Turbo Machinery Manual

7/24/2019 Turbo Machinery Manual

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S.S.G.B.C.O.E. & T., Bhusawal

Department of Mechanical Engineering

EXPERIMENT NO. 1

TO STUDY THE STEAM TURBINE SYSTEM

1


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DATE:-

EXPERIMENT No. 1

TITLE : TO STUDY THE STEAM TURBINE SYSTEM

In order to reduce rotor speed, varies method are employed. All these

keyed to common shaft and steam pressure or jet volume observed in stages as it

flows over rotor blade. This is known as compounding.

Following are three methods commonly employed for reducing motor

speed.

1 !elocity

" #ressure

$ #ressure and velocity

a) VELOCITY COMPOUNDING:

In velocity compounding impulse turbine e%pansion of steam take place ina no&&le or a set of no&&le from boiler pressure to condenser pressure the impulse

wheel carries "'$ row of moving blade.

The steam after e%panding through no&&le enter 1string of moving blade at

high velocity. A portion of this high velocity is observed by blading and

remaining by passed automatically ne%t ring of fi%ed blade. The curved of

velocity and pressure on a base ne%t ring of fi%ed blade.The curved of velocity and pressure on a base reciprocating of turbine are

shown in fig. IT may be noted that no. of pressure drop occur either in moving or

fi%ed blade. All pressure drops occur in no&&le. This turbine for same pressure

drop and diagram of wheel.

b) PRESSURE COMPOUNDING



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In this compounding of impulse turbine rings of moving blade fi%ed

no&&le are keyed to turbine but it is divided e(ually arranged all no&&le. )team boiler

is passed through no&&le ring where only small pressure drop occur within increase

in velocity steam how directed on 1stmoving blade ring where pressure of steamdoes not over but velocity decrease. This contribute one stage consist of a fi%ed ring.

)team from 1stno&&le ring enters second no&&le ring where its pressure is further

reduced. A little consideration will show that pressure drop per stage in no&&le ring

is not same but the no. of heat unit covered into velocity energy in each stage is

same. The pressure is repeated into remaining ring unit condenser pressure is

repeated.

C) PRESSURE VELOCITY COMPOUNDING:

The pressure velocity compounding of impulse turbine both the previous two

method are utili&ed. Total pressure drop of steam is divided into two stages and

velocity obtained two stages also compounded. A little consideration will show that

pressure velocity compound impulse turbine allows higher pressure. *ence lessstage is re(uired.

The curve for pressure and velocity of this turbine in fig. It may be noted that

diameter of turbine is increased and each stage of low pressure. A ring of no&&le is

fi%ed at commencement of each stage. A cartio turbine is an e%ample #.!.

compounding.

GOVERNERING OF STEAM TURBINE:

Through there are many method of governing of steam turbine throttle

governing is important.

a) THROTTLE GOVERING:

It is a method of controlling turbine o+p by varying (uality if steam entering

into turbine. This method is also known as servomotor method.



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The centrifugal governor is driven from main shaft of turbine by turbine belt

or gear arrangement. The control valve control direction of flow of oil enter in pipe

AA or servomotor or relay valve has a piston where motor is connected to needle

which move inside the no&&le. The central vertical bar -entrifugal governor caring

down of fly balls wheel also bring down the sleeve. This increase in area of

flow wheel increase of flow system turbine. As a result of turbine wheel comes to its

normal stage flywheel move up now sleeve as well as control valve rod will occupy.

It normal and turbine wheel run at this normal speed.

IT may be noted that when load on turbine decreases it will increases in it

speed as a result. IF this fly ball will go up and sleeve also go up. This will pushcontrol valve rod downward which result in opening mouth of .. This under

pressure is more piston of spear to works right which will occupy its normal position

of turbine will run at its normal speed. These are several factor which at the

performance of steam turbine. These entire factors which reduce o+p of turbine are

also known as internal losses.

NOZZLE GOVERNING:

The efciency o steam turbine is consierab!y reuce i

thrott!e "o#ernin" is carrie out at $o% !oas& An a!ternati#e' an

more efcient orm o "o#ernin" is by means o no((!e contro!& In

this metho o "o#ernin"' the no((!es are "rou)e to"ether * to +

or more "rou) an su))!y o steam to each "rou) is contro!!e by

re"u!atin" #a!#es& Uner u!! !oa conitions the #a!#es conitions

the #a!#es remain u!!y o)en&

,hen !oa on the turbine becomes more or !ess than the

esi"n #a!ue' the su))!y o steam to a "rou) o no((!es may be

#arie accorin"!y so as to restore the ori"ina! s)ee&

No((!es contro! can on!y be a))!ie to the -rst sta"e o a

turbine& It is suitab!e or sim)!e im)u!se an !ar"er units %hich



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ha#e an im)u!se sta"e o!!o%e by an im)u!se turbine& In )ressure

com)oune im)u!se' there %i!! be some ro) in )ressure at the

entry to secon sta"e %hen some o the -rst sta"e no((!es are cut

out&

BY-PASS GOVERNING:

The steam turbines are esi"ne to %or. at economic !oa it

is esirab!e to ha#e u!! amission o steam in the hi"h )ressure

sta"es& At the ma/imum !oa' %hich is "reater than the economic

!oa' the aitiona! steam re0uire cou! not )ass throu"h the -rst

sta"e since aitiona! no((!e are not a#ai!ab!e& By1)ass re"u!ation

a!!o%s or this in a turbine %hich is thrott!e "o#erne' by means o

secon by1)ass #a!#e in the -rst sta"e no((!e& Steam is by1)ass

throu"h the secon #a!#e to a !o%er sta"e in the turbine& ,hen by1

)ass o)erates it is uner the contro! o the turbine "o#ernor& The

seconary an tertiary su))!ies o the steam in the !o%er sta"e

increase the %or. out)ut in these sta"es' but there is !oss

efciency an a cur#in" o the ,i!!ian2s !ine&

In reaction turbines' because o the )ressure ro) re0uire inthe mo#in" b!aes' no((!es contro! "o#ernin" is not )ossib!e' an

thrott!e "o#ernin" )!us by1)ass "o#ernin"' is use&

NOZZLE LOSSES:

IT is important loss in impulse turbine which occurred when steam flow

through no&&le. These losses take places due to friction of )+F of blades. Friction

relatively velocity of system is reduced while gliding over the blades.



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MECHANICAL LOSSES:

It is the important loss in both turbine which occur due to friction between

shaft and wheel bearing also regarding the valve. This can be reduced by lubrication

pumps.

WHEEL FRICTION LOSSES:

It can important losses in both turbine which occurs when turbine wheel rotate

in steam. This loss takes places due to resistance offered by steam. oving turbine

blades wheel.

RESIDUAL VELOCITY LOSSES:

It is a loss on both turbines which occur due to -./. of system as it leaves

turbine wheel. It can be reduced by using multistage wheel.

MOISTURE LOSSES:

It is the loss in both turbines which take place due to moisture pressure in the

steam. The velocity of water partial is less that in steam.

RADIATION LOSSES:

It is the loss in both the turbine which takes place due to difference in

temperature between turbine and atmosphere.

0iscovery of the beneficial effect of lubrication must have forwarded crossed

upon most primitive control it is would have been (uickly recogni&ed.

)ignature with 0ateSubject In charge



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DATE:-


EXPERIMENT NO. 2

STUDY O3 4AS TURBINE"


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EXPERIMENT No. 2

TITLE: STUDY OF GAS TURBINE

INTRODUCTION:

The working principle of gas turbine is improving version of wind

mill. In order to achieve an efficient working of turbine movement of gas properly

controlled is defected on blade fi%ed in turbine runner. The air wind pressure is

supplied by an air compressor which runs by turbine itself.

In this turbine compressed air from atmosphere. Is passed to

combustion chamber where it is heated. This air when forced over moving bladeimparts rotational motion at runner. *ence air supplied is e%panded and finally to

atmosphere. The power developed by turbine to mainly use for driving compressor

and remaining for doing e%ternal work.

CLASSIFCATION:

1 According to path working substance

a -losed Type -ycle b pen -ycle

c )emi closed cycle

" According to process at heat combustion

a -onstant pressure gas turbine

b -onstant volume gas turbine

THEORY:

a) CLOSED CYCLE GAS TURBINE:

It consists of compressor, heating chamber gas turbine which

drives generator and compressor and cooling chamber. The air compressor

isentropically pressed into the heating chamber compressed air is heated using

e%ternal source and forced over turbine blade where it get e%panded. Then in cooling

chamber it is cooled at constant pressure with circulating water to original



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temperature and air again forced to compressor. It cools on 2oules and rayton cycle

as shown in fig.

Operation 1-2: The air is compressed isentropically from the lower pressure p1 to

the upper pressure p", the temperature rising from T1to T", 3o heatflow occurs.

Operation 2-3: *eat flow into the system increasing the volume from !"to !$. and

temperature from T" to T$ whilest the pressure remains constant at p"

*eat received 4 mcp5T$ ' T"

Operation 3-4: The air is e%panded isentropically from p" to p1 , the temperature

falling from T$ to T6 . 3o heat flow occurs.Operation 4-1: *eat is rejected from the system as the volume decreases from ! 6 to

!1 and the temperature from T6 to T1 whilst the pressure remains

constant at p1

*eat rejected 4 mcp5T67 T1

b) OPEN CYCLE GAS TURBINE:The fundamental gas turbine unit is one operating on theb open cycle

in which a rotary compressor and a turbine are mounted on a common shaft. Air is

drawn into the compressor and after compression passes to a combustion chamber.

/nergy is supplied in the combustion chamber by spraying fuel into the air stream,

and the resulting hot gases e%pand through the turbine to the atmosphere. In order to

achieve the net work output from the unit, the turbine must develop more gross work

output than is re(uired to drive the compressor and to overcome mechanical losses

in the drive. The products of combustion coming out from the turbine are e%hausted

to the atmosphere as they cannot be used any more. The working fluids 5air and fuel

must be replaced continuously as they are e%hausted into the atmosphere.

