REG NACA-TR-554-1937 Wind-tunnel investigation of ordinary and split flaps on airfoils of different profile.pdf

1、m-TuNNELREPORT No. 554INVESTIGATION OF ORDINARY AND SPLIT FLAPS ON AIRFOILS OFDIFFERENT PROFILEBy CARLJ. WENZINGDRSUMMARYThe Clurk Y, the N. A. C. A. .%012?,and the N. A. C.A. 2/?02?1airfoils equipped withfu.?l-epan ordinaqp8and with fd!+?pan t actualhinge moment8uaried approximdely a the 8quare of

2、thechord. In addition, tlw hinge-momeni toe- of the8 Jhp8 were PWhkid the 8ame as th08e of fd?-epanordifip8 of corresponding widihi?.INTRODUCIIONMany experimental investigations have been madeof various types of flap for increasing, in particular,the maximum lift of airplanes as an aid to improvedpe

3、rformance. Among the devices already investigatedin considerable detaiI by the N. A. C. A. are simple splitflaps, split flaps of the Zap type, Fowler flaps, andexternal-airfoil flaps. Some uncorrelated data are alsoavailable from various sources on sIotted flaps and on130602-87-16ordinary flaps. Bec

4、ause of the simplicity of ordinaryflaps and the lack of correlated data on them as a Iifbincreasing device, it appeared desirable to make a morecomplete invedigation of this type of flap.Three basic airfoil sections were used in the presenttests to obtain an estimate of the ellect of airfoil section

5、and thickmxw In addition to the Clark Y, theN. A. C. A. 23012 airfoil was selected as being repre-sentative of the best airfoils at present mailable foruse on conventional airplanes, and the N. A. C. A.23021 airfoil was selected as a representative thicksection. Three widths of ordinary flap ivere t

6、ested onthe Clark Y airfoil, and one width on each of the othertwo airfoils. For purposes of comparison one simplesplit flap was also tested on the N. A. C. A. 23012 and23021 airfoils, and data are included from previoustests of the Clark Y airfoil vvith a split flap. Theaerodynamic characteristics

7、of the airfoils with all thediilerent flaps were measured and, in addition, hingemoments were obtained for the ordinary flaps on theClark Y airfoiLMODELS AND TESTSModels.-Mahogany models of the Clark Y, theN. A. C. A. 23012, and the N. A. C. A. 23021 airfoilsections were tested. The span of each mod

8、el was60 inches and the chord 10 inches. The Clark Y air-foil with the 3 widths of ordinary flap tested (10,20, and 30 percent of the wing chord) is shown infigure 1. These flaps are arranged to lock rigidlyto the airfoil or to rotate hely about their respec-tive hinge axes. The other two airfoils a

9、re shownwith ordinary flaps in iigqre 2 and with split flapsin figure 3.The ordinates of the airfoil sections are includedwith the charts of their aerodynamic characteristics in .rea 4, 5, and 6. The size of flap that gave thehighest value of the maximum lift coefficient for theClark Y airfoil toget

10、har with reasonable hinge moments(20-percent-chord flap) was used with the N. A. C. A.23012 and the N. A. C. A. 23021 airfoils.Tests,The tests “were made in the N. A. C. A.7- by 10-foot wind tunnel which, together with associ-223Provided by IHSNot for ResaleNo reproduction or networking permitted wi

11、thout license from IHS-,-,-. A =_224 REPORT NO. 554 NATIONAL ADVISORY COMMIITEE FOR AERONACSated apparatus and standard test procedure, is described in reference 1. The dynamic pressure wumaintained constant at 16.37 pounds per square footwhich corresponds to amair speed of 80 miles per howunder sta

12、ndard sea-level conditions. The averagReynolds Number for the tests was 609,000, based 01the air speed and on the lo-inch airfoil chord. Lift1IGapaoo.z c-J.2”yJr,removable secfion *s,gap sealed .:. 10- , JFmumLl!ullq ordinary ab 00fllt60S40006 L-4 /, Dote:Feh 1935 Velff/see):JlZ3-_. ,/ I %ss. tZd of

13、mJ:1 Teak2676,2681, a(degrees)- - FmmE 4.The Clark Y alrfol.Jflol I I I Ill “-WI-I IT/7 I I I I I I 48.11 ! 44-P Te “ - 27=04X “ - 2740- 40AVII - “ 2813- 71 1 I 1 1 I 36 u.44 .09e“ :2.0 .4008$ 32 o1.4 .28. .05 20-2I I I I I II I I II ml1.2.24 ;.0420406080100!+=H+-l /.0 S.20; ?.(-I.3U-I-I I .4 . I J

14、1 J I 1 I 1 , I , , 0.16./2.08.04w ?r5/6;60 1111 J1111/lllN .8Sho I Ikll -$I I I n IN I VI I I I l agm 6k6“ .AC.A230.=1.IUAOU” Iucouz-u-4 / ; Dafe:June1935 V- .” . - 1 Ib4Wo I I I I I I I I%.I I I I- I I IqMO= ILLWIIW mtfo and plwg-momt fident for the Okk y akfooWfth on frdlsm OrdlrmrrfbP. P esP ./0

