SECURITY INFORMATION 246

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RESEARCHMEMORANDUM

PERFORMANCE OF AN IMPULSE-TYPE SUPERSONIC COMPRESSOR

WITH STATORS

By JohnF. Klapproth,GUY NC UnmanandEdward R. Tysl

.LewisFlightPropulsionLaboratory

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WASHINGTON sJ/ April28,1952

lH NACARME52B22.

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ADVISORYCOMMITTEEFORAERONAUTICS

RESEARCHMEMOMNDUM

PERFORMANCEOFAN IM?UISE-TYTESUPERSONICCOMPRESSORWIZHHMTQRS

By JohnF. KlapprothjGuyN. Unman,andEdwardR. Tysl

SUMMARY

An @ml.se-typesupersoniccqessor rotorwithstatorswastestedinFreon-12overa rangeofequivalenttipspeedsandweightflows.Astagepressureratioof 1.83and.anefficiencyof84.7percentwereobtainedat 69.1percentofthedesignspeedof1604feetpersecondinair. Efficiencydecreasedrapidlywithincreasingtipspeedto a valueof66.8percentata pressureratioof2.6at 96.6percentdesignspeed.

DHfusionto stitorexit~chnumhrs belaw0.6wasobtainedwi.ththestatorssetata negativeangleofattackfordesignspeedoperation.Forthisstatorsettingangle,allspeedsexcept110.6percentdesigngavecontinuousoperationas theshockwasforcedfrm statoralonetoshockinbothrotorandstator.StatorexitMachnumbersbelow0.57wereobtainedforallspeeds.~essurerecoveriesabove90percentwereobtainedacrossthestatorsforstatorentranceMachnumbersup to 1.2,withrecoverydecreasingrapidlyforMachnumbersabove1.4.

Thelimitingratiooftheflowareaenterhgthestatorstothestatorminimmnsectionareaapparentlydependslargelyonthemixinglossesbetweentherotorandthestatorandonthebo~ layerat thestatorminimumsection.Onthebasisof Limiteddata,additionalrestrictionsrequiredforstartingthesu~ersonicflowthroughthesta-torsappeartobe lesscriticalthanthosecoqutedbyone-dimensionaltheoryfara diffuserhavhg a normalshockaheadoftheinletpriortostarting.

INTRODUCTION

Theoreticalconsiderationsbasedona one-dimensionalanalysisofseveraldiffmentconfigurationsforsupersoniccaqmessors(reference1)indicatedpossiblehighstagepressureratiosfortheimpulseorshock-in-statortypecompressor.Thesupersoniccompressorutilizesa highaxialinletMachnwiber(approximately0.7)anda relativelyhightipspeedtogivesupersonicvelocitiesrelativetotherotor.Therotorpassagesoftheimpulse-typecompressoraredesignedfora largeturn-ingwithsupersonicflowthroughout,avoidingstrongshocks.Theflowentersthestatorswithsupersonicvelocitieswhereitisdeceleratedthroughsonicvelocityandturnedtotheaxialdirection.

2 ~“ NACARM E52B22

TO investigatethecharacteristicsoftheimpulse-typesupersoniccompressor,a rotorwasdesigned,built,andtestedattheNACALewislaboratory.Therotorwasdesignedfara moderatepressureratioofapproximately3:1,assumingan 85percentefficiencywithanairequiv-alenttipspeedof1604feetpersecondandanaverageturningof47°htherotorpassage.Theperformancecharacteristicsof.therotorasaseparatecomponent,testedinIYeon-12(dichl.orodifluoromethane),acommercialrefrigerant,me reportedinreference2.

A setof statorswasbuiltforthedesigndischargeconditionsoftheimpulse-typesupersoniccompressorrotorofreference2,andtheperformanceinFreon-12oftheccmqmessorasa completestageispre-sentedherein.AnanalyBisoftheperformanceofthestatorsismadeforthestatorbladesettinganglewherestatorexitMachnunbersbelow0.6wereobtainedforallspeeds.

