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Gas Turbines

Øyvind HundseidMars 10, 2011

Siemens SGT5-8000H (340MW)

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Gas Turbines

Øyvind HundseidNovember 11, 2009

Siemens SGT5-8000H (340MW)

≈X 2000

Porsche Boxer

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Areas of ApplicationPropulsion Power generation

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GE - LM2500

Compressor

CombustorPower turbine

HP - Turbine

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GE LM2500 – Operational data

• Power turbine output: ~ 22 MW• Thermal efficiency: ~ 37 %• Pressure ratio: 18:1• HP turbine inlet temperature (TIT): 1270 K• HP Turbine speed: 9700 rpm• Power turbine speed: 3600 rpm

The turbine parts are exposed to high temperaturesand mechanical stress resulting in deterioration

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TurbineB

lade

spee

dCompressor

Mechanical energy

Kinetic energy

Pressure

Bla

desp

eed

Pressure

Kinetic energy

Mechanical energy

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T3

Inlet/outler pressure

Combustor pressure

• GT cycle characterized by pressure ratio and turbine inlet temperature, T3

• Increased turbine inlet temperature, T3, increases thermal efficiency and power output

Comp.

Comb.

Turb1 4

32T3

The Gas Turbine Cycle

4 2 1

2

4 2 1

3

3 2

3

3 (

shaft

fuel fuel LHV

p p

p

P h h hEff

hh

T

iciencym H h

c T cc T

T TT

ideal gas)

4 2 13p pPower output m c T c T TT (ideal gas)

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• Air cooling

• Material

• Coating

Methods to increase T3

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Operational conditions

Frequent starts/stops – thermal stress

Rapid changes in loading - high turbine inlet temperature and deterioration rate

Humid environment - salt deterioration

Stable loads – low deterioration rate

10 Snøhvit - Gas turbine system

Filter house Inlet duct,

silencer

Gas turbine Exhaustduct

Bleed duct

Ventduct

14.1 m

22.4 m

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JetCat SPM5-20

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13

1 

2 34

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6 

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Startmotor 

Innløp 

Sentrifugalkompressor

Diffusor

1.turbin

(Legg merke til at de to turbinene er frikoplet, dvs. 2 akslinger) 

2.turbin (kraftturbin) 

Eksoskanal

Aksling til generator

• Arbeidsmediet er luft som opptrer som ideell gass• Temperaturløftet som skjer på grunn av forbrenningen er

presentert som en varmeoverføring fra en ekstern kilde.

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