3. Spark Plug Fuel Injector

4. Spark Ignition generates Power Compression Ignition generates Power

5. Thermal Efficiency – 35 % Thermal Efficiency – 40 %

6. Compact Bulky

7. Running Cost – High Running Cost – Low

8. Light – Weight Heavy – Weight

9. Fuel : Costly Fuel : Cheaper

10. Gasoline : Volatile and Danger Diesel : Non-volatile and Safe.

11. Less Dependable More Dependable



Power Absorbing Devices:-

Compressor

Pumps

Refrigerator

Air Conditioner



Compressor:-

COMPRESSOR – A device which takes a definite

quantity of fluid ( usually gas, and most often air ) and

deliver it at a required pressure.

Air Compressor- are used to compress the atmospheric

air to high pressure.

Air Compressor –1) Takes in atmospheric air,

2) Compresses it, and

3) Delivers it to a storage vessel ( i.e. Reservoir ).



Uses of Compressed Air:

Inflating tyres /tubes

In spray Paintings

For cleaning purposes in garages along with water for washing

cars etc.

Gas turbines

Diesel Engines

Air Brakes



Uses of Compressed Air

Compressed Air

Powering portable small Engines

Drills and Hammers in road building

Excavating

Tunneling and MiningStarting the

Diesel engines

Operating Brakes for buses, trucks and trains



Classification

Air Compressors

Reciprocating Rotary

Single – actingDouble - Acting

No. of Sides of Piston in operation

No. of Stages for Compression

Centrifugal

Single – stageMulti - stage



Reciprocating Compressor - Working



Reciprocating Compressor - Working

ME0223 SEM-IV Applied Thermodynamics & Heat Engines



• Single acting Single stage Reciprocating Compressor

Working Principle:

Block diagram of Single acting Single stage Reciprocating Compressor



Refrigeration

REFRIGERATION – Science of producing and maintaining temperature below that of

surrounding / atmosphere.

REFRIGERATION – Cooling of or removal of heat from a system.

Refrigerating System – Equipment employed to maintain the system at a low temperature.

Refrigerated System – System which is kept at lower temperature.

Refrigeration – 1) By melting of a solid,

2) By sublimation of a solid,

3) By evaporation of a liquid.

Most of the commercial refrigeration production : Evaporation of liquid.

This liquid is known as Refrigerant.



Refrigeration Circuit

Refrigeration Circuit

EvaporatorCompressor

CondenserExpansion Valve



Refrigeration - Elements

Compressor

Condenser

Evaporator

Expansion Valve

Wnet, in

Surrounding Air

Refrigerated Space

QH

QL

High Temp Source

Low TempSink

QH

QL

Wnet, in



Vapor Compression Cycle:-



Refrigeration - Applications1. Ice making.

2. Transportation of food items above and below freezing.

2. Industrial Air – Conditioning.

4. Comfort Air – Conditioning.

5. Chemical and related industries.

6. Medical and Surgical instruments.

7. Processing food products and beverages.

8. Oil Refining.

9. Synthetic Rubber Manufacturing.

10. Manufacture and treatment of metals.

11. Freezing food products.

12. Manufacturing Solid Carbon Dioxide.

13. Production of extremely low temperatures (Cryogenics)

14. Plumbing.

15. Building Construction.

Applications :



Window Air Conditioner:

Air conditioning is the simultaneous control of temperature,humidity, motion, and purity of atmosphere of confinedspace.

Application of Air conditioning:-

Industrial applications Food Industry

Photographic Industry

Printing Industry

Hospital Air conditioning

Transport Air conditioning Automobile Air conditioning

Train Air conditioning

Air craft Air conditioning

Ship Air conditioning

Air conditioning of Computer centers

Air conditioning of television centers



Block diagram of Window Air conditioner



Sources of Energy:

Conventional Energy

Sources

Coal

Water

Nuclear Energy

Petroleum Products

Natural gas

Non-Conventional

Energy Sources

Solar

Wind

Ocean

Tidal

Geo-Thermal, etc



Non-Conventional Energy Sources:

ADVANTAGES

Easily available in nature.

Available in large quantity.

Not pollutant.

Less maintenance cost.

Sources

Solar

Wind

Ocean

Tidal

Geo-Thermal, etc DIS-ADVANTAGES

Available in Low intensity.

Available in particular period only.

Less efficiency of power plant.

