NASA NACA-TN-1248-1947 Wind-tunnel investigation of control-surface characteristics of plain and balanced flaps with several trailing-edge angles on a NACA 0009 tapered semispan wi.pdf

1、NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS i TECHNICAL NOTE CHARACTERISTICS OF PLAIN AND BALANCED FLAPS WITH SEVEML TRAILING-EDGE ANGLES ON AN a NACA 0009 TAPERED SEMISPAN WING By H. Page Hoggard, Jr. and Elizabeth G. McKinney Langley Memorial Aeronautical Labor at0 r y Langley Field, Va. Washingto

2、n April, 1947 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NATIOXAL ADVISORY GO?JdITTLE FOF AERONAUTICS CHARACTERISTICS OF PLAIN AWD BATiA5JCED FLAPS F3y 8. Page Eoggard, Jr, and Elkzabet!? G. McKinney Force tests have been made in the Langley 4-

3、by 6-foot vertical tunnel to deterln9ne the aerodynamic characterIstfes of an NACA 0009 tajere4 sem.isan. wing equipped. with a plain and a balance(3 flap havlrq-; three different incladed ang,Les at the trail-ing eggs. A comparfson was ma.3e between Lift and hinge-moment paravneter values as c.a:cu

4、lated by existing rnel2aods from two-dimensional data and tile pnra-mter valtAes .neasured from the test ckta obtained. :%E c2mptirison showed that the differences between tine neasured values of tne lift and hinge-moment parameters sn.5 the values calculated from two-diaensional dlata b37 lifting-s

5、urface theory were, in general, no greater than the giffercnces between the measured vzlues for wings of the sam aspect ratio but with different chord distributions. The effects of overhang, gap, and trailin:-edge angle on the lSft a_rid hinge-moment parsTeters were siqitar to the effects previously

6、 found in, tests of two-dimensbnd. models . Interference between bevel and overktmg was fndic coe f f 1 c imt (h/qcf2) where section lift wing mean aerodgnasic chord I7.t.A.C. 1 root-mea2-squai% chord of flap back of bfnge 1Tne sect-ion enorid of flap twPce sps.n of SePnlspm model twice span of ilp

7、air velocitz mass ,Censity of a;.r lateral distance mezsured perpendicular to root chord and Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-li- A b a a0 6 P( k E WACA TN No, la8 aspect ratio (b2/S) section chord of overhang angle of attack of chord

8、?ine angle of attack for infinite as?ect ratio flap deflection relative to airfoil; positive when trailing edge is d.efl.ected downnard trailfng-edge angle - inclu.l?ed between upper and lower surfaces sf airfoil contour at trailing edge (measured on model) constant for determfnation of jet-bou-ndar

9、y correctkm for flap hinge moment Jones 1 edge-velocity correctton factor (reference 31 Lift and hinge-moment parameters : CLa = Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA TN Nh* 5 The subscript outside the aarentheses injicates the factor

10、hsM coristmt In icterKilnfng the parsmeter, All tests were made in the Langleb 4- by 6-fbt verttcal tunnel, tkhich is eescr-ibed in reference 6, Rie taperso setrtiepan whb used ifi the tests ha9 an NACA 0009 profile (tsble 1) and was built of laminated mahogany to the plan fora shown in figure 3, Th

11、e wing had a tip af revolution, The flap chord was 30 pewen-$; of the airfoil chore- at each spanwise station, The aspect ratio of the wigg an.3 its reflection was 5, and the taper ratio was 0.5. Y ThrEfe flaos of the same plan form but with different included mieJ.es at the trailing edge wq?r,e use

12、d, The plans called for a morlel, having E true-contour f1a.T with a traflfng edge 8ngle of lL,6 an? two bevele2 flaps with trailing-edge angles of 20“ and 50, Eecause of the diff3.e culty of working the thin woodon trailing edge, these angles were not obtained exactly, The fXa? with airfofl contour

13、 had, by aeasurement of the model, an included angle of 1. The test Reynolrls number was 2,400,me based or1 the moqel mean aerodynamic chord of 2,Og feet. The effective Reynol3.s number (for maximum lir“t coefficlent) was a?p?oxfmatel;: 2,730,000 based on a turbulence fzctor of 1.93 for this tunnel,

14、 Tunnel-wall corrections, theoretically determined according to the method given in reference 7, were apglied to the data, No correctims were made for the effect of gclp between the root section and the tunnel wall or the leakFge around Qhe supporting torque tube, The correctfcns appllefi (by aclcii

15、tiDn) to tke txnnel data were as follows: where C Is the total uncorrecte3 lift coefficient, =T Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA TN No, 1248 7 fs the uncorrected lLft coefficient due to flap deflection, and k is a constant de2gnde

