NASA NACA-RM-L8I03-1948 The effects of high-lift devices on the low-speed stability characteristics of a tapered 37 5 degree sweptback wing of aspect ratio 3 in straight and rollin.pdf

1、Copy No. 134 FCM No. L8103 RESEARCH MEMORANDUrvr- THE EFFECTS OF HIGH-LIFT DEVICES ON TIZZ LOW-SPEED STABILITY CHARACTERISTICS OF A TAPERZD 37.5 SWEPTBACK WING OF ASPECT FZATIO 3 ti STRAIGHT AND ROLLING FLOW BY M. J. Queijo and Jacob H. Lichtenstein Langley Aeronautical Laboratory Langley Field, Va.

2、 w “G- 4 bq, a i oVNILBA DoC!ntmmtA DAtAd Prior to January 1, 1960 z Mover , until me#lrts, Researeb Authorizationa, eorro8pondonce, ph.OtogtAphS And other dOet8nOitatiOn. Earlfor, in 020,000, respectively. The results of the investigation indicate that the variation of the parameters with lift coef

3、f.icient is essent the same at low and moderate lift coefficients for all the conflgu2ations tested. The high-lift devices extended the initial trend of the derivatives to higher lift coefficients, and Fn some case8 also caused smaJJ. displacements of the curves plotted against lift coefficient. Ros

4、e flaps w-ere not as effective as slats inextendlngthe initial trendof the curves tohighlift coefficients. Combinations of split flaps and slats produced effects which were approximately equal to the sum of the effects of spLLt flaps alone and slats alone. Estimation of the dynamic fli L8IO3 C and s

5、ljlit flaps (fig. 3). All slats had chords which were 10 percent oe.tie wing chord (measured IIEJJ to the wing quarter- chord line) and all split flaps had chords which were 20 percent of the wing chord (normal to wing quarter-chord line). The slats were made by l 1 Provided by IHSNot for ResaleNo r

6、eproduction or networking permitted without license from IHS-,-,-S based on-unstiept-*tie theory, for the effects of the ilet .boUnaar+$ baveez,en applied ,taq.,w and the roJUng derivatives Cz pf %lg - cyp are presented in figures 12, 13, and 14, respectively. The data for the 10 model configuration

7、s are divided into three groups.in each ?i,gure. The groups are (1) wing with split flaps, (2) winewith slats or nose flap, and (3) wing with combi- nations of split flaps and slalq. The charaoteristico of the plain wing are included in each 09 the groups in order to provide a basis for com- parison

8、 witLresults obtained with various high-lift devices installed. Characteristics of PlM.r.Wing The characteristics of the plain wing generallg were good in that there werd no abrupt.cerivativer3at modgrlir_i;e lift coefficienti. The more favorable characteristics oethe present wing probably are a res

9、ult- of the moderate sweep angle in combination with a low aspect ratio. The pitchLngplomen$ curve of figure 8 is esgentially linear up to the stal.landhU a atable breakatthe stall. The effective dihedral parameter Cz $ increased linearly with lift coefficient up to approximately tiimum iift (fig. 9

10、) and then decreased very rapidly beyond tiimum lift. The directional stability of the Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM No. L8IO3 7 c Y c model C, If increased approximately as the square of the lift coefficient (fig. 10) as mi

11、ght be expected from the theory of reference 5. At about the maximum lift coefficient, C, f broke in a positive direction. The ds3npinSinrol.l Cz P (fig. 12) showed some increase with lift coefficient snd, although this trend is not indicated by theory been observedin other tests of swept wings (ref

12、erences 4 and 6j. it has Nega - tive damping ( positive CL was obtained beyond msximm lift, indicating that the model would autorotate if it were free to rotate. The yawing moment due to roll c“p was negative at all lift coefficients below maximum liftbut became positive beyond maximum lift (fig. 13

13、). Some of the important measured derivatives of the model are seized in table I. The experimental results are csed with the approximate theory of reference 5 and, where possible, with the theory of Weissinger (references 7 and 8). The ccznparison betweentheory and experiment Sener- ally is consider

14、ed to be fair with the excsption of ca/cL- The differ- ence between the theoretical snd measured values of %P probab1y Is caused by the wing-tip suction forces associated with asymmetric load conditions. Such forces were not accounted for in reference 5. Refer- ence 9 indicates that good agreement b

15、etween theoretical and measured values of C %I CL might be obtained if the tip suction forces were accounted for. Effects of Split Flaps The O.Y-span and l.O-span split flaps produced lift-coefficient incre- ments of about 0.33 and 0.48, respectively, and these increments remained approx.imately con