If pressure loss in the combustion chamber is neglected, this cycle may

be drawn on a T's diagram as shown

1'"8 represents' irreversible adiabatic compression



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"8'$ represents' constant pressure heat supply in the combustion chamber

$'68 represents ' irreversible adiabatic e%pansion

1'" represents ' ideal isentropic compression

$'6 represents' ideal isentropic e%pansion

GAS TURBINE WITH INTERCOOLING:

ajor part of power is developed by gas turbine is utili&ed by

compressing air in two stages within intercoolers between them and compredded or

efficiency of gas turbine. First air is compressed in lower pressure compressor as a

result pressure and temperature of air is increased. 3ow air passes over theintercoolers then compressed air is again compressed in high pressure compressor.

Then this air is passed through heating chamber and then through turbine. Finally air

cooled in cooling chamber and pass to low pressure compressor. The process consist

of

1'" constant #ressure *eating of air

"'$ isentropic e%pansion of air in turbine$'6 cooling at constant pressure in cooling chamber

6'9 compression in low pressure chamber

9': cooling of air in intercoolers at constant pressure

:'1 compression in high pressure compressor

workinput 5with intercooling

4 -p 5T8"7 T1 ; -p 5T867 T$

workinput 5without intercooling

-p 5T8atio 4 3et work output

?ross work output

*eat supplied with intercooling 4 -p 5T97 T86

*eat supplied without intercooling 4 -p 5T97 T8


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GAS TURBINE WITH REHEATING:

The output of gas turbine is improved by e%panding hot air in two

stages with reheater. The air is first compressed into first turbine. After cooling

stage chamber it is again passed to compressor. The process consist of

1'" heating of air in 1stheating chamber

"'$ isentropic e%pansion in 1st

turbine$'6 heating of air in heating chamber

6'9 isentropic e%pansion in "ndturbine

9': -onstant pressure cooling in intercooler

:'1 -ompression of air in compressor

3eglecting mechanical losses the work output of the *.#. turbine must be e%actly

e(ual to the work input re(uired for the compressor-pa 5T8"7 T1 4 -pg5T$7 T86

=ork output with reheating 4 -pg 5T97 T8:

=ork output without reheating 4 -pg 5T867 T8


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ta.en in the rom the combustion o ue!& 8oint 9 re)resents the

tem)erature o hot "ases at ischar"e rom the heat e/chan"er&

The ma/imum tem)erature to %hich the air cou! be heatein the

heat e/chan"er is iea!!y that o e/haust "ases' but !ess than this

is

obtaine in )ractice because a tem)erature "raients must e/ist

or an unassiste transer o ener"y&

USES OF GAS TURBINE:

1. For generation of electric power.

". It is used to drive air compressor in turbo projects they are used to drive air

compressor and turbine in turbo propeller engine.

$. They are used to drive supercharging fitted agitation and gasoline engine.

6. They are having e%tensive use in the field of railway engine.

9. ?as turbines are also used in machine engine. They does not re(uire waterstorage tank.

LOCATION:

In India there are few gas turbine power plants working such as in Assam

)tate. It has power capacity of @ = and gas turbine having capacity of "6 =.




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EXPERIMENT NO. 3

TO STUDY THE O8ERATION O3 3RAN:IS

TURBINE

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DATE:-

EXPERIMENT No. 3

AIM: TO STUDY THE OPERATION OF A FRANCIS TURBINE.

INTRODUCTION:

Francis Turbine, named after 2ames ichens Fransis, is a reaction

type of turbine for medium high to medium low heads and medium small to

medium large (uantities of water. The reaction turbine operates with itswheel submerged in water. The water before entering the turbine has

pressure as well as kinetic energy. The moment on the wheel is produced by

both kinetic and pressure energies. The water leaving the turbine has

still some of the pressure as well as kinetic energy.

THEORY :riginally the Francis turbine was designed as a purely

radial flow type reaction turbine but modern Francis turbine is a mi%ed

flow type in which water enters the runner radially inwards towards the

centre and discharges out a%ially. It operates under medium heads and

re(uires medium (uantity of water.

DESCRIPTION:

The present set'up consists of a runner. The water is fed to the

turbine by means of -entrifugal #ump, radially to the runner. The runner is

directly mounted on one end of a central )) shaft and other end is connected

to a brake arrangement. The circular window of the turbine casing is

provided with a transparent acry lic sheet for observation of flow on tothe runner. This runner assembly is supported. by thick cast iron pedestal.



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D. pen the Air release valve provided on the anometer, slowly to

release the air from manometer. 5This should be done very

carefully.

E. =hen there is no air in the manometer, close the air release valves.

1. 3ow turbine is in operation.

". Apply load on hanger and adjust the spring balance load by

hand wheel just to release the rest position of the hanger.

$. 3ote the manometer reading, pressure gauge reading and vacuum

gauge reading.

6. easure the ># of the turbine.

9. 3ote the applied weight and spring balance reading.

