1、SECURITY INFORMATION copy26IRESEARCHMEMORANDUM.THEEFFECTSOFREYNOLDSNUMBERAT MACHNUMBERSUPTO 0.94 ONTHELOADINGONA 35 SWEPT-BACKWINGHAVINGNACA651A012STREAMWISESECTIONSBy Bruce E. Tiding andArmandoE. LopezAmes AeronauticalLaboratoryMoffettField, Calif.iNATIONAL ADVISORY COMMITTEEFOR AERONAUTICS1.WASHIN
2、GTONJune16, 1952 *.*.31?.57Y/3f _. .-.:.-xProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-IN NACARMA2B20-.NATIONALADVISORYCOMMITPEEFORAERONAUTICSbRESEARCHMEMORANDUMTEEEFFECTSOFREYNOLDSNUMBERATMA NUMWWUPTO0.94BACKONTHELOADINGONA 35 SWEPT-wmG HAvmGCA 6
3、51Ao=STREWWISESECTIONSByBruceE.TinlingandArmando* -.-, ,.=.-:.:.:+% SUMMARY,-,.-” E.Lopez,.*Aninvestigathasbeenmadeoftheeffectsofa variationofReynoldsnuniberonhefReynoldsnumberfrom-2,000,(X)0to4,500,000cahighervalueexistingforsectionsnearertherootofthewing,anda lowervalueexistingforsectionsnearerthe
4、tip. ItmustbenotedthatthiscorrelationisnotexactsincetheMachnumbersatwhichthesectiondataofreference10wereobtainedareprobablylowerthanthecomponentoftheMachnuniberperpen-diculartothequarter-chordlineofthewing.A correctiontothetwo-dimensionalsectiondataforthedecreaseofmaximumsectionnormal-forcecoefficie
5、ntwithincreasingMachnumber(referenceId.)wouldresultinthepointofcorrelationbeingmovedfsrthertowardthetipofthewing.Thereductioninthevalueof-themaximumsectionattheremainderoftheincreaseresultedfromarearwardmovementofthecentersofpressureofthewingsections.ThechangesinthespanwisedistributionofloadingwithR
6、eynoldsnumber,whicharetheprincipalcauseofthechangesinstaticlongitudinalstability,areevidentfromthedataoffigure20.A tentativeexplanationcanbeofferedforthelargeeffectsof .ReynoldsnumberonthiswingatMachnumbersgreaterthanthatfordragdivergence.ThesurfacepressuresontheuppersurfaceofthewingataMachnumberof0
7、.94anda normal-forcecoefficientofaboutzeroare presentedinfigure21. At20percentofthesemispan,thecompressionimmediatelybehindthepositionofminimumpressurewssmoreabruptat_aReynoldsntierof4,600,000thanataReynoldsrumiberof2,000,000.A similsrdifferenceisshowninreference14betweentheinteractionofa shockwavew
8、itha turbulentboundarylayer,andtheinteractionofashockwavewitha laminarboundarylayerwhichdoesnotseparatefromthesurface.Attheoutersections,60and101520253035404550“556065E80859095100Ordinateo.9131.1061.4141.9422.6143.1763.6k7k.3924.956;.;5:8975*9955a719975.8285.5445.1434.6544.0913.4672.7982.1061.413.71
9、9.025L.E.radius:0.922percentchordT.E.radius:0.029percentchordProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-.TABLEI1.-TABULA!I!ETIPRESSORJZCOEFFICIEltNFROM12-FOOTA!CAMACHNOMBOF0.25(a)R,10,030,000iM,0.25*CJ9, :, l, ,Provided by IHSNot for ResaleNo re
10、production or networking permitted without license from IHS-,-,-I.TABLE11.-CONT_(8)Concluded,Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-.TABLEII.-CO(b)R,6,coo,oco;M,o.21js. s,d.Im. 1, .,sProvided by IHSNot for ResaleNo reproduction or networking
11、 permitted without license from IHS-,-,-TAEi=II.-CONEDWED(b)ConcludedProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N- II.-CO(c)R,4,C00,000;M, 0.25%M,0.25ru4=a, O., I.=*m.I,o.mzI*Provided by IHSNot for ResaleNo reproduction or networking permitted w
12、ithout license from IHS-,-,-B.TABLEII.-cam.mum(d) Clmrmldea, oM,O.l,-JY-.-,.kf.u.1 , 0., d !-8 ,.s 3.0 Lo %9 7.9 ,%9 IL9 13.9 V.9, 0 I , r Iq, OM,0.81m0)IP,. ., 18 IProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-.,-%O.sl*- Wlmdmtkk.%dumg -9.7 al 04 0.8 1A 8.4 3.0 w 9.9 7.9 9.9 11.9 L3.B V*0 . 44q4d9j4qd-+jJj,., . . -I&JProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