16、stant, even to the maximum lift coefficient. Tests of other swept wings (references 1 and 10) have indicated that flap effective- ness in producing lift generally decreases with increase in lift coefficient. Split flaps increased the longitudinal force very appreciably and made the pitching moment m

17、ore negative. The alsince the addition of split-fh3pswoul.d be expected to have little effect on either the maatude or the location of the center of pressure oftha incremental load caused by roll3n.g. For the model investigated, the additionof split flapsinvariably cause-d an extension to higher lif

18、t coefficients of the trends in the derivatives that-were noted at low lift coefficients for the plainwing. Effects of Slats end Nose Flaps The addition of slats or nose flaps caused the lift curve to be extended to higher angles of attack, thus providing increments in maximum lift coefficient amoun

19、ting to 0.18 for the 0.5-apan slat, 0.39 for the l.O- span slat, and 0.27 for the X.0-span nose flap. Thenoseflapandslats tended to move the aerodynamic center slightly forward, as is indicated by the decreased negative slopes ofthe pitching-moment curves (fig. 8). A forward shift in aerodynamic cen

20、ter would be expected since the nose flap and slats effectively extend the l however, the nose flap was not as effective as the slats in maintame the linear trends to higher lift coefficients. A relatively large displacementj in a negative direction, of the +-curve reeulted. * from the additionof th

21、e l.O-span slat. The slats axd nose flaps caused small increases in the dsmping in roll r egative Cz 1 atmoderatelift P coefficients .Thie probably resulta from the effective increase in wing area that accoeed the addition of either the nose flaps or slats. . - Provided by IHSNot for ResaleNo reprod

22、uction or networking permitted without license from IHS-,-,-Effects of Combinations of Split Flaps and Slats In general, combinations of split flaps and slats had two major effects on the wing characteristics. One of these effects was the exten- sion of the linear portion of the curves of wing chara

23、cteristics to higher lift coefficients, and the other effect was the displacements of some of the curve8. The data of figures 6 to 14 indicate that these extensions and displacements are approximately what would be expected from the results obtained for the effects of split flaps-alone ti slats alon

24、e. Figure6 indicates that the combination of the wing with l.O-span slats and 0.5-span split flaps produces very nearly the same meximum lift coefficient as the wing with I-O-asan slate and l.O-span Split f7apSj however, the pi&ling- moment variation at the stall is not as satisfactory for the forme

25、r combination as for the latter combination, .An effect shown by the combi- nation of split flaps and slats (not shown by slats alone or split flaps alone) is the change in 1ift:curve slope at low lift coefficients for some of the configurations (fig. 6). It is believed that the increase in damping

26、in roll at low lift coefficients of some of the configurations (fig. 12) is associated with the changes in the lift-curve slope. cONCLuS10NS The resulta of tests made to determine the effec_ts of high-lift devices on the stability parameters of a tapered 37.5” sweptback wing of aspect ratio 3 in str

27、aight and rolling flow have led to the following conclusions: 1. The variation of the parameters with lift coefficient is essentiaXLy the same, at low and moderate lift coefficients, for all the configurations tested. 2. The high-lift devices extended the initial trend of the parameters to higher li

28、ft coefficients and in some cases caused small displacements of the curves plotted against lift coefficient. 3. Nose flaps were not as effective as slats in extending the initial trend of the curves fo high lift coefficients. 4. Combinations of split flaps end slats produced effects which were appro

29、ximately equal to the sum of the effects of split flaps alone and slats alone. . c Langley Aeronautical Laboratory Rational Advisory Carmnittee for Aeronautics Langley Field, Va. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-10 NACA m HO. L8103 REF

30、ERENCES 1. Lichtenstein, Jacob 3.: Effect of 3Xigh-Lift Devices on the Low-Speed Static Lateral Stability and Yawing Characteristics ofan Untapered 45O Sweptback Wing. NACA RM NO. L&ZO, 1948. 2. MacLachl.&, Robert, and Letko, Williem: Correlation of Two Experimental Methods of Determining the Rollin

31、g Characteristics of Unswept Wings. NACA TN No. 1309, 1947. 3. Bird, John D., Lichtenstein, Jacob H., and Jaquet, Byron M.: Investi- Sation of the Zafluence 0fEuselage and Tail Surfaces on Low-Speed Static Stability and Rolling Characteristics of a Swept-Wing Model. NACA RM No. L7Hl5, 1947. 4. Feige

32、nbaum, David, and Coodmm, Alex: Preliminary Investigation at Low Speeds pf Swept.Wings in Rolling Flow. -NACA RM No. Lmg, 1947. . -.- 5. Toll, Thomas A., and Queijo, M. J.: Approximate Relations and Charts for Low-Speed Stability Derivatives of Swept Wings. 1948. NACA TN NO. 1581, 6. Emiton, Lynn W.