:. >epeat the same e%periment for different load.

@. >egulate the discharge by regulating the guide vanes position.

D. >epeat the e%periment for different discharge.

--/0C>/B

1. =hen the e%periment is over, first remove load on dynamometer.

". pen the by'pass valve.

$. -lose the ball valves provided on manometer.

6. )witch FF #ump with the help of starter.

9. )witch FF main power supply.

OBSERVATIO ! "A#"$#ATIO:

DATA:

g 4 E.D1 m+sec"

w = 1 kg+m$

m = 1$: kg+m$

-v 4 .ED

0 4 .D m

dB 4 ." m



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dR 4 .1" m

=$ 4 .$9kg

=4

4 .E:kg

OBSERVATIO TAB#E :-

SR.NO.

N!RPM)

Pd,

kg+m$Ps

mm of*g

"1

cm""

cm

=1

kg

="

kg

CALCULATIONS:

*41 #d ; # s

@:

=

= m of water

G4 ! % A ,

=

4 m$+ sec

A 4 H+ 6 d "

4



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4 m"

h 4 h17 h"

1

4

4

! 4 -v "gh J K m / w - 1 }

4

4 m+s

/i 4wgQH

1000

4

4 Lw

T 4 M = 1 ; = " ; = $ ; =6 N J g J >e

4

4 3 m

>e 4 dB ; "d>

2



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=

2

= m

Eo=2

N

T601000

4

4 Lw

; t 4 0iameter of rope, m

/i 4 Input power, k=

/ 4 output power, k=

g 4 Acceleration due to gravity, m+sec"

* 4 Total head, m



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h 4 0ifferential pressure of manometer, m

hi,h" 4 anometer reading at both points, cm

3 4 ># of runner shaft

#d 4 0elivery pressure, kg+cm"

#) 4 )uction pressure, mm*g

G 4 0ischarge, m$+sec

>e 4 /(uivalent >adius, m

T 4 Tor(ue+ 3 m

! 4 !elocity of water, m+s

=1 4 Applied weight, kg=" 4 0ead weight 5obtain from spring balance, kg

=$ 4 =eight of hanger, kg

=6 4 =eight of rope, kg

#= 4 0ensity of water, kg+m$# 4 0ensity of anometer fluid i.e. *g, kg+m$

P t 4 Turbine efficiency O

PRECAUTION # MAINTENANCE INSTRUCTIONS:

1. 3ever run the apparatus if power supply is less than $E volts and above 6"

volts". To prevent clogging of moving parts, >un #ump at least once in a fortnight.

$. Always use clean water.

1. 0rain the apparatus completely after e%periment is over.

". Always keep apparatus free from dust.



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TROUBLESHOOTING:

1. If pump does not lift the water, the revolution of the motor may

be reverse. -hange the electric connection to change the revolutions.

". If panel is not showing input, check the main supply.



EXPERIMENT NO. 4

TO STUDY THE HYDRAU$I: TURBINE

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DATE:-

EXPERIMENT No. 4

AI%: - TO STUDY THE HYDRAULIC TURBINE.

ITROD$"TIO &

Turbines are defined as the hydraulic machine which are able to convert

hydraulic energy into mechanical energy. This mechanical energy is used in running

an electric generator which is directly coupled to the shaft of the turbine. The electric

power which is obtained from the hydraulic energy is known as hydro'electric

power.

"#ASSI'I"ATIO O' ()DRA$#I" T$RBIES:-

It is classified according to the type of energy available at the inlet of

the turbine, direction of the flow through the valves head at the inlet of the turbine

and specific speed of the turbine.

1. According to the type of energy at inlet

a. Impulse Turbine

b. >eaction Turbine". According to the direction of flow through runner



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a. Tangential Flow Turbine

b. >adial Flow Turbine

c. A%ial Flow Turbine

d. i%ed Flow Turbine

$. According to *ead at inlet of Turbinea. *igher *ead Turbine

b. edium *ead Turbine

c.


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amount of water striking the runner is reduced. If the spear is pushed back, the

amount of water striking the runner increases.

2, Runner ith bucet :

It consist of a circular disc on the periphery of which a runner of

buckets which are evenly spaced are fi%ed. The shape of the bucket is of a doublehemispherical cup. /ach bucket is shaped in such a way that jet gets deflectd

through 1: to 1@

3, "aing :

The function of the casing is to prevent the splashing of water and to

discharge all water at the tail race.

4, Breaing 5et :-

=hen the no&&le is complete closed to push the spear in the forward

direction the amount of water striking the reduces to &ero.

To stop the runner in a short time, a small no&&le is provided which

directs the jet of water in the back of the vanes, this jet of water is called as

Qreaking 2et8

RADIA# '#O+ REA"TIO T$RBIE:

These turbines in which water flow into the radial direction. The water

may flow radially from outward to inward called as inward radial turbine as from

inward to outward direction called as outward radial turbine.

ain parts of a >adial Flow >eaction TurbineB

1. -asing

". ?uide mechanism

$. >unner



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6. 0raft Tube

1. "ASI6:-

The water from the penstock enters the casing completely, surrounding

the runner of the turbine such that the water may enter the runner at a%ial velocity

throughout the circumference of the runner. It is made of concrete plate steel.