High initial cost.



Conventional Energy Sources

ADVANTAGES

Thermal Efficiency is more

Initial cost is less.

Intensities are high.

Sources

Coal

Water

Nuclear Energy

Petroleum Products

Natural gasDIS-ADVANTAGES

Running and maintenance cost is high

Pollution in atmosphere.



Power Plants:

• Thermal/ Steam Power plants

• Hydroelectric Power Plant

• Solar Power System

• Wind Power Plant



Thermal Power Plant:

Thermal power is the largest source of power in India. About 75% of electricity

consumed in India are generated by Thermal power plants. There are different

types of Thermal power plants based on the fuel used to generate the steam such

as coal, gas, diesel etc.

Coal-fired plants account for 56% of India's installed electricity capacity.

The thermal energy available in the steam is converted into mechanical energy

and is used for driving steam turbines. Steam turbines is coupled to generator

and hence power is produced whenever turbine is rotated.



Prime factors for starting a steam power plant

– Availability of fuel, Coal

– Availability of water

– Availability of strong foil foundation

– Availability of transport facility

– Availability of labors and engineers

– Availability of sufficient space for power plant equipments,

space for disposing ash, space for storing coal etc.



Working Principle:



• Advantages-

Fuel is cheaper

Less space is required as compared with Hydro-electric power

plant

Cheaper in production cost and initial cost compared with

diesel power plant

Transmission Costs are reduced as these plants can be set up

near the industry.



• Disadvantages:-

The Cost of plant is increases with the increase in temperature

and pressure.

Maintenance and operating cost is high.

Long Time is required for erecting and put in action.

Large quantity of water is required.

Coal and ash handling poses a serious problem.

Pollution causes health problem to workers and habitants near

the thermal power plant



Hydro-Electric Power Plant:

In Hydro Power Plant the water is utilized to move theturbines which in turn run the electric generator’s.

The Potential energy of the water stored in the damgets converted into the Kinetic Energy of the movingwater in the penstock. And this Kinetic Energy getsconverted into the Electrical Energy with the help ofTurbine & Generator (T-G) combination.

Hydro Power Plant was invented by H.F. Rogers

Hydro Power Plant fulfills the 30% of the total energyneeds of the world.

Total hydro potential of the world = 5000 GW



First Hydro Power Plant was constructed at Darjeeling in 1898

named as “SIDRAPONG” of capacity 130 KW.

Second Hydro Power Plant was constructed at Mysore in1902 named as “ SIVARAMUDRAM ” having capacity 4.5MW.



Essential Elements of Hydro-Electric Power Plant.

PRIMARY ELEMENT’S

CATCHMENTS AREA

RESERVOIR

DAM

PRIME MOVERS

DRAFT TUBES

POWER HOUSE & EQUIPMENT

SAFETY DEVICE’S

SPILL WAY’S

SURGE TANK

TRASH RACK



Hydro-electric power station

transformer

generator

lock gate

turbine



1.Catchment Area:

The whole area behind the clam training into a stream asriver across which the dam has been built at suitable placeis called catchments area

2.Reservoir:

A reservoir is employed to store water which is furtherutilized to generate power by running the hydroelectricturbines.

3.Dam:

- A dam is a barrier which confines or raise water for storageor diversion to create a hydraulic head.

- Dam’s are generally made of concrete, Stone masory,Rockfill or Timber.



4. Turbine and Generator:

Turbine & Generator is the most important part of any

power plant

This combination is known as THE HEART OF THE

POWER PLANT.

TURBINE :- Turbine is a very light fan like structure

having many number’s of blades . It has an ability to

rotate on its axis when water passes through it.

GENERATOR :- Generator is a device in which when

there is rotation of coil between the strong Magnetic

Field then it produces an Alternating Current.



5. Penstock:

Penstock is the connecting pipe between the dam & the turbine house.

It helps to increase the kinetic energy of the water coming from the dam.

Penstock is made up of a very strong material which can sustain thehigh pressure of water.

6.Draft Tube:

- Draft Tube is an empty structure made beneath the Turbine. It serves infollowing 2 purpose’s :

It allows the turbine to be set above tail water level without loss of head,to facilitate inspection and maintenance.

It regains by diffuser action, the major portion of the kinetic energydelivered to it from the runner.

It increases the output power.

