NASA NACA-ARR-L5G25-1945 Wind tunnel investigation of control-surface characteristics XXIII a 0 25-airfoil-chord flap with tab having a chord twice the flap chord on an NACA 0009 .pdf

1、3 AH?”No.L%25.,.*- -.-53NATIONAL ADVISORY COMMITTEE FOR AERONAUTICSORIGINALLYISSUEDSeptember1945asAdvemoeRestrictedReportL5G25WIND-?UNNELJ3WESTIGA!TIONOF CON!PROL-SURFACECHARACTERISTICSXXIII- A O.25-AIRFOIL-CHORDl%4PWITHTABK/WINGACHORDTWICETHEI?LKPCHORDONAN NACA0009AIRJ?OILBy M. LeroySpeemanLangleyM

2、emorielAeronauticelLaboratoryLangleyField,Va.-.-,),:-.- -,:;$iiu”., .:T . r f:, j ii v M I(MI“)RIAI-.AKRON.A LJNLL%L . . . . . .WASHINGTONNACA WARTIME REPORTS are reprints of papers originally issued to provide rapid distribution ofadvance research results to an authorized group requiring them for t

3、he war effort. They were pre-viously held under a security status but are now unclassified. Some of these reports were not tech-nically edited. All have been reproduced without change in order to expedite general distribution.*,.Provided by IHSNot for ResaleNo reproduction or networking permitted wi

4、thout license from IHS-,-,-.4-,F.ACAAfi3NO. L5G25NATIONAL ADVISORY COMMITTIiASTNG ACHORD TWICE Tl?dFLAP CHORD OhTAN NA.C!A0009 AIRFOILBy M. ieroy SpearmanSUM?!M.RYljvr-ld-tmneltests have been made to deterfiinethe aerodynamic section chsracteri.stiesof an NACA 0009airfoil with a plain flap having a

5、chord 25 percent ofthe airfoil chord and a balancing tab having a chordO percent of the sirfoil chord or 200 percent of thela.chord so linked that the tab woulddeflect at a,givenrate with respect to theflap. Three M.nkageratios wers tested on the modeiThe tests indicated that the flap and tab could

6、belinked to give hinge-moment balanco with flap deflectionand with angle of attack and yet have greater lifteffectiveness than a plain fla of siw.ilarsize with aconventional balancing tab havkg a chord 20 percentof the flap chord linked to give M.nge-moment balancewith flap deflection only.INTROIXUC

7、TIONThe problem of closely balancing control.surfacesto reduce the hinge moments,forces,and consequently the stickwith a miimum I.OSSin lift due to the action ofthe balancing device 1s becoming fncrctis.inglyimportant.-“ An extensive investigation of control-surface character-istics is being conduct

8、ed at the Langley Laboratory ofthe National Advisory Committee for Aeronautics in anattempt to solve this problem. A briaf summary of the.characteristics of some of the balancing-tab s,rrangernentsinvestigated to date is presented in the followingpa?a.graphs.Provided by IHSNot for ResaleNo reproduct

9、ion or networking permitted without license from IHS-,-,-2It is suggested in referenca 1 that a control surfaceoverbalanced by a larg overhang with a tab deflecting inthe same direction as the flap might produce hih lift atsmall ckflectioris. This erranernentws testcdin theL.waley7- by 10-foot tunne

10、l on a finite-span tail (refr-ence 2) and the results indicated that satisfactorycontrol-surface characteristics could b obtained ovtironly a small flep-deflectio.n range. The flap deflectionwas limited by the air-flow separation when the overhangprotruded into the air stream.Previous tests (referen

11、ce 3) have shown that srnsll-chord.plain flaps at hi flap deflctions CPJ1produceas muc-hlift as large-chord balanced flaps at normaldeflections. The hih deflscti.onsof the snal.1-chordflaps gave excessive hinge moments for lme F,in2-S $however and a small-chord flap cornMnad wibh a ha:ancingdevice t