". 6$IDE %E"(AIS%:-

It consists of a stationary wheel all around the runner of the turbine.

The stationary guides vanes are fi%ed on the guide vane are fi%ed on the guide

mechanism. The guide vanes allow the water to strike the vanes fi%ed on the runner,

without shock at inlet.

$. R$ER:-It is a circular wheel and which radial covered vanes are fi%ed. The

radial curved vanes are such shaped that the water enters and leaves the runner

without shock. They are keyed to the shaft.

4, DRA'T T$BE:-

A tube or pipe of gradually increasing area is used. For discharging

water from e%it of turbine to the tail race. This tube of increasing area is called the

Q0raft Tube8

'RA"IS T$RBIE:-

The inward flow turbine having radial discharging at outlet is known as

QFrancis Turbine8. In modern Francis, the water enters the runner of the turbine in

the radial direction of outlet and leaves in the a%ial direction at the inlet of runner.

Thus it is mi%ed flow turbine.



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A7IA# '#O+ REA"TIO T$RBIE:-

It the water flows parallel to the a%is of the rotation of the shaft, the

turbine is known as a%ial flow turbine and if the head at the inlet and the turbine is

sum of pressure energy and L./. revolving the flow of water through runner, a part

and pressure energy is converted in L./. the turbine is known as >eaction Turbine .For a%ial flow turbine the shaft is made longer which is known as hub.

1. #arallel Turbine B'

=hen the vanes are fi%ed to the hub they are not adjustable, that are

known as parallel turbine.

". Laplan Turbine B'

=hen the vanes on the hub are adjustable, the turbine is known asQLaplan Turbine8. It is suitable for larger (uality of watch at low heads. It consist of

a hub, adjustable vanes are fi%ed.

ain #arts of Laplan TurbineB'

1. )croll -asing

". Guick !anes mechanism

$. hub with or runner of the turbine

6. 0raft Tube




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DATE:-

DATE:-


EXPERIMENT NO. 5

TO STUDY =ARIOUS >ET 8RO8U$SIONDE=I:ES

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EXPERIMENT No. 5

AI%: - TO STUDY VARIOUS JET PROPULSION DEVICES

ITROD$"TIO &

The principal of 2et #ropulsion involves imparting momentum to amass of fluid in such a manner that the reaction of imparted momentum provides a

propulsive force. It may be achieved by e%panding the gas, which is at high

temperature and pressure, through a no&&le due to which a high velocity jet of hot

gases is produced 5in the atmosphere that gives a propulsive force. For jet

propulsion the open cycle gas turbine is most suitable.

The propulsion system may be classified as followsB1. Air stream jet engines 5Air 7 breathing engines

a. )teady -ombustion )ystemsR -ontinuous Air Flow

1. Turbo 7 2et

". Turbo 7#rop

$. >am'2et

b. intermittent -ombustion )ystem R intermittent Flow

1. #ulse 2et or Flying omb

". )elf -ontained >ocket /ngines 53on'air reathing /ngines

1.


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converted into pressureR this type of compression is called as ram

compression.

The air is further compressed to a pressure of $ to 6 bar in a rotary

compressor 5usually of a%ial flow type

The compressed air is then enters the combustion chamber 5-.-. where

fuel is added. The combustion of fuel takes place at sensible constant

pressure and subse(uently temperature rises rapidly.

The hot gases then enter the gas turbine where partial e%pansion takes

place. The power produced is just sufficient to drive the compressor, fuel

pump and other au%iliaries.

The e%haust gases from the gas turbine which atr at a higher pressure than

atmosphere are e%pended in a no&&le and a very high velocity jet is

produced which provides a forward motion to the air'craft by the jet

reaction

At the higher speeds the turbo'jet gives higher propulsion efficiency.

The turbo'jets are most suited to the air craft traveling above D km +hr

The overall efficiency of a turbo'jet is the product of the thermal

efficiency of the gas turbine plant and the propulsive efficiency of the jet.

ADVATA6E O' T$RBO-5ET E6IES:-

1. -onstruction much simpler". /ngine vibration absent.

$. uch higher speeds possible 5more than $ km+h acieved

6. #ower supply is uninterrupted and smooth.

9. =eight to power ratios superior.

:. >ate of climb higher.

@. >e(uirement interference much less.D. >adio interference much less.



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E. a%imum altitude ceiling as compared to turbo'prop and conventional piston

type engines.

1. Frontal area smaller.11. Fuel can be burnt over a large of mi%ture strength.

DISADVATA6E O' T$RBO-5ET E6IES:-

1.


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kinetic energy of the incoming air 5e(ual to aircraft velocity into pressure energy by

the diffuser. This type of compression is known as S ram effect .

RA%-5ET:

>am'jet is also called athodyd, am jet

engines have the capability to fly at supersonic speeds.