It increases the efficiency of Hydro Power Plant



7.Power House & Equipment

- Some more components are required for the proper, user friendly &

smooth functioning of the power plant. These components are as follow:

VALVE :- This the instrument which is used to control the pressure of

flow of water .

PUMPS :- This device is used to send water or any fluid from lower

potential to higher potential.

8. Spillway:

Spill Way’s is a kind of canal provided besides the dam.

Spill Way’s is used to arrange the excess of accumulation of water on

the dam because excess accumulation of water may damage the dam

structure



9. Surge Tank:

When there is a sudden close or decrease in pressure due to control

valve then there is a back flow of water. This creates a high pressure

zone in the penstock due to which it may burst . This effect is known as

WATER HAMMERING EFFECT .

To avoid this a tank is attached to the penstock which stores water in it .

This tank is called as Surge Tank.



Working Principle:

Initially the water of the river is in Catchments Area.

From catchments area the water flows to the dam.

At the dam the water gets accumulated . Thus the potential energy ofthe water increases due to the height of the dam .

When the gates of the dam are opened then the water moves with highKinetic Energy into the penstock.

Through the penstock water goes to the turbine house.

Since the penstock makes water to flow from high altitude to low altitude,Thus the Kinetic Energy of the water is again raised.

In the turbine house the pressure of the water is controlled by thecontrolling valves as per the requirements.

The controlled pressurized water is fed to the turbine.

Due to the pressure of the water the light weight turbine rotates.



Due to the high speed rotation of the turbine the

shaft connected between the turbine and the

generator rotates .

Due to the rotation of generator the ac current is

produced.

This current is supplied to the powerhouse .

From powerhouse it is supplied for the commercial

purposes.



Advantages:-

No fuel charges.

Less supervising staff is required.

Maintenance & operation charges are very low.

Running cost of the plant is low.

The plant efficiency does not changes with age.

It takes few minutes to run & synchronize the plant.

No fuel transportation is required.

No ash & flue gas problem & does not pollute the atmosphere.

These plants are used for flood control & irrigation purpose.

Long life in comparison with the Thermal & Nuclear Power Plant.



Disadvantages:

The initial cost of the power plant is very high.

Takes long time for construction of the dam.

Generally, Such plant’s are located in hilly area’s far awayfrom load center & thus they require long transmission lines& losses in them will be more.

Power generation by hydro power plant is only dependanton natural phenomenon of rain .Therefore at the time ofdrought or summer session the Hydro Power Plant will not

work.



• Installed Capacity: 22,500 MW ,

• Total cost of $26 Billion = Approx. Rs 1,30, 000 Crore

• 32 turbines (Francis Turbines) of capacity: 700 MW and

• 2 turbines of 50 MW capacity.



A groundbreaking man made structure



• The Tehri Dam is the highest dam in India, 5th highest in Asia and

10th highest in world on the Bhagirathi river near Tehri in

Uttarakhand, India. It is the primary dam of the THDC India Ltd.

The Tehri Dam withholds a reservoir for irrigation, municipal

water supply and the generation of 2,400 MW of hydroelectricity.



Solar Power Plant:

The intensity of solar radiation are weather dependent.

On cloudy days , the intensity is very low.

Average power available is only 1 kW/m2 in hottest

regions. Thus large collection area is required.

It is intermittent source of energy since it is not available

in night.



Working Principle:



Gujarat Solar Park the largest

solar park in the India. It's the

biggest solar farm in the world,

covering 2,000 hectare (4900

acres) of northern Gujarat, India,

and it has the capacity to

generate 600 MW of power.

600 MW of solar panels will save

around 8 million tonnes of carbon

dioxide from being released into

the atmosphere and save around

900,000 tonnes of coal &

Natural gas per year.



Wind Power:

The wind power can be generated where

the wind velocities are more than 8 kmph.

Such winds are available along the sea

coast and at high altitudes in hilly region.

The wind power is clean and non-

polluting

It has low maintenance cost and low

power generation cost of about Rs.

2.25/kWh.

It needs high capital cost of about

3.5crores/MW.

http://www.power-technology.com/projects/blyth/index.html#blyth6



Working Principle: Generator Brake Gear Box



• Advantages:-

– Non polluting.

– No fuel is required.

– The cost of generation is low.

Disadvantages:-

- More noisy.

- Weight of system is high.

- Does not provide constant output due to velocity fluctuations.