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Summary:-

The objective of this report is to develop the basic concepts of gas turbine and to study its parameters

that is(pressure ,temperature ,turbine work, compressor work , heat supplied etc.).This report also

includes the behavior of these parameter with respect to the efficiency.This report also provide the

applications, recent development and typical gas turbine models and its parameters. The environmental

effects on the gas turbine have also been discussed in this report. It is found that efficiency and

controlling of constant pressure gas turbine is more effective as compared to constant volume gas

turbine. It also includes the advantages and disadvantages of the gas turbines during their working and

controls

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Content list

 Abstract..!

Introduction"

#istory..............................................................................................................$

%as turbine cycle..&

'ajor components

 Applications...

*ecent developments..+

 Advantages disadvantages.....-"

alculation of %T parameters table...-$

/arameter graph...-&

omments..-0

1ibliography....-0

*eferences..-0

 Appendi2..-

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Introduction of Gas Turbine

 A turbine is any kind of spinning device that uses the action of a fluid to produce work. Typical fluids are3

air, wind, water, steam and helium. 4indmills and hydroelectric dams have used turbine action for decades to turn

the core of an electrical generator to produce power for both industrial and residential consumption. 5impler

turbines are much older, with the first known appearance dating to the time of ancient %reece.

(6rank whittle turbine model)

History of gas turbine:-

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In the history of energy conversion, however, the gas turbine is relatively new. The first practical gas turbine used togenerate electricity ran at 7euchatel, 5wit8erland in -+"+, and was developed by the 1rown1ovary ompany. The first gas turbine powered airplane flight also took place in -+"+ in %ermany, using thegas turbine developed by #ans /. von 9hain.In :ngland, the -+";s< invention and development of the aircraftgas turbine by 6rank 4hittle resulted in a similar 1ritish flight in -+$-.6igure -. 5chematic for a) an aircraft jet engine= and b) a land>based gas turbine

The name ?gas turbine? is somewhat misleading, because to many it implies a turbine engine that usesgas as its fuel. Actually a gas turbine (as shown schematically in 6ig. -) has aompressorto draw in and compress gas (most usually air)= acombustor(or burner) to add fuel to heat thecompressed air= and aturbineto e2tract power from the hot air flow. The gas turbine is aninternal combustion (I) engine employing a continuous combustion process. This differs fromthe intermittent combustion occurring in @ieseland automotive I engines

Gas Turbine Cycles:-

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%as turbine cycles relate to brayton cycles which is of two types

-. 9pen loop cycle.!. losed loop cycle.

The 1rayton cycle was first proposed by %eorge 1rayton for use in the reciprocating oil>burning enginethat he developed around -;. Today, it is used for gas turbines only where both the compression and

e2pansion processes take place in rotating machinery. %as turbines usually operate on an open cycle,

as shown in fig(a).6resh air at ambient conditions is drawn into the compressor, where its temperature

and pressure are raised. The highpressure air proceeds into the combustion chamber, where the fuel is

burned at constant pressure. The resulting high temperature gases then enter the turbine, where they

e2pand to the atmospheric pressure while producing power. The e2haust gases leaving the turbine are

thrown out (not recirculated), causing the cycle to be classified as an open cycle. The open gas>turbine

cycle described above can be modeled as a closed cycle, as shown in fig(b)., by utili8ing the air>standard assumptions. #ere the compression and e2pansion processes remain the same, but the

combustion process is replaced by a constant>pressure heat>addition process from an e2ternal source,

and the e2haust process is replaced by a constantpressure heat>rejection process to the ambient air.

The ideal cycle that the working fluid undergoes in this closed loop is the 1rayton cycle, which is made

up of four internally reversible processes3

• ->! Isentropic compression (in a compressor)

• !>" onstant>pressure heat addition

•

">$ Isentropic e2pansion (in a turbine)• $>- onstant>pressure heat reject.

Gas Turbines Cycles:-

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6ig(a)>(open loop cycle of %T) fig(b)>(close loop cycle of %T)

P-V & T-S diagram of Gas Turbine:-

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Major comonents of gas turbine:-

'ajor components of gas turbine are as follows.

-. ompressor.!. ombustor.". Turbine.

ompressor3

'ounted on the same shaft or coupled to the turbine.@elivery pressure is increased by multistage

construction of compressor. #owever the efficiency of multistage compressor is lower than single stage

compressor due to losses.

ombustor3

#igh>pressure air from the compressor then enters a combustion chamber where it is

mi2ed with fuel and ignited, increasing the temperature of the air to as much as -$;;,

or higher in some of the latest machines to appear. The gas turbine combustion chamber 

is specially designed to produce the minimum Buantity of 79 x . This 79 x is produced at

high temperature by a reaction between o2ygen and nitrogen in air, but this can be

controlled by controlling the combustion process so that all the o2ygen is used during

combustion, leaving none to react with nitrogen.

Turbine:

Turbineemploys vans or blades mounted on the shaft and enclosed in a casing. 5tages are always

preferred in gas turbine power plant because it helps to reduce the stresses in the bladesand

increases overall efficiency.It is essential to cool the blades for long life as these are continuously

subjected to high temperature gases. The common method is to pass cool air through holes in the

blades.

!lications of Gas Turbine:-

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Industrialgas turbines for o"er generation:

Industrial gas turbines for mec#anical dri$e

%as Turbine in surface vehicles

%as Turbine in Aircraft

%ecent de$eloments:-

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%as turbine technology has steadily advanced since its inception and continues to evolve.

@evelopment is active in producing both smaller gas turbines and more powerful and efficient engines.