ST!AYORDESIGN

Thedesignofthestatorswasbasedontheestimatedrotorexl.tconditions.ThedesignvectordiagramfortherotorpitchsectionisshownLafigurel(a).Witha 10percentlossofthetotalpressurerelativeto therotorassumed,thecomputedexitMachnuuiberat themeanradiuswas1.79at ansingleof27°. Sincetheestimatedsugleenter~thestatorsvariedonlyfrom29°to 25°fromroottotipandtheMachnmhr variedfrom1.55to 1.79,thestatorswere designedona two-dtiensionalbasisusingconditionsatthemeanradius.

Thestator~assagesweredesignedsuchthattheflowenteredpsr-alleltothesuctionsurfaceattheleadingedge(fig.l(b)),withAleading-edgewedgesqle of10°. Thewavepatternwascontainedinsidethebladepassagewiththeflowturnedsupersonicallytotheaxialdirec-tion. TheminimumsectionareawasdeterminedfromtheentranceareaandtheI@ntrowitzcontractionratioforair(reference3)atthedesignentranceMachnuniber(1.79).Aftera shortconstant-areaminimumsection,thesubsonicportionofthebladedivergedsuchthatthepassageareaincreasedata ratecorrespondingto a 5° diffuserconehavingan equiv-alentminimumarea.Theest=ted exitMachnunber,whena 10percentboundarylayersndwakeallowmceandnormalshocklossesattheminimumsectionMachntierwereassumed,was0.48.

Thebladeheightwasconstantat 1.02inches,witha chcmdlengthof5.29inches.The25bladesata meandiameterofM inchesresultedina solidltyof2.8. Theleadingedgeofthestatorswasplacedapproxhtely2 inchesdownstreamofthetrailingedgeoftherotor.Aphotographoftherotarandstatorsbeinginstalledinthetestunitisshowninfigure2.

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I?ACARliE5Z822 3

APPARAWSANDIN6TRUIENTATION

Therotorsadstatorc~inationwasinvestigatedinFreon-12usingthevariablecmonent testrigdescribedinreference2 andshownsthematicallyb figure3. Thecqressorwasdrivenby a 3CXXlhorse-powervsriable-frequencymotortitha speedcontrolof*O.5 ~ercent.ArecirculatingsystemwasusedinwhichtheFreoninlettemperaturew%maintainedby passingthehotgasesthroughtwincoolerassemblies.

Theover-all.ratingofthecompressorwasobtainedasrecommended& reference4 usb.gtheim.strumen-tionintheentiancetankandthatat station5 (about8.75in.downstreamoftherotoror1.5in.down-streamofthestators). Theexittemperatureat station5 wasmeasuredby twocalibrated3-pointtotal-temperaturerakes.

Total-pressuremeasurementsat station5 wereobtainedby 15shieldedtotal-pressureprobes.Theannularsegmentbehinda singlestatorpassagewasdividedtitoM equalareasby fivecircumferentialandthreeradialincraentswiththetotal-pressureprobeslocatedattheareacenters.Theprobeswerespacedaroundtheannulush corre-spondingpositionsbehindthestatorpassagessuchthata msx- oftwoprobesfellbehindanyonepassage.Total-pressuremeasurementsatstation4 betweentherotorandstatorsweremadeby 3 shieldedprobeslocatedat thecenterofthreeequalannularareas,3/4-inchdownstreamoftherotor.Total-temperatureandtotal-pessureinstrumentsweresetatan averagesingleas determinedby testsad wereinsensitivetoangleovertherangeencountered.

A probeactuatorwitha cone-typecmibinationprobe(reference2)wasusedat station4 todetermimetherotordischargeconditions.Wallstaticpressuresweremeasuredontheinnerandouterhousingsattheinstrumentstationsandalongthestatorpassage.

Theweightflowwasmeasuredby staticpressuresontheinletfair-ingnozzle,whichwascalibratedagainsta knownadjustableorifice.