The ram jet engine consists of a diffuser 5used for compression,

combustion chamber, and no&&le.

The air enters the ram jet plant with supersonic speed and is sloweddown to sonic velocity in the supersonic diffuser, conse(uently the pressure

suddenly increases in the supersonic diffuser to the formation of shock wave. The

pressure of the air is further increased in the subsonic diffuser increasing the

temperature of the air above the ignition temperature.

In the combustion chamber, the fuel is injected through injectionno&&les. The fuel air mi%ture is then ignited by means of a spark plug and

combustion temperatures of the order of " k are attained. The e%pansion of gases

towards the diffuser entrance is restricted by pressure barrier at the after end of the

diffuser and as a result the hot gases are constrained to move towards the no&&le and

undergo e%pansionR the pressure energy is converted into the kinetic energy. The

high velocity gases leaving the no&&le provide forward thrust to the unit.

The best performance of ram jet engine is obtained at flight speed of

1@ km+h to " km+h.

ADVATA6E O' T$RBO-5ET E6IES:-

The ram'jet engine possesses the following advantage over other types of jet engine

1. 3o moving parts.

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$. =ide variety of fuels may be used.

S(ORT"O%I6S8 #I%ITATIOS:

1. It cannot be started of its own. It has to be accelerated to a certain flight

velocity by some launching device. A ram'jet is always e(uipped with a small

turbo'jet which starts the ram jet.". The fuel consumption is too large at low and moderate speeds.

$. For successful operation, the diffuser needs to be designed carefully so that

kinetic energy associated with high entrance velocities is efficiently converted

into pressure.

6. To obtain steady combustion. -ertain elaborate devices in form of flame

holders or pilot flame are re(uired.

*$#SE-5ET E6IE:

A pulse'jet engine is an intermittent combustion engine and it operates

on a cycle similar to a reciprocating engine, whereas the turbo'jet and ram'jet

engines are continuous in operation and are based on rayton cycle. A pulse'jet

engine like an athoyd, develops thrust by a high velocity of jet of e%haust gases

without the aid of compressor or turbine. Its development is primarily due to the

inability of the ram'jet to be self starting.

The incoming air is compressed by ram affecting the diffuser section

and the grid passages which are opened and closed by !'shaped non'return valves.

The fuel is then injected into the combustion chamber by fuel injectors

5worked from the air pressure from the compressed air bottles. The combustion is

then initiated by a spark plug 5once the engine is operating normally, the spark is



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turned off and the residual flame in the combustion chamber is used for

combustion.

As a result of combustion 5of mi%ture of air and fuel the temperature

and pressure of combustion products increases. ecause the combustion pressure is

higher than the ram pressure, the non'return valves get closed and conse(uently thehot gases flows out of the tail pipe with a high velocity and in doing so give a

forward thrust to the unit.

=ith the escape of gases to the atmosphere, the static pressure in the

chamber falls and the high pressure air in the diffuser force the valves to open andfresh air is admitted for combustion during a new cycle.

ADVATA6E:

1. )imple in construction and very ine%pensive as compared to turbo'jet engine.

=ell adapted to pilotless aircraft.

". -apable of producing static thrust and thrust in e%cess of drag at much lowspeeds.

S(ORT"O%I6S:

1. *igh intensity of noise

". )evere vibrations

$. *igh rate of fuel consumption and low thermodynamics efficiency.

6. Intermittent combustion as compared to continuous combustion in a turbo'jet

engine.

9. The operating altitude is limited by air density consideration.

:. )erious limitation to mechanical valve arrangement



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RO"9ET E6IES:

)imilar to jet propulsion, the thrust re(uired for rocket propulsion is

produced by the high velocity jet of gases passing through the no&&le. ut the main

difference is that in case of jet propulsion the o%ygen re(uired for combustion is

taken from the atmosphere and fuel is stored whereas for rocket engine, the fuel ando%idi&er both are contained in a propelling body and as such it can function in

!accum.

1. According to the type of peopellentsB

i. )olid propellent rocket.

ii.


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". >eliable smooth ignition.

$. )tability and ease of handling and storing.

6.


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EXPERIMENT NO. 6

STUDY AND TRIA$ ON ?A8$AN TURBINE:


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DATE:-

EXPERIMENT No. 6

TITLE:-

STUDY AND TRIAL ON APLAN TURBINE

DES"RI*TIO:-

Laplan turbine is an a%ial flow reaction U it is suitable for low head U

high discharge. Actually it is propeller turbine in which runner blade are made

adjustable hence it maintain high efficiency even under part load A Laplan

turbine runner usually four or si% blades

APPARATUS:-

Laplan turbine, flow measuring devices tachometer spring balance U

weight.

THEORY:-

For Laplan turbine flow measuring devices guide vanes arranged is

same way as for the Francis turbine U produced a tangential component efore

entering runner .The steam turns through out the duct since there is no outward

tor(ue acts. n fluids U its path of outlet of guide vanes to inlet runner. Theangular moment of fluid is converted U it is the same for any steam turbine.