15、86* =90” m -_v140-2.4-,4- ILa “k%? i I I II , I6=/ *-.4 -:76 _* o 8 16 24 32 40d,degreesFowrm 13.L1fdIW, and mnti of p for the Oferk Y airfotl wfth 0.3wfrdI*pan ordbry ffep. l%p gep embi.effects as they did on the Clark Y and on the N. A.C. A. 23012 airfoils.Comparison of lift effeots of 20-peroent-

16、chordordinary and split flaps on Clark Y, N. A. C. A. 29012,20 P / L (. - -. L.f66: .f2 t!/4W ;/iifPIII III 1 1 YIJt I I I4L. 7O“aown5“ a71 -.-:10” = - Q15” - -. a7530 - A45” “ -+60” a71 -x75” * _ Pgo= “ -“CLIaum 14.-Lfft4reg ratio and pltehing-monwt meffkfmt for the Clerk Y afrfoflwith 0.3W-n mdhmr

17、g tip. Flap gap -cd.10 2.8/.Ch6 1.gD4.2.%00 20 60 80 100cfi, degreesmum 15.Effect of Sap dedmtlon on maxlmnm Ilfh and on lift-drag retlo anddrag at rneximmn ML The 02 on thmaximum lift coefficient with flaps deflected; on thincrement in maximum lift coefficient due to the twm. . / A /.8 g /,. /, “ 7

18、.4c=o-.4-. on the ratio of maxi-mum Jift to minimum drag; and on the ratio of lift todrg at m .Somewhat lher maximum lift coefficients andgreater increments in maximum lift were given by the20 (f-/ x16 / + if2 1 )/ /kI8 / I /4! #-4LO5? 6,- O“cfown o-4 3 - . 15 N -Q/* -30 . A_ =45” * -+, /=60 m - xa7

19、1 =75” . .-8 D0 i?c.; / - “. -.2 % . - - +. _ u= “.h -234 0 .4 .8 1.2 1.6 2.0CLXnmE 17.Lfft-dragIWO and pltobing-moment oxzlhdent for the Olark Y cdrfollWfth oak fnu-qmnsplitllnp.IQUREl CL1.6 /c=12,2.8,4c=o-.8.=16 -8 08 16 24 32d ,degreesOUREZ1.-Lif.J-.8-16 -8 0 8 16 24 32d, degreesCVJEEZZ.-LW drns,

20、 end centi of P1fSOi%ferthe N. LC. A.2X112efrfoJ.lwfthOa)c fnuq SW tiP-Some testsin the full-scale tunnel and in the variable-density tunnel (reference 7) indicate that the maximnm24f 20 /I /6f284rI l-l+- J4- -+ I1 v 1 ! I I I I4“- - !? a -n %MWEE!2S.-LIft-dregretio end pftchhg-moment codfchnt for t

21、he N. A. C. A.zXmfdrfoifWfthO.mfnlkpan .t Jlap., degreeshmJBE 2L-Effwt of tip detlectbn on mexlnmm lfft, end on M-drag ratio ondding at mdmnm lffL Theo.mcfuUordinw endmlItfleronthe N.A. 0. A.mu 40 I I 1 1/X_Z 46. CD.,. volne3 for fhp nmtmf., , ,II I I 11113.02,52.0,J#mC the actual hinge moments vari

22、ed approximatdyas the square of the flap chord. Both of these fidiRgsaccord with theory.5. The hinge-moment coefficients of the full-spanordinary flaps were practically the same as those ofsplit flaps of similarsize.LANGLEY MEMORIAL AERONAUTICAL LABORATORY,NATIONAL ADVISORY COMMIB FOR AERONAUTICS,LA

23、NGLEY FIELD, VA., Ocfolwr 25, 1936.REFERENCES1. Harris, Thomae A.: The 7 by 10 Foot Wind Tunnel of theNational Advisory Committee for Aeronautics. T. R. No.412, N. A. C. A., 1931.2. Wenzfnger, Carl J.: Wind-Tunnel Meaeurementa of Air Loadson Split Flaps. T. N. NO. 498, N. A. C. A., 1934.3. Theodomn,

24、 Theodore.: Interference on an Airfoilof FinitaSpan in an Open Rectangular Wind TunmJ. T. R. IQo.461, N. A. C. A., 1933.4. Glauert, H.: Wind Tunnel Interference on Wings, Bodies.and Aii%Cl?3W0. R. & M. No. 1566,Britieh A. R. C., 1933,5. Grumhwitz, Eugen, and f%brenk, OSkar: A Simple Methodfor Increa

25、ein g the Lift of Airplane Wings by Means ofFlaps. T. M. No. 714, N. A. C. A., 1933.6. Weiok, Fred E., and Harrie, Thornaa A.: The AerodynamfoCharacterktke of a Model Wing Having a Split Flap Dc-fleet.ed Downward and Moved to the Rear. T. N. No. 422,N. A. C. A., 1932. 0T. Jacobs, Eastman N., and Clay, William C.: Charaobmlstkwof the N. A. C. A. 23012 Airfoil from Tests in the Full-Scale and Variable-Dendy Tunnels. T. R. No. 530,N. A. C. A., 1935.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-