12、hst would not protrud ir.tothe air stream orlimit tlp deflections ther=fore appearc.dto be ),1=“delf).:aoTho subscripts outslde the parentlmses represet thefactors held constsxltclurin.gthe maasurew.ent o.ftineparamters.APPARATUS AND PROCZHXJRENode1.The 2-foot-chord by .-foot-spamodel (fi. 1) wgstes

13、ted in the Langley !+-by 6-foot verticd tunne1described in reference 4 .md was made ofIeminatedmzhogany to the NACA 0009 profile. Themodel was equ.i,pyedwith-a 0.2fjcflap and.a 0.50c or 2.00cf tab. For thLgap-o:pentests the gaps betwc?enthe airfoil and tihtaband between the tab and the flap weiqeO.

14、QC15C. The f18Pand tab were deflected in cpposite directions in a mannersimilar to that for conventional balancing tabs by memsof the linkage system shown schematically in figure 1,The model was so arranged that the position ofthe il:ppivot point could be moved upward, which in effectdeflected the t

15、ab upwind “, 10, or 15 (Measured ineach case when ed against flap deflection for three linkages infigure 2.Test Conditions and EquipmentThe tests were made at a dynamic pressure of 13 poundsper square foot, which corresponds to a velocity of71 Miles per hour under standard conditions. IheeffectiveRe

16、ynolds number for maximum lift toefficientsfor thesetests was approximately 2.57 x 10 . (Effective Reynoldsnumber = test Reynolds number x turbulence factor. Theturbulence factor for the Langley - by 6-foot verticaltunnel is 1.93.)The airfoil model when mounted in the tunnel com-pletely spanned the

17、test section, With this type ofinstallation, two-dimensional flow i.sapproximated andsection characteristics of the model can be determined.“.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-6 NAC!A AFR I!o. L5G25.momant are presented.CorrectionsAn ex

18、perimcntallydetermined tunael correction wasanplled to the lift The angle of atteck and hingemoments were corrected for the effsetof stremwiinecl.rvatureinduced by tlhetunnel walltiin accordance witha theoreical analysis similar to that presented.inre:frence5 for finite-span models.The tunnel-wall

19、corrections were applied.in thefollowtng maner:wherea(-J T measurehelift as well as thehinge moments of the balancing surface and the flap mustbe considered. It is Skiovin in reference 2 that thegreatest lift effecti.vm.essis obtained from a .O.25Cflzqpwith a 0.50c tab. Raference2 indicates also tha

20、t, with-.;-.this arrangement, the hinge-moment parameters could beride almost zero.The following generai relsti.ons can be shown to hold.-.fop sny two flaps hinged in series where the subscripts tand T are used for the forward and re.rwardflaps,respectively:dCl= Chf dcht duo 6 a. baodch bChf+ Ct 2)=

21、 dbf abf cfThe solutiondchn = O yields two rots. This result indicates thatthere are two values of ratio oftab deflection to flpdchdeflection which will give = O*dbf One root gives anegative value df ab which corresponds to the arrangem-ent tested; the other root gives a positive % 9 wb.ich-. indica

22、besthat the lift comes frcm the forward flap andthe balance from the rear fla-pas is the case with aconventional balancing tab. (For the arrangement tested,. the normal tab and flap positions are reversed. )Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IH

23、S-,-,-8 NACA As!?OoL525The resuits obtained with equations (3) and ()+)arapresented in figure 3 for various values of the tab-to-flap linkap;eratia. T-ehinge-riw.entdete.as presertedin reference 2 were not corrected for the effect 01siremline curvature resulting froM the jet boundaries.This streamli

24、ne-curvatlecorrection ws.sapplied to thedata of refenence 25 b.?-ever,fop the cor:putedcurves.influre5, The ratio was varied from c1to -0.25 inorclerto compube the aerodyn-mfiiccharacteristics presentedof hinge-moment paramctesis sand about 150 for the sealed g=psc This effect isprobably caused by a

25、ir-flow separation over the flep, ashas been generally observed on other airfoils havinghishly balanced flaps. For a linkage rtio of -0.15 withthe tab trimmed at zero, the hinse moments a:reveryclosely balanced for deflections up to about 10 or 15throughout the anf:le-of-sttckrgeaThe Vll.leof cha be