'ain drivers are computer design (specifically 6@ and finite element analysis) and development of 

advanced materials 1ase materials with superior high temperature strength (e.g., single

crystal superalloys that e2hibit yield strength anomaly) or thermal barrier coatings that protect the

structural material underneath from ever higher temperatures. These advances allowed

higher compression ratios and turbine inlet temperatures, more efficient combustion and better cooling

of engine parts.

The simple>cycle efficiencies of early gas turbines were practically doubled by incorporating inter>

cooling, regeneration (or recuperation), and reheating. These improvements, of course, come at the

e2pense of increased initial and operation costs, and they cannot be justified unless the decrease in

fuel costs offsets the increase in other costs. The relatively low fuel prices, the general desire in the

industry to minimi8e installation costs, and the tremendous increase in the simple>cycle efficiency to

about $; percent left little desire for opting for these modifications.

9n the emissions side, the challenge in technology is increasing turbine inlet temperature while

reducing peak flame temperature to achieve lower 792 emissions to cope with the latest regulations. In

'ay !;--, 'itsubishi #eavy Industries achieved a turbine inlet temperature of -,0;; on a "!;

megawatt gas turbine, $0; '4 in gas turbine combined>cycle power generation applications in which

gross thermal efficiency e2ceeds 0;C.

fficiencies of Gas Turbines:-

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Calculation of various parameter of GT from

dierent pressure ratios

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!upplied data"

The gas turbine used for this investigation operates on a closed cycle with air in compressor.

/ of air D -.;;&EFGkg %amma (H) for air D -.$

Temperature at start of compression (T-)D ";;E

Temperature before turbine work (T") D -";;E

@ifferent /ressure ratios D &, 0, , , +,-;

#ressu

re

ratio

 Temp$2%

$&%

 Temp$4%

$&%

'(cienc)

$*%

 Tur+,or&

-/&

Comp,or&

-/&

eatsuppli

ed

-/&

et,or&

-/&

or&ratio

5 475.13

5

820.81

36.86 481.5

76

176.0

1

828.

8

305.5

6

.634

6 500.54

0

77.15

8

40.06 523.4

36

201.5

4

803.4

57

321.

0

.614

7 523.07

7

745.58

42.64 557.1

84

224.1

780.8

07

332.

7

.57

8 543.41

8

717.67

44.7 585.2

32

244.6

3

760.3

64

340.5

.581

562.01

5

63.3

1

46.62 60.0

263.3

2

741.6

74

345.7

7

.567

10 57.1

0

673.35

3

48.20 62.7

7

280.5

8

724.4

13

34.1

.554

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Grap +/, pressure ratio ! ,or&

ratioe(cienc) tur+ine ,or&

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'nvironmental eects of GT models"

 Tur+ine

model

!GT

100

!GT

200

!GT

400

!GT

500

!GT

600

!GT

7009:emmisi

on

;

<25pp

mv

;

<15pp

mv

;

<15pp

mv

;

<42pp

mv

;

<25pp

mv

;

<15pp

mv

Comments"

• 6rom calculated data we conclude that by increasing the pressure ratio we can increase the

efficiency of gas turbine.given table show that turbine work related to efficiency if turbine work is

ma2imum then we take efficiency of gas turbine is ma2imum.

• It can be concluded from the data if heat supplied is very high then efficiency of %T is

low.because energy in the form of heat is ma2imum loss.

• 5o by controlling the temperature and pressure we can control the turbine work and efficiency.

•  An enviorement effect of gas turbine is very important to study and overcome this problem.for 

this purpose to prevent the formation of carbon mono o2ide (9) and hydro carbons

(#),formation of nitrogen o2ide (792),and formation  of sulpherdi o2ide (59!)  in combusture

chamber.

• 6rom study we conclude that the efficiency and controlling of constant pressure %T is effective

as compared to constant volume %T.

=eferences/>i+liorap)"

%as turbine Available(http3GGen.wikipedia.orgGwikiG%asturbineJ*eferences )

%as turbine topic Available3 (http3GGen.wikipedia.orgGwikiG%asturbineJ#istory )

The gas turbine cycle Availablehttp3GGwww.yildi8.edu.trGKdagdasG1raytonC!;cycle.pdf ) omponents of gas turbine (http3GGwww.britannica.comG:1checkedGtopicG!!0$-Ggas>

turbine>engineJtoc$&-+)  Application of gas turbine available3

$http3GGen.wikipedia.orgGwikiG%asturbineJIndustrialgasturbinesforpowergeneration )

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 Advantages of gas turbine available3

$http3GGen.wikipedia.orgGwikiG%asturbineJAdvantagesofgasturbineengines .) @evelopment of gas turbine Available3

(http3GGen.wikipedia.orgGwikiG%asturbineJAdvancesintechnology ) Turbine models Available(:&;;;->%$";>A-;;>L->$A;;>%as Turbine1rochuere:M*)

?mae references"

1raytoncycle.svgGsourceDen3image3braytoncycle.svg

www.skybrary.aeroGbookshelfGbooksG-0!-.pdf 

www.a8om.com.

www.scientificdirect.com

%eto>photos.blogspot.com

@ppendices

!pecimen Calculations"

!upplied data"

The gas turbine used for this investigation operates on a closed cycle with air in compressor.

/ of air D -.;;&EFGkg, %amma (H) for air D -.$

Temperature at start of compression (T-)D ";;E

Temperature before turbine work (T") D -";;E

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A9= '@T !F##J?'K"

sBC#$T3T2%

sB1.005$1300500.54%B803.457-/-

A9= 'AA?C?'CL"

'Bnet/s

'B321.84/803.457B40.96*

A9= 9=- =@T?9"

=Bnet/tB321.84/523.44B.614

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