33、, and Dew, Joseph K.: Measurements of-the Damping in Roll of Large-Scale Swept-Forward and Swept-Back Wings NACA RM No. Amll, 1947. 7. DeYoung, John: Theoretical Additional Span Loading Characteristics of Wings with Arbitrary Sweep, Aspect Ratio, and Taper Rat-lo. NACATN No. 141, 1947. 8. Van Dorn,

34、Nicholas H., and DeYounS, John: A Comparison of Three Theo- retical Methods of Calculating Span Load Distribution on Swept Wings. NACA TN No. 1476, 194-j. 9. Brewer, Jack D., and Fisher, Lewis R.: Effect of TaperRatio on the Low-Speed Rolling Stability Derivatives of Swept and Unswept Wings of Aspec

35、t Ratio.2.61. NACii RI4 No. L&B, $948. 10. Salmi, Reino J., and Fitzpatrick, James E.: Yaw Characterietias and Sidewash Angle8.of.a 42* Sweptback Circular-Arc Wing with a Fuselage and with Leading-Edge and SplieFlaps at a-Reynolds Number of 5,300,ooo. NACA RM No. L7130, 194-i. Provided by IHSNot for

36、 ResaleNo reproduction or networking permitted without license from IHS-,-,-IUCA RM No. L8103 ll . TABLE1 COMSRISON OF FTH.EPLCIlXKWi Parameters lkgertiental Calculated Calculated (reference 5) (references 7 and 8) . % 0 -053 0.047 0.048 Czq I“ L .0047 -0035 w-B- C % I CL2 -.oa2 -.OOlO -mm czP -.250

37、 -.230 -237 CnP/CL -.Ogo - .047 -m-w , -45 -47 -w-w l Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-12 Figure I.- System of stability axes. Arrows indicate positive directions of forces, moments, and displacements. . Provided by IHSNot for ResaleNo

38、 reproduction or networking permitted without license from IHS-,-,-IBACARMITo. I&E03 l c bmz Gm! 2+ 0.91 25 .74 26 .56 27 28 % 29 5 Figure 2.- Drawing of wing-fuselage combination. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-14 s ecfmn A-A . Figu

39、re 3.- Details of split flaps and slats. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I Figure 4.- Model. configurations tested. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. Provided by IHSNot

40、 for ResaleNo reproduction or networking permitted without license from IHS-,-,-. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACARM No. TBTO? 19 .

41、cc 28 2? 20 16 /2 8 4 0 -4 igure attac a 4 t i iS9 12 6 .4 6. - Effects of high-lift devices on the variation of ano :k with lift coefficient for a tapered 37.50 sweptback wing of . . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-20 NACA RM No. L8I

42、O3 -.6, 4 I I I I I I t I I1 1 i i i i i i i iil -9 -.3 . P I Ii I I I I I I I I I I I nl I I I Figure 7.- Effects of high-lift devices on the variation of longitudinal force with IJft coefficient for a tapered 37.50 sweptback wing. Provided by IHSNot for ResaleNo reproduction or networking permitte

43、d without license from IHS-,-,-NACARM No. L8103 l 21 i .I P I . , T2 Figure 8.- Effects of high-lift devices on the variation of pitching moment with lift coefficient for a tapered 37.50 swepthack wing. . Provided by IHS Not for ResaleNo reproduction or networking permitted without license from IHS-

44、,-,-+ 22 .0/u LV8 .0&s -004 .a?2 .c!m 0 La9 .006 I I I t I. t I Figure 9.- Effects of high-lift devices on the variation of with lift coefficient for a tapered 37.5O sweptback wing. C T * Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUARMNo. L8103

45、 23 H t i i ii i i i i i .002 0 - i i i . Figure 10. - Effects of high-lift devkes on the variation of with lift coefficient for a tapered 37.50 sweptback wing. Cns Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-24 NACA RM No. till03 .a9 -.A24 0 -*c

46、&v -.UU? Figure 11.- Effects af high-lift devices on the variatiQn of CyW with lift coefficient for a tapered 37.50 sweptback wing. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-IIACA RM No. L&O3 25 . t I I t I I I l l nt -2 ,I, t Figure 12. - Effe

47、cts of high-lift devices on the variation of Cz with lift coefficient for a tapered 37.50 Swptback Wing. P Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-26 mc?A-RM No. L8m3 I i i -6 urd l.O-apm slmbm 2 0 T2 l 4 2 n Figure 13. - Effects of high-lift devices on the variation of Cnp with lift coefficient for a tapered 37.50 sweptback wing. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM No. a103 .P n Figure 14.- Effects of high-li