1、REPORT No. 661TESTS IN THE VARIABLE-DENSITY WIND TUNNEL OF THE N. A. C. A. 23012AIRFOIL WITH PLAIN AND SPLIT FLAPSBy IRA H. ABBOTTand HARRY GRUEiVBERGSUMhIARYSection characteridic for uge in WI-W dem”gnare pre -wrded for the N. A. C. A. %7019 airfm”l with plain andsplit $aps of 90 percent wing chord
2、 at a value of the efec-tice Reynolds Number of about 8,000,000. The j?apdefections corered CLrange from 60 upward to 76 down-ward for the plain jlap and from neutral to 90 dmimwardfor the split jlap. The split the maximum lift coefficient was alsodetermined at an effective Reynolds Number of about3
3、,800,000. The flap settings covered a range from 60upward to 75 downward for the plain flap and from0 to 90 dowmwud for the split flap. The range ofangle of attack for aU combinations e.tiended frombeIow zero lift to above maximum lift and, for the plain-flap combinations, extended through negative
4、maximumLiftexcept for flap deflections between 20 upward andthe neutraI position.PRECISIONThe precision of the data obtained from force testsin the N. A. C. k -rariabledensity tunnel is discussedin considerable deted in references 3 and 4. It isbelieved that the results may be applied with noumaleng
5、ineering accuracy to free-flight conditions at thestated values of the effective Reynolds Number. Itshould be noted, however, that the data presentedherein for the increments of mazimum lift due to theflap are somewhat lower than those obtained in someother wind tunneIs (references 5 and 6). The val
6、uesof masimum Iift coefficient contained in this reportmay be somewhat conservative.378Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-374 REPORT NO. 661NAIIONMJ ADVISORY COMMITTEE FOR mRONAUTICSRESULTS AND DISCUSSIONPresentation of results.The resul
7、ts are presented inof liftalong the wing span, and for urbtilence to correct toderived wing characteristics. The chamctaristics ofthe wing with flap neutral are obtained from tests of aplain airfoil.Maximum-lift coefBcients.-The increment of Inaxi-mum-lift coefficient due to the flap is plotted agai
8、nstflap deflection for both the plain and the split flaps infigure .10. This maximum-lift ipcrement has beenplotted “instead of the more usual maximum Rt co- “” -efficient because it has been shown (references 4 and 5)to be nearly independent of Reynolds Ntiber. Themaximum-lift increment for the spl
9、it flap increasesmore rapidly with flap defection and reaches an appre-ciably higher value than that for the plain flap.The maximum-lift incrments obtained from thesetests are appreciably lower than those obtfiined from2.82.42.0u%-1.8.4Angle ofafhdc, a , deg.Fmurm L-LUt forthe N. A. C. A. W112rectmd
10、m Wh.lS0ffW32t tfO 6W O= fOUl Pkhl hp.the effective Rejnolds Number. The methods of cor-rection are explained in reference 4 and the results socorrected are intended to represent the section data inthe form required for application to wingdesign prob-lems.Standard airfoil plots, of the form presente
11、d in refer-ence 7, for each flap deflection teeti are available uponrequest from the National Advisory Committee forAeronautics.The pitching-moment coefficients cma-,.,Ofor theflapped airfoils are computed about the aerodynamiccenter of the unflapped airfoiL Table I presentsimportant section charact
12、eristics and also certainHa4aoa4a58.8i%L02kgLt ;8.0:;:;:46.6-& o6.09. 1&6-:$:12. 3lL9M. 6lito-17.017.I19. oI&o27-405. 45. 6-3 i-1461s 616. 71.119. w.lw.078.095.0S6.342:W. lm.099.Ooa. lm.049.007.#7.024.026.C&7.OM:%!.086.694.m.111.0s2- .-.0f6.loa.lm.104. 1G3.036:%!.cw.0620.4 Ezz140169%E249m26s17627415
13、92s9140331lm84827Io2327101241lWWA2S3zmE382257.-do -.do- . . . . .-.do -.-do.-.-.5.-.2.-.1000.05.15.c&-.25-.25-.25.-.0-0-.-.4-.4-.2.3.6.6-.-.-”l”- -als - -. ls - -.16 -.- -.12 -.- -.-.6s - -.04 - -.01 .- -0 -.-.- -. w 12 7.Mr3 L8 4: OJ .:-: -.- - - .: :.- .- -: g :-: - .- -. 16 -.- .16 - -417ass .-:E
14、-.-do-_do. -_do-. -.do -_do.-_do . . . . ._do-.-.-do . . .-do. . . . . ._do-._.-do . . . . .do. -.Oloa.0035.0072.anl.0071.Ix170.0270-.0076-407 . OIlo417 . M185481 . Km:. .0071.007142a .0072484431 -:!?4.24 . mu424 -.-.-6510101615%E4546%75754.144.28 .-:Y.mw.-.0101.-do. . . . .-do.-.-.-do_._Jlo-8,89 .0
15、105420 -.0162- I6.80 .0132414 -do.-do -.-do . . . -.-do . . . . .Oas -.10 - -.-.- -.- -.- .-.- . 25 - -.Oxl -.-.- - -.- -.26 - -.109 - - - . 83 - -.162 - - -. Olm -.04 - -. owl -. m - -.ctzs -. m -.- -*.042 -.13 -.- -0.072 . 18 - -*.S2 . 22 - -! 16 . B - .-! m -.27 - -(22 . 2) - -8.6a . . - -4.70 .0
16、72.-.do . . . -.-do. -._-do . . . . . ._de_3pIt_do.-.-.-.do.-.-_do._-._-do -do- . . . .-do -_do -.-do- . . . . .IK72 -:iT-2.67 -:%-.-. .L 41 .01034E4 .ON441&51 -:Y_400 -418 -.404 .-.-?bSa -.L72 .-1Whentbe afrfotffeJnverted,a ndnus defiectkmofthe flapindkatee that the fhp is detlecteddownward.i O(cho
17、rdoft ofrfonwith fiPneutral- A refersto a chord defb?d ess he JokdngtireWremkks ofthemean Me.$Type of pressuredlstrfbntion. Seereference8.t TyL of scaleeffect on maximum Uft. M reference4.JType of Jfft.cumar asshown in the sketches.Afi /$ cTnrbnlence factorfs 2,64.7 These data Iraye ken ermcetedfor
18、tlp et7ect.Angfe of zerolfftobtafned from Uneerlfft eurre appro.dmatfng fmental Ifft cure.810w obtabicd from llnear lift curve approxfrnatlngexpei5mentel t curve.n% layoukfderangeofllft metWlent9emeredfnthaw te3ts. Valueofci. gimn applle3apPr0xirnete15over entke usefulraw of IIft coefEeients.-m11m-i.k tien abeut tfm aerodynamic centerof the efrfofl wftbaut the flap and fs the average velne.=ti.hu Velw of U, - usedfn eompntfng this ratii are tekerd mm teXs of ths Plrdnairfoil.209142-4&26Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