Ova-allbinationwere

PROCEDURE

perform&cedatainFreon-12fortherotorandstatorcom-obtainedovera rangeofbackpressuresfromopenthrottle

to stau at sevenwheelqpeedsfrm 1.10.6P=centto 55pcent ofthedesignequivalentspeed(1604ft/seetipspeedinair). Forthesedatatheinletstagnationpressurewasmaintainedbetween30and32 inchesofmercuryabsolute,andtheinlettemperaturewasmaintainedbetween100°and130°F. Frequentmeasurementsofthetest-gaspurityweremadeduringtheruns,withthepuritybeingmaintainedat 97percentorbetter.ThecomputationmethodsaresimilartothoseusedinappendixBofreference2,wheretheyareconsideredinmoredetail.

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4 NACARM E52B22

Compressorrotorspeedh Freon-12.- ThedesignspeedinFreon-12wascomputedsoas to obtaimthedesi~relativeentranceMachnuniberattherotortip(fig.4). TheresultingdesignequivalentspeedUt/@’inFreon-12isthen772feetpersecondcomparedwith1604feetpersecondforstandardupstreamconditionsinafi. (Thesyuibolsusedhereinaredefinedintheappendix.) Withtheguidevaneturningprcihmingaspanwisevariationintheabsoluteentrsmcevelocity,itwasimpossibletomatchexactlyforFreon-12therelativeinletMachnumbersatallotherradiibecauseoftheslightvariationinthevelocityofsoundarisingfromthedifferentvaluesof y forairandFreon-12.

WeigQtflow.- TheweightflowofFreon-12wascalculatedby useofthestandardnozzleequations(reference5) andstaticpressuresmeas-uredintheinletsection.Theapproximateairequivalentweightflowwascalculatedas describedb appendixB ofreference2 andisusedbpresentingthee~erimentalresults.

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the

thethe

wasforthe

Pressureratio.- Theover-allpressureratioswerecomputedusinginletstagnationconditionsmeasuredintheinletdepressiontank

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an sreaweightedaverageofthetots3-pressureprobesdownstreamofstators(station5). Onlyconditionsof subsonicvelocitiesleavingstatorswereusedb plottingtheover-all.performancemap. .-

Theaveragetotalpressurebetweentherotorsndstator(station4)obtainedby correctingtheaveragedreadingsoftheshieldedprobes

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normalshocklosses.TheaverageMachnumberwasdeterminedfromaveragedinnerandouterwallstaticpressuressmdtheobserved ._

totalpressuresusing therelation.fortheMachnuniberasa functionofthestaticpressureupstreamoftheshocktothetotalpressurebehindtheshock.

Adiabaticefficiency.- Thetotalconditionsattheentranceandexitwereusedto determinetheenthalpyrisefora constantentropyprocessandfortheactualprocess,usingthethermodynamictablesofreference6. Theratiooftheenthalpyriseunderthesetwoconditions

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wasusedastheadiabaticefficiency.Whencomparedwiththeefficiencyobtainedusingtheobservedtotal-pressureratioandtemperatureratio,andanaveragey, theefficiencyusing thethermodynamictableswasabout2 potitsluwer. Theadiabatiqefficiencymd total-pressureratioarereportedasmeasuredinRreon-12.

RESULTSANDDISCUSSION

StatorsatDesignAngle

Thestatorswereinstalledat thedesignangleandperformancewasobtainedovera rangeofspeeds.WiththedesignstatorsettinganglejdiffusionfromMachnuniberM4 of0.75to ~ of0.55wasobtained

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NACARME52B22 5

acrossthestatorsat55pffcentdesignspeed.Supersonicvelocitiesenteringthestatorswerenotobtatieduntil89.6percentdesignspeed,whereMffusionfroma l&chnuniberof 1.3.3to 0.74occurred.At thisspeed,aswelLasthelowerspeeds,thecompressorweightflowcouldbevariedwithchangesinthrottlesetting.