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The velocity of blade being directly proportional to radial U tangential

component being inversely .proportional to radius .The blade angle vary with

radius conse(uently the blade vary U become flatter then that of the hub .As in

core of #elton wheel the relative velocity of flow in Laplan turbine is high U

changes slightly measuring the blades are relatively flat U are designed withvery little chamber so that cavitations is add.

CAVITATIONS IN $APLAN TURBINE :-

)ince there is direct relation between pressure U velocity. As velocity

increase pressure decrease when pressure reaches to vapour press. The water

press begin to full to tends the formation of vapour bubble .These vapour bubble

combed into the region of sufficient pressure .To cause condensation U hence the

surrounding li(uid reaches to fill the hole causing impulsion on the walls. The

entire phenomenon refers as cavitations .-avitations is harmful because it needs

to produce.

AB A change flow pattern resulting in low efficiency. B A high fre(. functions of press. -ombination instability U

component noise U vibration.

The primary nature this phenomenon of cavitations in addition to the

design

-avitations depend upon

1 !apour pressure or barometric pressure due to location of the

turbine above mean sea level

" )olution press at which height of runner outlet above tolerance level

$ /ffective dynamic suction head U absolute velocity of water at

runner e%it

PROCEDURE:-



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)upply the water to turbine at constant head for diff. gate for each.

opening measure the speed of turbine with the help of tachometer for diff. loading

U tabulated the reading

FORMULA :-

T-4 -avitation factor 4 5 *b' *s +**b4 arometric press. *ead in term of meter of water 4 5 *A'*!

*a4 Ave .press in m of water

*!4 )uction press head in m of water

* 4 =orking head of turbine

a%imum permissible speed 5 )pecific3s 4 9:" *b' *s+ *

G 4 -0 (1 (" "hwG % -d

(1"

' (""

I3#CT #=/> 5 # input 4 G*

# input 4

"H35T1 7 T" J > J E.D1

CT#CT #=/> 4

: J 1

/FFI-I/3-V 5 P 4 +#



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I +#

Cnit discharge 5Gunit 4 G + *

Cnit )peed 53unit 4 3 + *

Cnit #ower 5#unit 4 # + 5*$+6

OBSERVATIO TAB#E :

)r.

3o.

?ate

pening

ano. 0iff

Lg+-m"

5h1'h"

#ress.

?uage>eading5#

!accum

?uage>eading

5!

reakdrum

>eading

)peed

5>pmT1 )pring

alance

T1'T"

1"$69

)r.

3o.

?ate

pening

ano. 0iff

Lg+-m"

5h1'h"

#ress.

?uage

>eading5#

!accum

?uage

>eading

5!

reak drum

>eading

)peed

5>pmT1 )pring

alance

T1'T"

1"

$69



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CALCULATION:-

1 !enturimeter const. 4 .9:1

" -enter dist. etween pressure gauge and vaccum guage 4 .$9m

# 4 G*

For >eading 3o.1

G 4 -d J L J *

4

4 m$+sec

I3#CT #=/> 5 # input 4 G*

;

4 kw

"W35T1 7 T" J > J E.D1

CT#CT #=/> 4 : J 1

4 kw



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/FFI-I/3-V 5 P 4 +#

I +#

44

4 O

Cnit discharge 5Gunit 4 G + *

4 m$+sec

Cnit )peed 53unit 4 3 + *

4

Cnit #ower 5#unit 4 # + 5*$+6

)pecific )peed B ' 53s 4 3 #

*9+6

; rpm

RES$#T TAB#E:-

SR,

O

6ATE

O*EI

6

(EADI8* act < Gunit 3unit #unit 3s

12

3



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4

=

SR,

O

6ATE

O*EI6

(EAD I8* act < Gunit 3unit #unit 3s

12

3

4

=

"O"#$SIO:-

1> 0ischarge increases with increase in speed

2! /fficiency increases with the increase in unit speed upto a

certain root

That decreases

)ignature with 0ate

Subject In charge



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63/78




64/78


DATE :

EXPERIMENT NO. %

AIM@1

TO ST$D) T(E O*ERATIO O' A *E#TO T$RBIE.


EXPERIMENT NO. 7

TO STUDY THE O8ERATION ON A 8E$TON

,HEE$.

@


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INTRODUCTION@1

A turbine is a machine which converts the fluid energy into

mechanical energy which is then utili&ed to run the electric generator of a

power plant. Fluid used can be water or steam. The #elton wheel is atangential flow impulse turbine. The water strikes the bucket along the

tangent of the runner. The energy available at the inlet of the turbine is only

kinetic energy. The pressure at the inlet and outlet of the turbine is

atmosphere, The turbine is used for high head.

THEORY :-

#elton turbine is a impulse turbine. In an impulse turbine, all the

available energy of water is converted into kinetic energy or velocity

head by passing it through a contracting no&&le provided at the end of the

penstock. The water coming out of the no&&le is formed into a free jet, which

strikes on a series of buckets of the runner thus causing it to revolve. The

runner revolves freely in air. The water is contact with only a part of therunner at a time, and throughout its action on the runner.

