PowerEngineeringThirdClassTestOld3rdTLMModule3student动力工程三级考试试题试卷

Section4Lecture3Try:17.Flaretubesinagasturbineshouldbecheckedfor:

1.Thecombustionchamberofagasturbine:a.Corrosion

b.Distortion

a.Increasesthepressureofthecompressedairc.Properairflow

b.Burnsfuelwithexcessaird.Properignition

c.Islocatedbetweentheloadturbineandthe

compressorturbine8.Gasturbineunitsareused:

d.Isalwaysofthemultipleburnertype

1.Forelectricalgeneration

2.Agasturbinecombustionchamberrequires:2.Whereenergyisproducedforprocess

plants

a.Acoolingwaterjacketontheinnercanister3.Wherewastegasesfromtheprocessmay

b.Avacuumbreakerbeusedtodrive

c.Asafetypressurereliefdevicethegasturbine

d.Ahighvoltageignitionplugforinitial4.Wherehighthermalefficiencyisrequired

ignition

a.1,2,3

3.Theregeneratorofagasturbinecycleisa:b.1,3,4

c.2,3,4

a.Secondcombustord.1,2,3,4

b.Heatexchanger

c.Vesselusedtotransferheatfromtheexhaust9.Thedisadvantagesofaclosedcyclegasturbine

gastosystemare:

theworkingfluidbeforecompressionoccurs

d.Increasethepressureoftheworkingfluidin1.Morecoolingwaterisrequired

thesystem2.Morecomponentsareneeded

3.Higherinitialcost

4.Thegasturbinesystemis:4.Morespaceisrequired

a.Idealforlargegeneratorsystemsa.1,2,3

b.Idealtobeusedoverasteamturbineb.2,3,4

c.Idealtobeusedforunmannedandremotec.1,3,4

locationsd.1,2,3,4

d.Idealforallapplicationsofaprocessplant

10.Thedisadvantagesofagasturbineinclude:

5.GasturbinesoperatingontheBraytoncyclehavean

efficiencyofapproximately:1.Fuelcostsarehigh

2.Highlevelsofnoisepollutionareproduced

a.30-35%3.Lowthermalefficiency

b.35-40%4.Requiresmanyauxiliaries

c.40-45%

d.45-50%a.1,2,3

b.1,3,4

6.Inagasturbinethevolumeofairandexhaustgasesc.2,3,4

flowingthroughthecompressord.1,2,3,4

andturbine:

Section4Lecture3Try:2

a.Changeswithatmosphericpressure

b.Isalwaysthesame1.Thelowinstallationcostofagasturbineisdueto:

c.Changeswithambienttemperature

d.Changeswithloadconditiona.Cheapmaterialsinbladeconstruction

b.Lessauxiliaryequipmentneededb.1,2,4

c.Nofuelpumprequiredc.1,3,4

d.Smallfuelstoragerequiredd.1,2,3,4

2.Theregeneratorofagasturbinecycleisa:

7.Axialcompressorsusedongasturbineshavethe

a.Secondcombustorfollowingadvantages:

b.Heatexchanger

c.Vesselusedtotransferheatfromtheexhaust1.Small

gasto2.Moreefficient

theworkingfluidbeforecompressionoccurs3.Cheaper

d.Increasethepressureoftheworkingfluidin4.Runathighspeeds

thesystem

a.1,2,3

3.GasturbinesoperatingontheBraytoncyclehaveanb.1,2,4

efficiencyofapproximately:c.1,3,4

d.1,2,3,4

a.30-35%

b.35-40%8.Advantagesofgasturbinesare:

c.40-45%

d.45-50%1.Lowamountofcoolingwaterrequired

2.Lowerinitialcost

4.Wherefuelcontainingsodiumorvanadiumisbeing3.Quickstarttime

usedforagasturbine,waterwashingwill4.Highthermalefficiency

berequiredfollowedbytheadditionofchemicalsto

thefuel:a.1,2,3

b.1,3,4

a.Toreduceairpollutionc.2,3,4

b.Toreducecorrosionofexhaustductsd.1,2,3,4

c.Toreducethetemperatureoftheexhaust

gases9.Noisepollutionfromagasturbineunitcanbe

d.Toreducedepositsontheturbinebladesreducedby:

5.Gasturbinesmaybestartedremotelyby:1.Inletsilencers

2.Acousticinsulation

1.Telephone3.Byusingaxialaircompressors

2.Timedelayrelays4.Exhaustsilencers

3.Mechanicallink

4.Radiolinka.1,2

b.1,4

a.1,2c.2,3

b.1,3d.2,4

c.1,4

d.2,410.Thedisadvantagesofaclosedcyclegasturbine

systemare:

6.Gasturbinesareusedinindustryasprimemoversfor:

1.Morecoolingwaterisrequired

1.Portablegenerators2.Morecomponentsareneeded

2.Firepumps3.Higherinitialcost

3.Aircompressors4.Morespaceisrequired

4.Emergencyequipment

a.1,2,3

a.1,2,3b.2,3,4

c.1,3,4d.Isapplicabletothecompressor,turbine,

d.1,2,3,4combustorandstartingmotor

6.Amajoroverhaulisperformedonagasturbine:

a.Onanannualbasis

b.Whenperformancefallsoff

Section4Lecture3Try:3c.Duringperiodsoflightloads

d.Accordingtomanufacturer'sspecifications

1.Thecombustionchamberofagasturbine:

7.Gasturbinesareusedinlargepowerplantsto

a.Increasesthepressureofthecompressedairprovidealmost

b.Bumsfuelwithexcessairinstantemergencypowerfor

c.Islocatedbetweentheloadturbineandthe(twowords).

compressorturbine

d.Isalwaysofthemultipleburnertype

8.Advantagesofgasturbinesare:

2.Agasturbineattemptstocombine:

1.Lowamountofcoolingwaterrequired

a.Thesimplicityofthesteamturbineandthe2.Lowerinitialcost

internalcombustionengine3.Quickstarttime

b.Theadvantagesofthesteamturbineandthe4.Highthermalefficiency

internalcombustionengine

c.Theadvantagesofthesteamturbineandthea.1,2,3

simplicityoftheinternalb.1,3,4

combustionenginec.2,3,4

d.Thesimplicityofthesteamturbineandthed.1,2,3,4

advantagesoftheinternal

combustionengine9.Inagasturbinecycleusinganintercoolerthe

followingadvantagesareobtained:

3.Theregeneratorofagasturbinecyclewillrecover

aboutpercentoftheexhaustheat.1.Thespecificvolumeoftheairisreduced

2.Thecoolerairrecoversmoreheatfromthe

a.60regenerator

b.653.Thetemperatureofthesecondstage

c.70compressorwillbe

d.75increasedthusincreasingthermal

efficiency

4.Inagasturbinethevolumeofairandexhaustgases4.Moreoftheturbinepowercanbeavailable

flowingthroughthecompressorfortheoutputload

andturbine:

a.1,2,3

a.Changeswithatmosphericpressureb.1,2,4

b.Isalwaysthesamec.1,3,4

c.Changeswithambienttemperatured.2,3,4

d.Changeswithloadcondition

10.Inthetotalenergyarrangementagasturbine

5.Ingeneral,servicingcarriedoutonagasturbine:exhaustsitsfluegastoa/an:

a.Willonlybeapplicabletothecombustionunit1.Wasteheatboiler

b.Isdoneonasemi-annualbasis2.Regenerator

c.Isdoneonanannualbasis3.Exhaustheatboiler

4.Spaceheater

b.1,3,4

a.1,2c.2,3,4

b.1,3d.1,2,3,4

c.2,36.Thetotalenergyarrangementofagasturbinesystem

d.3,4isusedto:

1.Provideelectricity

2.Coolwaterfordrinking

3.Provideairconditioning

4.Provideheating

a.1,2,3

Section4Lecture3Try:4b.1,2,4

1.Thegasturbinecycleisalsoknownas:c.1,3,4

d.1,2,3,4

a.Thecurrentcycle

b.TheJoulecycle7.Aradialcompressorusedwithagasturbinehasthe

c.TheWhittlecyclefollowingadvantages:

d.TheBuchicycle

1.Simple

2.Thefreepistongasgeneratoronagasturbinecycle2.Cheap

willtaketheplaceof:3.Strong

4.Shortinlength

a.Theturbineandcombustor

b.Thecompressorandcombustora.1,2,3

c.Thecompressorandturbineb.1,3,4

d.Thecompressorandregeneratorc.2,3,4

d.1,2,3,4

3.GasturbinesoperatingontheBraytoncyclehavean8.Advantagesofgasturbinesare:

efficiencyofapproximately:

1.Lowamountofcoolingwaterrequired

a.30-35%2.Lowerinitialcost

b.35-40%3.Quickstarttime

c.40-45%4.Highthermalefficiency

d.45-50%

a.1,2,3

4.Flaretubesinagasturbineshouldbecheckedfor:b.1,3,4

c.2,3,4

a.Corrosiond.1,2,3,4

b.Distortion

c.Properairflow9.Foragasturbinetorunefficientlyyoumusthave:

d.Properignition

1.Cleanlubricatingoil

5.Gasturbineunitsareused:2.Cleangaspath

3.Cleanturbineblades

1.Forelectricalgeneration4.Cleanandgoodqualityfuel

2.Whereenergyisproducedforprocess

plantsa.1,2,3

3.Wherewastegasesfromtheprocessmayb.1,2,4

beusedtodrivethegasturbinec.2,3,4

4.Wherehighthermalefficiencyisrequiredd.1,2,3,4

a.1,2,3

10.Inagasturbinecycleusinganintercoolerthec.Thecompressorandturbine

followingadvantagesareobtained:d.Thecompressorandregenerator

1.Thespecificvolumeoftheairisreduced5.Portablegasturbinesareusedfor:

2.Thecoolerairrecoversmoreheatfromthe

regeneratora.Reducingatmosphericpressure

3.Thetemperatureofthesecondstageb.Totalenergyunits

compressorwillbec.Largeaircompressors

increasedthusincreasingthermald.Unmannedandremoteareas

efficiency

4.Moreoftheturbinepowercanbeavailable6.Thetermtotalenergyarrangement,asappliedtogas

fortheoutputloadturbinecycles,means:

a.1,2,3a.Alltheenergyisusedinthesystem

b.1,2,4b.Theturbineprovidesallthenecessaryforms

c.1,3,4ofenergy

d.2,3,4c.Thesystemisoftheclosedtypeandtherefore

Section4Lecture3Try:5lessenergyislost

d.Thehotgasesarepassedthroughaboilerto

1.Agasturbineattemptstocombine:producesteam

a.Thesimplicityofthesteamturbineandthe7.Whenagasturbineisrunningandaconditioncalled

internalcombustionenginesurgingoccursthismeans:

b.Theadvantagesofthesteamturbineandthe

internalcombustionenginea.Thespeedoftheturbineisfluctuating

c.Theadvantagesofthesteamturbineandtheb.Theturbineisrunningtoofast

simplicityoftheinternalc.Airgetschokedinthehighpressureendofthe

combustionenginecompressor

d.Thesimplicityofthesteamturbineandthed.Thefuelsupplyisfluctuating

advantagesoftheinternal

combustionengine8.Amajoroverhaulisperformedonagasturbine:

2.Thecombustionchamberofagasturbine:a.Onanannualbasis

b.Whenperformancefallsoff

a.Increasesthepressureofthecompressedairc.Duringperiodsoflightloads

b.Burnsfuelwithexcessaird.Accordingtomanufacturer'sspecifications

c.Islocatedbetweentheloadturbineandthe

compressorturbine9.Noisepollutionfromagasturbineunitcanbe

d.Isalwaysofthemultipleburnertypereducedby:

3.Theregeneratorofagasturbinecyclewillrecover1.Inletsilencers

aboutpercentoftheexhaustheat.2.Acousticinsulation

3.Byusingaxialaircompressors

60

4.Exhaustsilencers

a.b65

c7012

75a.14

d.

b.c23

24

4.Thefreepistongasgeneratoronagasturbinecycled.

willtaketheplaceof:

10.Advantagesofgasturbinesare:

a.Theturbineandcombustor

b.Thecompressorandcombustor1.Lowamountofcoolingwaterrequired

2.Lowerinitialcostd.Unmannedandremoteareas

3.Quickstarttime

4.Highthermalefficiency5.Thegasturbinesystemis:

a.1,2,3a.Idealforlargegeneratorsystems

b.1,3,4b.Idealtobeusedoverasteamturbine

c.2,3,4c.Idealtobeusedforunmannedandremote

d.1,2,3,4locations

d.Idealforallapplicationsofaprocessplant

6.Whenagasturbineisrunningandaconditioncalled

surgingoccursthismeans:

a.Thespeedoftheturbineisfluctuating

b.Theturbineisrunningtoofast

c.Airgetschokedinthehighpressureendofthe

compressor

d.Thefuelsupplyisfluctuating

7.Thebladesofanaxialcompressoronagasturbine

Section4Lecture3Try:6aremadefrom:

1.Thecompressoronagasturbine:1.Ferritesteel

2.Stainlesssteel

a.Canbedrivenbytheloadturbine3.Aluminumalloy

b.Isalwaysoftheaxialtype4.Titaniumalloy

c.Isalwaysamulti-stagecompressor

d.Canbeofthereciprocatingtypea.1,2

b.1,3

2.Theregeneratorofagasturbinecycleisa:c.2,3

d.2,4

a.Secondcombustor

b.Heatexchanger8.Inordertohavesafeandefficientoperationofagas

c.Vesselusedtotransferheatfromtheexhaustturbinetheoperatorrequires

gastoaknowledgeof:

theworkingfluidbeforecompressionoccurs

d.Increasethepressureoftheworkingfluidin1.Thelubricatingoilsystem

thesystem2.Thefueloilsystem

3.Howtocontroltheairinlettemperature

3.Thepurposeofaregeneratorinagasturbineis:4.Thefirefightingsystems

a.Tocleantheexhaustgasesa.1,2,3

b.Toimprovetheefficiencyoftheturbineb.1,2,4

c.Todecreasethetemperatureinthecombustionc.1,3,4

chamberd.2,3,4

d.Toraisetheairtemperaturebefore

compression9.Noisepollutionfromagasturbineunitcanbe

reducedby:

4.Portablegasturbinesareusedfor:

1.Inletsilencers

a.Reducingatmosphericpressure2.Acousticinsulation

b.Totalenergyunits3.Byusingaxialaircompressors

c.Largeaircompressors4.Exhaustsilencers

d.Toraisetheairtemperaturebefore

a.1,2compression

b.1,4

c.2,34.GasturbinesoperatingontheBraytoncyclehavean

d.2,4efficiencyofapproximately:

10.Thedisadvantagesofagasturbineinclude:a.30-35%

b.35-40%

1.Fuelcostsarehighc.40-45%

2.Highlevelsofnoisepollutionareproducedd.45-50%

3.Lowthermalefficiency

4.Requiresmanyauxiliaries5.Gasturbinesarefarsuperiortoothertypesof

enginesintheir:

a.1,2,3

b.1,3,4a.Fuelconsumption

c.2,3,4b.Efficiency

d.1,2,3,4c.Powerpermassratio

d.Lubricatingoilconsumption

6.Gasturbinesareusedinlargepowerplantsto

providealmost

instantemergencypowerfor

______________(twowords).

Section4Lecture3Try:77.Gasturbinesareusedinindustryasprimemoversfor:

1.Agasturbineattemptstocombine:1.Portablegenerators

2.Firepumps

a.Thesimplicityofthesteamturbineandthe3.Aircompressors

internalcombustionengine4.Emergencyequipment

b.Theadvantagesofthesteamturbineandthe

internalcombustionenginea.1,2,3

c.Theadvantagesofthesteamturbineandtheb.1,2,4

simplicityoftheinternalc.1,3,4

combustionengined.1,2,3,4

d.Thesimplicityofthesteamturbineandthe

advantagesoftheinternal8.Theadvantagesofadualshaftgasturbine

combustionenginearrangementare:

2.Agasturbineaircompressorwithanintercooler:1.Greaterflexibility

2.Itischeaper

a.Hastheintercoolerlocatedafterthe3.Smallerstartingmotormaybeused

compressor4.Highpressuresandtemperaturesmaybe

b.Increasesthevolumeofairbeingsuppliedobtained

c.Allowsmoreoutputattheturbine

d.Usedonlywithaxialtypecompressorsa.1,2

b.1,3

3.Thepurposeofaregeneratorinagasturbineis:c.2,3

d.2,4

a.Tocleantheexhaustgases

b.Toimprovetheefficiencyoftheturbine9.Noisepollutionfromagasturbineunitcanbe

c.Todecreasethetemperatureinthecombustionreducedby:

chamber

1.Inletsilencers

2.Acousticinsulationa.Idealforlargegeneratorsystems

3.Byusingaxialaircompressorsb.Idealtobeusedoverasteamturbine

4.Exhaustsilencersc.Idealtobeusedforunmannedandremote

locations

a.1,2d.Idealforallapplicationsofaprocessplant

b.1,4

c.2,35.Whenagasturbineisrunningandaconditioncalled

d.2,4surgingoccursthismeans:

10.Thelubricatingoilsystemofagasturbinemustbea.Thespeedoftheturbineisfluctuating

checkedfor:b.Theturbineisrunningtoofast

c.Airgetschokedinthehighpressureendofthe

1.Metalparticlescompressor

2.Watercontaminationd.Thefuelsupplyisfluctuating

3.Dirtcontamination

4.Leaks6.Inagasturbinethevolumeofairandexhaustgases

flowingthroughthecompressor

a.1,2,4andtur