Fcma rotortipspeedof96.6percentdesign,a supersonicKchnumberof 1.5wasobtainedenteringthestators.At theopenthrottle(lowbackpressure)condition,supersonicvelocitieswereobtairiedthroughoutthestators.As thebackpressurewasincreaseda shockpatterncouldbe forcedintothedivergingportionofthestatorpassage,as evidencedly staticpressuresmea~uredontheinnerandoutercasings.Thisshockpatterncouldbe forcedupstreamintothestatmpassageuntiltheinczeasedbackpressurewasfeltinthestatorminimumsection.Anyf@her increaseinbackpressurecausedthecoqresscmto surge.TheminimumstatorexitMachnuniber~, obtainedwiththeentranceMachnunberof 1.5,was0.84.At a rotortipspeedof104.4percentdesign,thestatorentrmceMachnunberwas1.63,withsupersonicvelocitiesoccurrimgthrough- thestatorpassage.Forthisrotorspeed,a shockcouldnotbe forcedintothedivergingportionofthestators,withtheminimumobtainableexitMachnunhrbeing1.41inthefreestream.Anyat-t toreducethisexitMachntierby increasingthebackpressureresultedin compressorsurge.

Thus,wtththestatorsat thedesignbladesettingangle,cliffusionto theestimatedexitMachnti~ of0.48wasnotapproachedforrotorspeedsneardesign.Comparisonofthebladesettinganglewiththeobservedflowanglesleavingtherotorindicatedthatwhilethelowp?essuresurfacewaswithin2° ofthemeasuredmidstreamflowMrectionat designspeed,theangleof attackattherootandtipsectionswasapproximately+8°.

Astherotorspeedwasreducedfromberdecreased.SupersonicflowintothetheselowerMachnwbersanda shockwas

design,therotorexitMachnum-statorscouldnotbe obtainedatformedsheadofthestators.

therebyihposinga backpressureontherotor.Thisbackpressurefaceda shockto occurintherotor,whichincreasedthedensitylevelanddecreasedtheaxialvelocityattherotordischarge,resultinginlargeabsolutedischargeangles134witha correspondtiglylargeangleofattackonthestators.

Toreducetheangleofattackonthestators,thebladesettinganglewasincreasedby 7°and1.2°.Theconfigurationtiththestatorangleincreasedby 12°yieldedthebestobservedperformanceandper-mitteddiffusiontoreasonablestisonicvelocities.Theover-allper-formanceofthecompressorandan analysisofthesta.torperformanceatthe12°increaseinanglearepresented.

6 ~’* NACARM E52B22

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Performanceat IncreasedStatorAngle.

Total-pressureratioandefficiency.- Thetotal-pressureratioasmeasuredinFreon-12overa rangeofequivalentspeedsis showninfig-ure5 plottedagainsttheapproximateequivalentweightflowinair.Thepressureratiois showninfigure6 plottedagainstefficiency.Theefficiencyimreasedwithbackpressureuntilitreachedam=dm?mvalue, thendecreasedwitha furtherincreaseinbackpressureforalJ-except110.6and104.4percentdesignspeed,wherethemaximumefficiency

m

occurredatmaximumbackpressure.~ generaltheefficiencydecreased !$rapidlywithrotorspeed,forexample,from84.7percentata pressureratioof1.83forthe69.1percentdesignspeedto an efficiencyof66.8percentata pressureratioof2.6at96.6percentdesignspeed.Theincreaseinpressureratiowasveryslightingoingfrom96.6percentto 110.6percentdesignspeed.

StatorexitMachnunibers.- TheMachntiersobservedatthestatorexit ~ basedonanaveragetotalpressureandu averagestaticpres-sureat station5 areshowninfigure7 plottedagainstthestagepres-sureratio.Forthespeedsinvestigated,supersonicstatorexitveloc-itiescouldbeobta~d at openthrottlejhowever,thedataarepresentedonlyforconditionsofsubsonicexitvelocities.Statordischarge~chnunbersbelow0.57wereobtainedat alloperatingspeeds.