DESCRIPTION:-

The set up consists of centrifugal pump, turbine unit, and sump tank,

arranged in such a way that the whole unit works as re'circulating water

system. The centrifugal pump supplies the water from sump tank to the

turbine. The loading of the turbine is achieved by rope brake drum

connected with weight balance. The turbine unit can be visuali&e by a large

circular transparent window kept at the front. A bearing pedestals rotor

assembly of shaft, runner and brake drum, all mounted on suitable cast iron

base plate.

UTILITIES REQUIRED:



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1. /lectricity )upplyB Three #hase, 6" ! A-, 9 *&, 9 k= with earth

connection.

". =ater supply 5Initial fill.

$. 0rain >e(uired.

6. Floor Area >e(uiredB 1.9 m % .@9 m.9. ercury 5*g for manometerB "9 gms.

:. Tachometer for ># measurement.

EXPERIMENTAL PROCEDURE:

S&a'&(* P'+,/':

1. -lose all the valves provided.$11h". Fill sump tank 6 with clean water and ensure that no foreign particles are

there.

$. Fill manometer fluid i.e. *g. in manometer by opening the valves of

manometer and one #C pipe from pressure measurement point of pipe.

6. -onnect the #C pipe back to its position and close the valves of

manometer.

9. pen the by'pass valve and ensure that there is no load on the brake drum.

:. )witch 3 the pump with the help of starter.

@. -lose the by'pass valve.

D. pen pressure measurement valves of the manometer.

E. pen the air release valve provided on the manometer, slowly to release

the air from manometer. 5This should be done very carefully

1. =hen there is no air in the manometer, close the air release valves.

11. 3ow turbine is in operation.

1". # of the turbine.

19. >epeat the e%periment at different load.



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>epeat the e%periment for different discharge by regulating the no&&le position

by the hand wheel provided for same.

Closing Procedure:

1. =hen the e%periment is over, first of all remove the load on dynamometer.

". pen the by'pass valve.

$. -lose the ball valves provided on manometer.

6. )witch FF #ump with the help of starter.

9. )witch FF main power supply.

:. 0rain the sump tank by the drain valve provided.

OBSERVATION ! "A#"$#ATIOS:

DATA:

? 4 E.D1 m +sec"

= 4 1 kg + m$

m 4 1$: kg+m$

-v 4 .ED

0 4 .9" m

0b 4 ." m

d> 4 .1" m

= $ 4 . 1 " E k g



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OBSERVATIO TAB#E:

Sr,

o,

*? g 8c2 h1?c h2?c +1? g +2? g

1

2

3

4

-A


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E i ;wgQH

1000

;

Re;d B+2d R

2

;

;

T ; + 1 + 3 & + 2 > @ g @ Re

;

;

E C ;2NT

601000

;

; t "oa. (an/.ing *.ant ",(,*>:

The main function of this plant is to feed coal in turbine of coal milk

when rail round wagons shifted at side. Then there are unloaded with the help of

wagons triples further the big lumps of coal are crush per re(uired si&e and then it

is fed into bankers into conveyors belts.

b> "oa. %i..:



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There are si&e si% coal mills for each boiler of capacity $$ tons coal

from banker is fed to the coal mills through the coal feeders which control the mills

in every minute.

c> 6enerator :

It is a device which converts mechanical power into electrical power.The generator produces electrically of 19.@9 kw in "1 plant and 1$.D L= in :".9

= plant with stand fre(uency 9 *X. The generator is center make.

/> "on/ener:

/%haust steam from the turbine at low pressure is entered into thecondenser where it is condensed into water and is supplied back to increase the

efficiency of the system. The condenser used is of surface type.

e> "oo.ing Toer:

It is used ot the coal the water which is usual in the condenser to

condensed the e%haust steam from the turbine. As the condenser always re(uired coil

water and due to limitation of natural resources. =e have to reverse the water again

and again the hot cooling water is cooled by cooling tower.

0> Boi.er:

It is the heart of the plant contains water tube furnace and duel no&&le and

ignitors. This power plant is tangentially fi%ed balance draught. There are 1 tubes

which carries water through boiler has refractory lining.

1. FurnaceB It is rectangular chamber surrounded by a

water tube and get heated and burner water flowing through tubes around

furnace and get heated and forms steam.

". )uper heaterB The steam so generated is at $9 - is

further superheated to 96 - by using e%haust flue gases.

$. >eheatedB In this comparatively cooler steam from *.#.

turbine is heated back to 96 - and fed to the


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6. lowersB #urpose of using root blower is to clean F+-

valve of superheated and economi&er surface which is left uncleaned

would effect the efficiency of the plant.

9. #reheatedB In this steam is cooler from *.#. turbine andis heated back to 96 - and fed to


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@. In a steam turbine there is no loss due to initial condensation of steam.

D. It can utili&e high vacuum very advantageously.

E. -onsiderable overload can be carried at the e%pense of

slightly reduction in overall efficiency.

)ignature with 0ate

Subject In charge

Turbo Machinery Manual

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