26、comes rloreneative as thelinkage ratio decreases. This effect is the result ofthe decrease in balancin moment produced on the flapby the tab and also of the decrease in the amount offl=p area ahead of the fixed pivot point. The balancingmoments decrease as the pivot point OT the flap movesforward an

27、d the effect is similar to that ofdecreasingthe size of an overhang balance.W?ilectintqthe ta.b_rortrimming hadlittle efIecton cha and ih rieasured at the angle of zero lift.As the tab is deflectad negatively, however, the hingemoments become ,oreclosely balanced at higher positiveangles of attack.

28、With this arrangement,higher lifts atlarfleangles of attack could be obtained with less hingemoment than could be obtained with the tab trirm.edatzero. Such a variation is desirable for landing when thepeent system is used as an elevator, or for trirmingthe yawing moment due to slipstremn rotation w

29、hen it isUS06 as a rudder on si.ngle-enRine airplanes iithe rudderdeflection and angle of attack careof opposite sign.Sealing the gaps (fig, 12) generally gives a rlorepositive value of chG for initial tab trim deflectlc)nsof both 0 and .,lo. The effect on chn ofsealing thegaps was not consistent, h

30、owevfir,since the incrmnent wasnegative for Gto = 00 d posiiive for o = -lo.C!ONCLW IONSTests were made of an NACA 0009 airfoil ?itha flaPha.vina chord 25 percent of the airfoil chord (D*2c).a71. .Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-and 2

31、 tab having a chord 200 percent of the flap chord.(Zoocf). The following conclusions were indicated:1, A flap with a.2.00cf balancing tab couldproduce hinge-moment bal.ncewith both angle of attack,mldflap deflection and yet havo,greatar lift offestivenessti-w.na l?of similar size equipped with a 0,2

32、0cF con-ventional balancin tab linked to give hinge-momentbalance wi.tk flap dflection only.2. Def3-ectin:the tab for trimmimg was about75 ercmt as ef.iecti.ve as an.adjustable stabilizer.4. Sealing both gaps generly increase?the-. slopeof the U ft curve Ct(y,and the l.ft eftectivmess ofthe flap CL9

33、erldgve more. positive values for the rateof chmge o hinge-moment coefiicientwith flap.def1.ecti.on Chb ,5* with the tab dofl.ectcdnegzti.vely for trim, thehinge moments were clos(lybalanced at Mg;h positivealglesof a,ttac,whj.ch is desirable for the landingCol?ditionoLangley Memori.a.lAeronautical

34、LaboratoryNational Advi.ory Comni.tteefor AeronauticsLangley Field, Va.-.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA AM NO. L5G25 .2.3.5.#6*W?FEIR.ZNCLES .Provided by IHSNot for ResaleNo reproduction or networking permitted without license f

35、rom IHS-,-,-. NACA ARNO. L5G .25-.-TAEILEICHARACTERISTICS OF A oe 25c FLAP WIT!HA 2.00cf AND A 0,20cf TA.B.-. . ii c/cf ! b5#a5fItL-/-”.-:f-c-4Ch(jj- -,. I -.JU.-15 - a71 10 ,-15 -.25 ,-15 -o a71-*L09709609709709997C99.-. - 1-O .00M i -0.0026 I. Oooj .Cmj :.OC?lJ .0054-.00i6 I -.0052 jo -.mni I-.001

36、8 i -.oc3b Ia71 0012 .0007 ia71 00L+ . ool+ I.=Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA ARR No, L5G25 Fig. la-c.g , =c=ons. NACA 0009 airfoil.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-

37、Fig. 2 NACA ARR Oo L5G25.o-2-4z 6-8*NATONALAlVISORY21MMlTlEEFORIERONAUlx) 5 /0 15 20 25 30. .Flap deflection, 6f, degFigure 2.- Characteristics of /inkoge testecl .-m the NACA 0009 airfoil wiih a 0.25 cflap and a 2.00 cf tab. .Provided by IHSNot for ResaleNo reproduction or networking permitted wi