Rotordischargeangles.- Therotordischargeanglesmeasuredin.

themidspanposition3/4-inchdownstreamoftherotorareshownb fig-ure8 plottedagainstweightflow. TheUmitingMne ofminimumdis-chargeangleis shownforoperationwiththestatorsaswellasforthe

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rotoralone(reference2). Thestatorsettinganglemeasuredtangenttothelowpressuresurfaceatthestitorbm~ lead- e~e iSalsoindicated.

For96.6,104.4,and110.6percentdesignspeedtheminimumrotordischargeangle(whichoccursat lowback~essures)remainedfairlyconstant.Forthesespeedsthecompressoroperatedwithsupersonicflowthroughouttherotorpassages,as indicatedbythestaticpressureontheoutercasingsndthemeasuredconditionsat station4. Thedis-chargemgleswerewithin1°oftheobservedangleswithoutstators.

Forspeedslowerthah96.6percentdesign,thepresenceofthestatarsappreciablyreducedtherotordischargeanglefromthatobservedwhenoperatimgwithoutstators.As anticipatedinreference7,whentherotorspeedwasreduced,theMachnuniberenteringthestatorswasdecreasedandtheare-arestrictionofthestatorsforceda shockpatterntoformattheexitofthecompressorin orderto increasethedensity

x

levelandtherotordischargeangle.As therotorspeedwasfurtherreduced,thestatorrestrictioncausedtheshockpatterntomoveupstreamthroughtherotorpassage.At 69.1percentdesignspeed,where -

lWK!ARM E52B22 7

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themax- weightflowisslightlylessthanthatobtainedintestsoftherotoralone,theshockconfigurationoccurredjustat theentrancetotherotorpassage.(TherelativeMachnumberat therotor ‘entremceM3’ forthisspeedwasapproximately1.24.)A reductioninmaxhumweightflawfrom20.5to 18.1poundspersecondwasobservedat 55percentspeed.

Thestatorisseento operateat a negativeangleofattackforspeedsabove89.6percentdesign.Forthisanglesetting,a 10°com-pressionwaveformsatthelow~essuresurfaceofthestators.Thisco~ressionwaveforneardesignspeedsfalJsjustinsidethestatorpassage.Thusa stistantialreductioninMachntier is obtainedJustatthestatorpassageentrance,asrecamendedinreference7. However,theflowwasobservedtobe steadyfora rangeof~chnunbers (1.6to1.8)andcouldbeestablishedwithouttheuseofa variablegeometrystator.

Statorperformsmce..-Theeffectivenessofthestatorsmusttakeintoaccounttheamoun$ofdiffusionobtainedacrossthebladerowaswellas thetotal-pressurerecovery.~ orderto indicatebothofthesefactors,thestatorentranceMachnmiberisplottedagainstthestatordischargeFkchntiersforeachoftherotorspeeds(fig.9). Thetotal-pressurerecoveryacrossthestators(ratioofdownstreardtotalpressureto upstreamtotalpressure)isthenindicatedby recoverycon-tours.For55percentand69.1percentdesignspeed,therecoverywasvay goodevenfortheconditionof lowwei@t flowwheretheangleofattackenter~ thestators(measuredtangentto lowpressuresurfaceattheleadingedge)isupto 15°.

Forrotorspeedsof82.8percentdesignandhigher,We Machnmkmrenteringthestatorsis supersonic.ThestatorentranceMachnumberremainsconstantwithincreasingbackpressure(decreasing~) untiltheshockisforcedupstreamofthestators.ThisreducesthestatcrcentranceMachntierby alterlngtheshockpatternalreadyexistingbtherotorfor82.8percentand89.6percentdesignspeed,orby forcinga shocktntotherota passageforthe.higherspeeds.A reductionhthestatorentranceMachnuuibercouldbeobtainedforallspeedsexcept110.6percentdesignspeed.Thustheshockpatterncouldbecontrolledby thedownstreamthrottleto existh thestatoraloneorinboththerotorandthestatorwithnobreakintheperformance.Forcimgtheshockupstreamofthestatorsimprovedthestatorrecovery(principallybyreducingtheMachntier enteringthestators),butthedropinperform-anceoftherotoratthiscontition(reference2) causeda netdecreaseintheover-allefficiency.Ingeneral,therecoverywasabove90percentindiffusingfrom~ch numbersupto 1.2,buttherecoverydecreasedveryrapidlyforl!achnmibersabove1.4(fig.9).