16、nt on the chord of the overhang 8s follows : CLr l3ISCUSSION Lift and (ab) A summary of the lift paraq?eters for the various fley, confLguratlons, as cieterniiie? frm tke lift curves found in figures 5 to 14, is gtven in table III* The effects of overhar,:? pap, an6 treiling- edge angle were, In pze

17、ral, siniilar to the effects that have Seen focnd in tests 3f two-+fmensfonal ciodels (reference 6). fth t,I?e gap sealec?, Fin Increase in mer- an2 is-lally heng had smsll annd irregulw effects on increased (ag) ; whereas, vvftn the gep opxi, an inepease in overhsng reduced CT, and usually S.ncree.

18、sed (ag)Cts were PLrcressed either by sealing Both CLa and (as) the gap or b re whereas the difference In hinge- As has been found in tests of two-dimensional models (reference 8), decrepsing the balmce chord, decrecsing the beveled-traillng-ede angle, rnd, in general, seallng the gpp a.t the flsp n

19、ose made the values of Ch end Ch become more negative (figs, 3 to 14). overhpng , and trpiling-edge angle on summsrized in figure 16, 6 The effects of gap, a are hi end c Chct The effects of the trailing-edge Pngle on the incre- ments of the hinge-moment pargmeters produced by overhang end by gap co

20、nditlon me shown in figure 17. Increases in the trgillng-edge angle tended to decreese slightly but to increrse the the effect of the overhang on C effect on C (See fig. 17(a),) A correletion, presented in reference 9, of drta on several different airfoil sections caused by given overhmgs were very

21、much smaller when the trailing-edge angle WPS imge than when the trailing-edge angle wrs smt.11, The dafx shom In figure 17, however, from thpt shown in show sn opposite effect on AC reference 9. A mutus1 interference apperrs to exfst between the effect of the ovei-h,ong and the effect of the traili

22、ng-edge Pngle, wliich interference mey account in part for the opposite effect on hti indicgted that both the increments ACb pnd AClig xl, ACb shovn in figure L7, Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-The effect of the bevel on the overhang

23、 is to d_eCrease the effectiveness of the overhang because the bevel decreases the negntive pressupe over the portion of the airfoil rherd of the flap hinge (reference 90). The break in the airfoil surface ahead of the overhang, however, creates E, disturbance which thickens the boundary lp.yer at t

24、ho trizilring edge md thareby increeses tho effectiveness of the bevel; the size md loca- tion of the disturbance wd thus iks effect on the boundary- layer thickness depends on the length p,nd shape of the over-. h,qng, The relative magnitude of the effects of the mutizel depend on the particult mod

25、el as 11 as on the trclling- edge mgle* Figure l7(b) show that incre,crses in the trailing-edge mgle increased the increments of Chc, and interference of bevel and overhang on bcha md AChs wtl.1 cnused by unseeXLng the gp, ch5 Figure 18 shows a comparison of the effect an flap hinge-moment coefficie

26、nt of bevel and overhang when found separately and in combination, 2,:xcept at large flap deflections, the increrr,ents of hinGe-mment coefficient caused by the adlition of the effects of overhang and bevel (each deternined se2aratelg) were slightly different from the Increments caused by overhang a

27、nd bevel tested in combination. The difference indicates the small interfer- ence, previously mentioned, of trailing-edge angle and overhang. A comparison of the hinge-moment parameter values for the tapered wing of the ?resent investigation with the values for the rectangular and ell5pt;fcal contro

28、l surfaces of prevfous investigations (references 1 and 2) showed that, in general, the plan form has a snzall and incon- sistent effect. (See fig. 15.) Drag Although the drag Coefficients cannot be considered absolute because of unknown tu-nnel effects, the relative values nay be independent Df tun

29、nel effects. The d.rag- coefficient values as ftlnctions of angle of attack at various flap deflections are shown in figures 3 to lk. In figure 19 the drak coefficient is plotted agafnst tLe lfft coefffcfent with a f= 00 an3 6 varying from Oo to 30 for the plain sealec? flap with three different tra

30、iling- edge angles. The drag coefficients were approximately the Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-10 NACA TW No. la8 saxe for all these arrangements at small lift coefficients and flajj deflections. At large flap deflections the lift d

31、ecreased. with an increase of the trailing-edge angle for approximately the same amount of drag. Pitching hloment (c“CLs and The pitching-moment parameters (table 111) indicate the position of the akrodynarnid center with respect to the 0.40 point of the root chord. i? 1 Values of Finit e- Wing Clia