38、thout license from IHS-,-,-NACA ARR No. L!jG,25d-.a71.008 Gapsk 0 Sealed 0.005C.004 Sealed (calculated ron dab OTreference 2 )dc o 4) p. .0 :004 Ydsf 4- A:4:8.0088.004 dc c1 ov:m :008 , hMIONALA)VISORV70/2 CWW:EEFORRONAUIos;24 20 716 :/2 708 704 - 0(?A5fFig. 3ifigure 3. -ompu-kon of the aerodynamic

39、char-aceics of the 2.00 cf /Qb on M-ACA 0009 airfojlobjained from experiment and from calculdio m.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Fig. 4a NACA ARR No. L5G251$i.21,0.8.6.4.20-,2-.4-.6-.%-/,0-1.2-w-20 -16 -/2 -8 -4 0 4 B 12 /6Angle of a

40、ttack, do, deg(a) Gaps,UJ!k?c; 40=OO;Mt/Mf= -0.10. Concluded.- Figut-e 4.- Continued.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Fi. 4b . NA(!AARR No. L5G25i.+1.2I.(?.8.6.4.20-J?-. M?= -0./5.F? 4.- C00#j0Ue6!Provided by IHSNot for ResaleNo reprod

41、uction or networking permitted without license from IHS-,-,-NACA ARR No. L5G25 Fig,.040-.04:081.2-.t.o.,.8-.-.6.-/. oIIIH3+”M-t-l/1/,. b-b-b 12-u-_lAngle Ofattack ,“tio, deg(c) Gaps, O.005c; tO=O“; b ho -5 ; Xfldgp =-o.iLl .Figure 5.- Aerodynamic section characteristics of anNAGA0009 airfoil havinga

42、0.2SCflapGUMIa 2.00ctab withvarious linkages. .Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA ARR No. L5G25 Fig. 5a Cone,. .20.16./2SO$.040-,04-.0$-,/2-.16ht.= -5; Myaf=-Qf5-figure 5.- Comhw?d. .Provided by IHSNot for ResaleNo reproduction or n

43、etworking permitted without license from IHS-,-,-* b,“ , . .a71 20“ 10“5o 0./2 a75 -5-c Q-loI %#.t I 1 R 1 t 1 1 1 1 I 1 1 1 1 tI I I Iu I I I I I tt-1 1, .-., ,-, I II I I lAll I I rRF%slF -57I I I I r%1 I1 I I II +ddt-iI I I I I I I I Irrl I I I 6tO=-5”j d06 r 4 .0 20.0 10 ,:/2 -.o -A 5-0 0-.16 h

44、5A -/0NATIOIALAVISOR:20 cowMllTEEFORPERONAJTN3 -20a-30 L-20 -/8 -/2 -8 -4 0 4 8 /2 . IL7 20Angle of Hick, OLO,deg(c) Gaps,05c; 6to= -5, Xfxf = -L?20. concluded./_re 5-Concluded.zo.Cn(aProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Fig. 6a NACA ARR

45、No. L5G25/.21,0,8.6.4g -,4%+3-/.0-1,2-/.4-M8p .1131(deg)Q20“ 105: -:A -10 1/1/ kII II IW-20”111 !(1Illlld-aoltl d / / 73.I I 1 1 b 1 1 I a 1 IIkd IIHHHH,IM!J!11till iLYkvlt-t-i+1 - 3* /. - , , , P 8 I , 1 , ! 1I20 16. -12 $ -4 0 4 B 12 /6 20Angle of attack, ocO,deg(a) Gaps, 0.N5c; Kto =- 10” j M/M=

46、0.10.Figure 6.- Aerodynamic section characterktics ofan /VACA 0009 airfoil having a 0.25c ffap and a2.00 cf tab wifh varovs linkages.-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA ARR No.a71.bou“.-./2-./6Fig. 6a Cone.-20 -/6 -12 -8 -4 0 4 8 12 /6 20Angle of attack, w ,deg(a) GaDs, QO05C d&tlb+= -0/0. Cmwuded.“. .Figur 6.- COntjntied Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-