Flowlimitationimposedby stators.-An indicationoftheeffectofthestatorsonthemaximumuss flowat lowerthandesignspeedmay

8 * I?ACARME52B22

be obtainedby consideringtheobservedflowcontractionratiofromupstreemofthestatorstothestatorm3nimumsection.Byplottingtherotordischargeangles(fig.8)againsttheexitMachnumber M4

(fig.10),a curveoflimitingangleagainstMachntier canbe obtained.Up to 96.6percentdesignspeed,thenubdmumsectionofthestatorsimposesa limitontherotordischargeconditionsatmaximumweightflow.At 96.6percentdesignspeedandabove,thestatorswillpassthemax-imumweightflowoftherotorfarthedesignconditionofno increaseb ‘-densitythroughtherotor,aadtherotorfixesthedischargeangle. g

Sincetheminimumsectionareaofthestatorpassageisknown,thecontractionofthestreamttieofwidth (2Yrr/N)cos134upstreamofthestatorsto theminimumsectioncanbe determined.The33mitingcurveoffigure10 is showninfigure11asa ratioofentrancetominimumareaplottedagainstthestatorentranceMachntier. Theobservedvaluesshowninfigure11areapproximatesincethecomputationsarebasedon

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anglemeasurementsmadeatthemidspanposition.A completelyaccuratesolutionwouldrequirea massweightedaverageoftheangleandMachnunberdistributionacrosstheannulus andcompletedataforthiscom-putationwerenotavailable.Forcomparisonpurposestheisentropiccontractionratioto a Machrnmberof1.0andtheKantrowitzratios

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(reference)forFreon-12arealsoshcmn.

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ForMachnumbersupto 1.0,thedifferencebetweentheisentropic .andobservedvaluesshowninfigureXlreflectsthemixinglossesbetweenstation4 andtheminimumsectionandtheboundary-lay=dis-placementthicknessintheminimumsection.Forsupersonicvelocities

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thedMferencereflectsanyshocklossesthatoccurbetweenstation4andtheminimumsection,themixinglossesjandtheminimumsectionboundarylayer,aswellaspossiblelimitationsonexearatiosneces- -

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saryforthestartingofthesupersonicflowthroughthestators.TheobservedcontractionratioIsseento divergefromtheisentropicratio

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withincreasingMachnumbers;however,forMachnwibersbetween1.0and1.6,therateofdivergenceislessrapidthantheI@trowitzcon-tractionratio.Abovea Machnumberof1.63theflowangleintothe

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stataswasdeterminedonlyremainednearlyconstant.

Thedataindicatethatextentonthemixinglossesboundary-layerthickaessat

by therotorandtheratioof &t/&~

theklmitingarearatiodependstoa largebetweentherotorandthestatorandthethestatorminimumsection.Theadditional

restrictionsinthesupersonicregionforthestartingofthesupersonicflowthroughthestatorsdonotappeartobe sosevereasthatcomputedby one-dimensionaltheoryfora diffuserhavinga norml shockaheadoftheinletpriorto starting(reference3).

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2H NACA~ E52E22 9

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SUMMARYOFRESULTS

An impulse-typesupersoniccompressor(rotorandstators)wasinves-tigatedinFreon-12fora rangeofrotorspeedsandbackpressures,andthefollowingresultswereobtained:

1.A stagepressureratioof1.83withan efficiencyof84.7per-centwasobtainedat 69.1percentdesignspeed(alesigntipspeedwas1604ft/secinairor722ft/secin~eon-12). Theefficiencydecreasedwithincreasingwheelspeedto a valueof 66.8percentat a pressureratioof2.6at 96.6percentdesignspeed.