32、rac t eris t ic s Table 111 presents the lift and hinge-rtloment garamebr values as measured from section data for use in calculatkg finite-span data, as measured from the present experimental data, an3 as calculated for the finite tapered wing from the section data, ?“ne section values for the plai

33、n flap were obtained. from reference 12; the values for the elliptical-nose-overhan flap with, the trailing-edge angle for tunnel effects, before the finite-span parameters were calculated, fn a manner similar to the method presented In reference 7. The aedium nose referred to in reference 8 had the

34、 sane nose shape as the elliptical nose teste3 in the present investigation. Since the section data for the elliptical-nose-overhang flaps with trailing- edge angles of l9.8O and Z9.6O were not available, the parameter values were obtainec? by the addition of the increment caused by the effect of th

35、e overhang to the values for the plain flap with beveled trailing edge; any interference between the effects of trailing-edge angle and the effects of overhang have therefore been neglected in estimating the aero4ynamic section parameters. of 11.1O were obtained f rom reference 8 and were corrected.

36、 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA TN Mo, 1248 11 Lfftfng-line theory was used to calculate the lift and hinge-moment parameters from section clata according to the methods suggested in references 4 and G* The Jones edge-velocity c

37、orreccion tu the lifting-line theory (reference 3) was applied in the computation of Cz, with the substitution of values for E for the elliptical 3Lan form of the same aspect rstfo, where E is the ratio of the serdperfmeter to the s2an, The method developed in reference 5 for use OE a wing of ellipt

38、ic plan form was applied fn calculating the lift and hinge-moment parametem according to lifting-surface theory. In most cases, values of tke lfft parameters (table IIT) and of +,he hinge-moment parameters (table 111 and fig. 20) calculated by lifting-surface theory agreed more closely with the meas

39、ured values than did values calculated by lifting-fine thew$ wSth the Jones edge- velocits correct ion applied. Cifferences between the measured values of the lift and hinge-rxoment parameters and values calculated by lifting-surface theory were, in general, no greater than the differences noted in

40、figure 15 between the rneasarsd values for wings of the same aspect ratio but wi%h different chord distrZbution8, For the flap with overhang, lifting-lfne-theory calcu- latfons of the hinge-moment parameters shmed almost as good agreement wPth the izeasuyec? values as lifting-surface- theory calcula

41、tions. It appears that lifting-surface theory gives closer agreemen5 between. calculated and measured values for than for ch6. ha G ONCLYS f OWS The results of the present tests in three-d-lmensional flow of an NACA 0009 tapered semispan wfng and a comparison with Iff% and hinge-moment parameters ca

42、lculated from two- dimensional-flow Ctata of previous investigstions indicated the following conclusions : I, The effects of overhang, ga2, and trailing-edge angle on lift and hinGe-mornent parameters were, in general, sfmilsr to effects which pxviously had been found in testa of two-dimensional mrJ

43、.els. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-12 NACA TN No, 1248 2. Interference between trailing-edge angle and overhang was indicated by the fact that the incremental effects of the overhang on the binge-moment parameters varied as the tra

44、iling-edge angle was increased. 3. Eifferences between the measured values of the lift and hinge-rcornent parameters and values calculated from two-dimensional data by lifting-surface theory were, in general, no greater than the clifferenee between the measured values for wings of the same aspect ra

45、tio but with different chord. distrPbutZons. Langley Memorial Aeronautical Laboratory National Advi s ory Conmii t t ee for Aeronaut ic s Langley Field, Va., April 2, 1946 P Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA TN No, 3.h, Bernard J+,

46、 and Silvers, B, fuorman: WTnd-Tunnel Investigation of Control- Surface Characteristics of Plain and Balanced FZETS on 3ii MXA 0009 Elliptical Semispan Wing. NSGQ LLRX RO, LLX, 19.i.6, 1qL1, 3. Jones, Robert, T.: Correction E? the Lifting-Line Theorby for the Effect of the Chord. 4. Swanson, Robert

47、S., and Gillis, C1c.Llence Le: NAGA TN No, 817, Limitations of Lifting-Line Theory fop Estimation of Aileron Hinge-Moment ChmactoristLcs e NbCA U3 No. 3L02, 1943. 7. Swanson, Robert S., and Toll, Thonias A*: Jet-Boundaqy Corrections for Heflcction-Plane Models in Rectangulw Wind TtmneLs. NACA ARR 80

48、, 3322, 1943. Characteristics of X.rplano Control, Surf aces e f 8. Sears, Richard I, : IYhd-FCunnol Data on the NACA ACR NO, 3LtU8, 1943, Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-14 XACA TI? No, la8 10. Hoggmd, H, Page, Jr, QR A=3. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Fig. 3 cont. NACA TN No. 1248 . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,