1、, .,. ._. . . . . -a-b!OECHNICiLLNOTES “w9 zr-NATIONALADVISORYiOMMIqYEEl?ORAERONAUTICS. ,-.“NO. 422.,THS AEROD!?Al!ICCHARACTERISTICS02 A MODELWII?GHAVING. A SPLITFLAP DEFLECTEDDOWNWARDAN9 K6VED.TOTHE R13AR J.By Fred 33.Weick and ThomasA. Harris LangleyMemorialAeronauticalLaboratory1.9. . . - . .4-.-
2、.-.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. s,which.were,hinged insplitbearings,coul”d%e lockedin aqy,angularposition.The testswere madewith theflaps deflectedat 15 inter-vals,orless wherenecessaryove,r;as,ufficieatrangeto,determinethe highe
3、stvalu . 500.:40 c 2.14 400Thesevaluesare shout 10 per centhigher than the max-imum lift coefficientsobtainedwith a conventionalflaphavinga chordlengthof 0.30 c. (Reference7.),Maximumliftwith flap- -. axis moved back to increasethe area.-With each size of flap the maximum=ift c=-ficie.ntincreasedas
4、the flap axis was-movedback to the0.90 c position. Withthe0.20 c flap it continuedto in-creaseslightlyas the axis was moved to the trailingedge,but with the largersizedflaps the valueswere slightlylower for the trai.ling-ed.geaxis locationthan for the one;qt.0.90 c.Contourlines showingconstantvalues
5、 of “CLMax ob-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-4 N,A,C,.A, Technic,alttoteNQ. ,422-.”8*tainedwiththetrailing edge o,fthe,flay witliinthe rangeof the positionstestedar”eshownin Y“igtisi1415, an”d16 for the three.differentflap sizes.-l?h
6、es.echartsshowthe highestvaluesof CL max forthe threeflaps to bea,sfollows,:HighestFlap si”zeCL max . Axijslocation Flap angle - -.-. +., -,!. 0.20 c 2.27 “ 1.00 c (580.30 c 2*45 “ :“” :.93 c 620.40 c 2.52 .90 c 54.0The highestvalue,whichreresentsan increaseof 98 percent over-thevalue of 1.27“forthe
7、-plainwing,was ob-tainedwith the 0,40 c flap.1% was closelyapproached, -.however,by the 0.30 c flapwhichwas only 3 per centlower.CenterofQessure.- At the angles of attackwithin.-,theordinaryflightrange,rotatingthe flap downwar-movesthe centerof pressureto the rear,and shiti”ngthe axisbackmoves the c
8、enterof pressurestillfartherto the rear.For the 0.40 c flap in the positiongivingthe highestval- ,ue of CL ax, the centerof pressureis abovt 17 per centof the chordbehindtheposition“forthe basicwing at thesameangle of attack.Althoughthis d.iffer”encemay seem .excessive,it is not likelyto cau;eg-rest
9、difficultyinconnectionwith the balanceof an airplanebecausethegreaterlift,coefficientwith the flap extendedresultsina substantiallygreaterdownwashangle,which increasesthedownloadon the tail. -Conmarisonwith thWhe maximum.lift c.qefficientof.th,eFoer wingwas 3.17as comparedwith 2.40 for theatisplit.f
10、lap inthe sameposition,which showsthe effectivenessOYtheslot in iuprovingthe air flow over the extensionairfoil.,Effecto-nairplaneperformance.-If an averageparasol,.monoplanewere fittedwiththe 0.40csplit flaphavingtheextendedpositionwhich gave the highestvalue of CL max. the landingspeed,accordingto
11、 the resultsof the presenttests,shouldbe reduced.to about 70 per cent of the ori-ginalvalue if the gross weightremainedunchanged. Thehigh speedwould be the sameas the originalif the instal-lationof %heflap did.notincrease,the parasitedrag ofthe airplane. .The originallandingspeedcouldbe obtainedwith
12、 thewink area reducedto about.50per cent Qf the originalval-ue, the gross weightremainingthe same”.In this case thehigh speed.would be increasedslightly%ut the take-offandclimbwould he impaired.The lower valuesof L/D with the flap ext”endedwouldmake possi%lemuch steeperglidesthan with the originalwi
13、ng,a great advantageirr,.makingshortlandingsover ob-staoles. ., , ., CONCLUSIONS “ .:.,.1. The maximumlift coefficientsobtainedwith thesplitflapswith the originalaxis locationswere verynearlythe same for the threeflap-sizestestedand weresomewhathigher than thosegivenby convefit”ionaltrailing-ed.gefl
14、aps.,. .,.2. The maximumlift.coefficientwas increasedby mov-ing the hinge axis of the flap%ack to”O.90c for tk.e0.40cflap,0.93 c for the 0.30 c flap,and.to the t:azliudefor the 0.20 c flap .3. The highestvalue of CL max, whichwas obtainedwith the 0.40 c flap,highesto%tainedwithhigher than thatwithwa