2.Machnudbersbelow0.57wereobtainedatthestatorexitforall.speeds.TheMachnumbersenteringthestatorsincreasedwithrotorspeedfrom0.7to 1.79.Total-pressurerecoveriesabove90percentw~eobtaimedamoss thestatcmsforstatorentranceMachnunbersupto 1.2.Therecovery,however,felloffrapidlyforstatorentranceMachnumb~sabove1.4.

3.Thelimitingratiooftheflowareaenteringthestatorsto thestatorminimumsectiondependsto a largeextentonthemkinn lossesbetweentherotorandthestatorandontheboundarylayerat thestatorminhm section.Additionalrestrictionsnecessaryforstartingofthesupersonicflowthroughthestatarssreapparentlynotso criticalasthoseobtainedby one-&hnensionaltheoryfora diffuserhavinga normalshockaheadoftheinletpriorto starting.

4.Fordesignspeedoperation,diffusiontoMachnunibersbelow0.6wasobtainedwiththelowpressuresurfaceofthestatorbladealinedso astoforma compressionwaveattheleadingedgecompressingtheflowatthestatorpassageentrance.Forall.speedsexcept110.6percentdesign,continuousoperationwasobtainedastheshockwasforcedfromthestatoronlyto shockinboththe

LewisFlightPropulsionLaboratoryHationalAdvisoryCommitteefor

Cleveland,Ohio

rotorandthestator.

Aeronautics

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10 -–*

A3?PENDIX- SYMBOLS

NACARM E52B22.

.

Thefollowingsyuibokareusedinthisreport:

area,sqft~.

absolute14a6hnunber,ratioofabsolutefluidvelocityofsound

A

M

M’

N

P

r

T

u

w

P

T

8

~ad

e

. —,“

velocityto localN

relativetorotor 8relativeMachnuuiber,ratiooffluidvelocityto localvelocityof sound

nuniberofblades

absolutetotal,or

compressorradius~

totaltemperature,

velocityofrotor

stagnation,pressure,lh/sqft

ft

OR

(2mrN)atradiusr, ft/sec

andabsolutefluiddirection,deg

weightflow,lb/see

anglebetweencompressoraxis

ratioof specificheats .-.

ratioofactualinletpressureto standardsea-levelpressure,P~2116

adiabaticefficiency

ratioofactualinletstagnationtemperatureto standardsea-leveltemperature,T~518.2

Subscripts:

1 entrance

2 aheadof

ofnozzle _tankupstream

guidevsnes

—

3 rotorentiance

4 rotorexit.

5 downstreaminstrumentstation

~ -“

.

NACARM E52B22 u

t tip

z sxialcomponent

e tangentialcomponent

mco+Cu 1.

2.

3.

4.

5.

6.

7.

lm?ERENcEs

Wright,LinwoodC.,andKlapproth,JohnF.: PerformanceofSuper-sonicAxial-FlowCompressorsWsed onOne-DimensionalAnalysis.NACARME8L1O,1949.

Unman,Guy’N.,Hartmann,MelvinJ.,andTysl,Ed-d R.: Experi-mentalJhvestigationof a 16-fichQpulse-TypeSup~sonicCom-pressorRotor.NACARM E51G19,1951.

Kantrowitz,Arthur,andDonaldson,ColemanduP.: PreliminaryInves-tigationofSupersonicDiffusers.NACAACRL5D20,1945.

NACASubcommitteeonCompressors:StandardProceduresforRatingsndTestingMultistageAxial-FlowCompressors.NACA22N1138,1946.

Anon.: FlowMeasuremeritby MeansofStandardizedNozzlesandOrificePlates.Ch.4,pt.5,A.S.M.E.Powea?TestCedes,1940.

perry}JohnH.: Chdcal Engineers’Handbook.McGraw-HillBookco.,Inc.,2nded.,1941,p~.2577-2582.

Ferri, Antonio:PreliminaryAnalysisofAxial-FlowCompressorsHavingSupersonicVelocityattheEn~nce oftheStatac.NACARM L9G06,1949.

12 NACARME52B22

M4

A1.65\$4’.160

(a)DaOignveotordiagram(U= 1400ft/seo

forpitchaeotloninair).

= 1.79/

k27\

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(b)l)esignstatorpassage.

Figure1.- Compressordesign.

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NACARM E52B22

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Figure2.-16-inchImpulse-typesupersoniccompressorrotorand stators.

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NACAFM E52B22 15

M3’= 1.8A

‘L’~ = 0.683

/M3 = 0.721

/Passage-entrance

Ut . 16(34ft/secMt = 1.507 %,9

(a) Designfor air.

#$%J= 120

M3,Z =0.705

‘+1~ = 0.689

M3f = 1*8

Passage-entr&ce

q = 1.507 ‘3,8(b)CcqputedforFreon-12.

TFigure4. - Designentrancetipvectord.iagramfor16-inchimpulse-typesupersoniccompressorrotorinairandresultingchangesforFreon-12.

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Pm

I I I I I I I I I 122.1 25.8 29.5 33.2 36.9 40.6 4-4.3 46.0 51.7 55.4

Equivalentveightflow of Freon-12,W@/8, lb/see

Figure5. - Perfonwice chemcteriatics.

tI .,, ,

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r.,. -,-

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2.B

P P

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2.4P ~ 6 k

Design vequivalent

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T%@4

d-2.0— (percent)

0 U.O.6An 104.4

0 96.6 L=— -v 69.6

1.6— 4 82.8b 69.1A 55.0

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Design2.2— equivalent ~--.\

tip.9eedrUt @

—(percent)

o 110.62.0—n .104.4

0 96.6v S9.6

—4 82.8P 69.1A 55*O -— .-—— ——. .——..—— .—— ——. .—

1.8Ky

/

1,6

A — ——— __ -—,__ --- ._1.4 —-, -_.4 .5 .6 .7 .8

-.9 14

.

._

,0StatorexitMachnumber,M5

Figure7.-Effectofpressureratioonsiktorexit MackIn~er. ._

.

, > ,

.

@prOximte equivnl.entweight flowof air, lifi~,Ib/sw

m.wm 8. - IiOtardt Slw.1.nplottedag?dndWrcdmtn airaqpivnlnntWdglltflow.

20

2.0

1.8

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1.4

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.(

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Totiil-presfiln”ereooveryaoros6 I I I I I I

statora 1 ! I I I I I(peioed) 1111111

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95.\L i

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96

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r

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L .5 .6 .7 .8StatorexitMachnuniber,M5

Figure9. - St&or performance.

NAC!ARME52B22

.

Dadgnequivalenttipspeed,Ut/@

— (peroent)o 110.6

m4.4.: 96.6v S9.64 S2.8.b 69.1A 55.0

3!!F---,-%

———

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==+=+

it

1

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.

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.

.

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.

.

.

NACAFM E52B22 21

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g ~.u

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g! ___ __k –– ..__. _ F - \- “2

L~~th; —angl-— : — ‘— ‘—

Designequivalent

36 tlps eedrUt @

(percent)

o 1.10.632– 104.4

: 96.6 Iv 89.6 \4 82.8> 69.1A 55.0

28.6 I I.8 1.0 1.2 1.4 1.6 1.8

RotorexitMachnuuiber,~

Figure10.- Rotorexitconditions.

‘%

1.22

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1.18 /1I‘

////

/1

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1.IAWmtracblon.ratlcl

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4

Obserma data,;: -- --- Immtrqio / /

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.98 4 82.8 I

P 69.1~ 55.0

I

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-~ .mimnnceW& msr&r)~L4 1.5 1,6 1.7

mgure ‘U. - Ratio d Utatar13ntmnca m calclIlAt06m 0b8fDm&i flcm to gecmotrlo Et4ti EIMmm arm as fmctlcmof ‘9tatlnentmme Mmh mmbea?.

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