15、s only 3 p-ercent-igherthan thethe 0.30 c flap and 11 per centthe 0.20 c flapProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-,6 N1A,CA,.Technical.N.u.ts:”l?,o”422I.8k. With the 0.40 c flap in.th.best.Fn-sttioha dax-imuml.ift coeffici,ent-,. .-Langley
16、MemorialAeronauticalLaboratory,“1.c3.4.5,t+“.7.NationalAdvistiry”CommitteeforA6”ronautics, “Langleyl?i.eld,Vs., May 7, 1932. . .,. .REFERENCES ,.:. . .Bamber,MillardJ.: Wind-!l!mnnelTests on ah AirfoilEquippedwith a SplitFlap and a Slot!CiNi No, 324,N.A.C.A., 1929. ., .,.,., ,1,Noia,:etsuwo: The Hir
17、aki-BaneVariableSectionAir-,foil.:Paper beforeSocietyof Mechanical:Engineer$of Japanpu%lishedin HomeEditicn,Vol. 3-3,No, 155,l?pa71 13i-137. Abstractin Mech.Xng.,VOIi53, Nn, 6;P.448, ,. .,. ;-Th9,11ani?lGuggenheimFund for.the.Promotiofi6f“Aeron-autics, Inc.: The DanielGuggenheim,Interna:tionalSafeAi
18、rcraftCompetition,FinalReport,1930. ,Weick,I?redE., and Sanders,Robert: Wind-TunnelTestsof a Hall High-Lift,Wing.!l!.l?.No. 417,N.A.C,A, *1932. “ Weick,.Fred I!.,and I?latt,RobertC.: Wind-Tunnel“Testsof the FowlerVariable-AreaWing. T.N.No, 419,N.A.O.A”:,1932. Harris$ThomasA.: The 7 by 10 I?ootWind T
19、unnel“oftheNationalAdviscryCommitteeforAermautics. T.R.No. 412,NA,.C,A,1931.Weick,FredE.”, and Shortal,JosephA,: The EffectofllultipleYixedSlots and a !Crail.ing-WdgeFlap on theLift and Drag:of a ClarkY Airfoil. T.Ri Os 427,.N.AC.A., 1932. .b,.Provided by IHSNot for ResaleNo reproduction or networki
20、ng permitted without license from IHS-,-,-.,N.A,C,A.TechnicallToteNo. 422TABLE IAIRFOILORDIXATES(Allvalues in per centairfoilchord).- .- _ _-_ _Station.-. 0,1.252.505.007.5010.0015.0020.0030.0040.0050.0060.0070.0080.0090.009!5.00100.00CLARKY“OrdinateUpFer3.505.456.507.908.859.6010.6911.3611.7011.401
21、0.529.157.355.222.801.49.12-OrdinateLower3.501.931.47.93.63.42.15.03000000000Leadingedgeradius= 1.50Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-1 .-, .=ib2-J. Chord = 10” 0.90 chord O.vo”chord -rF-T-0“0chord-1I-+-.-k-.-+Il-=rangements “%0%Fig.1 F
22、lap-%/aI-JProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-.,.!T.O.A.TeohniualMoteXO.422 rigm.a;O , 1 10 ,- 10 20 ! ,. I/.-r. .,a$oes?lE.8 The30peroentoflaphingedat80peroento g.7 The30peroentoflaphingedat90paroent.oProvided by IHSNot for ResaleNo repr
23、oduction or networking permitted without license from IHS-,-,-.,.b.4I.A.O.A.TaohnlaalXoteIo.4%a Fiw.8)$ /:!1L /.;/; V”I *l.ia /f/j/ .“ y -.*Vjt/ ; .0.6 1-0,.4 -lo 0 10 x)q degzeee d,degreesFig.6The20peroentoflaphingedat Fig.9The40per oent o flaphingedat100per oento 60peroentoProvided by IHSNot for R
24、esaleNo reproduction or networking permitted without license from IHS-,-,-83.A.O.A.TeobnlcalEote10.428 rlga.10E=o.m?, T-l -.L.Z. L.E.t 0.400m : %: 1n2C A aod . -.-, , . - .-. . .,. - “-” +Op. Op.0 Igi0 , . I+,L. I00 ,/$60 +2.4a71a.oa71/1.6,. ,OL1.2 I,/1 , /o.8 I%/4 d-0.41-lo 0 80q d:ees* Tig.10The40
25、peroentoflaphingedat70peroento rig.11The 40 per oenta flaphlngadat60peroentoQProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Ali.A.O.A.TeehnloalIfote110.482 rigs.12& 13LL.E.ti.6. A aoA . ,g,. - - . . .- . . . .: -j0Z 40r)0 / .h s!9!- -*+6 00 :$f- 00=
26、 1+&-/# AB=,O:f= OQ+11 - 480 D - 15J 80 Vm = 5*f A“ E = 300 ) Xs = Ja.4a.o ,1.6 /3-LI1.a/0.8 / / /t%4.4 -10 0 10 ao 30 -10 0 10 20 30q degreee q degreeeFig.13 The40peroentoflaphingedat IY.g.la The40par oentoflaphingedatlCKIwr oento 80paroentc.Provided by IHSNot for ResaleNo reproduction or networkin
27、g permitted without license from IHS-,-,-. . . .=.-. -Range of positions.Position in per cent ,ord -IsFig.14 Contoursof CL for variouspoeitionsof trailingedge of 20per cent flapmezF.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. . . .Position impe
28、r centRange oppositions tested-.-k,z-20 -lo 0 10 2330Positionin per cent chordFig. 15 contoursof for vaioua positionsof trailingwige of ZO per cent flapProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. . , “ . .2!2z8Position in per cent *T chordI o.
29、.-_ _-. ()/ 4/Range of positionstested2.2-.32.z 2.5-XJ -10 0 “.1O m 30Position in per cent chordFig. 16 Contoursof & for var”10USpositionsof trailingedge of $!0per cent flap. ww.! “ .,-.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. . b.Powlorrig.17 Comparison&ovarizbleaxea, = 3.17i“of Yowlervariable-areawing with 40 per cent split flq.Wor.!Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
