1、W-d -NATIONALADVISORYCOMMIITEEFOR AERONAUTICSTECHNICAL NOTE 3497/SUMMARY OF RESULTS OF A WIND-TUNNEL INVESTIGATION OF NINERELATED HORIZONTAL TAILSBy Jules B. Dods, Jr., and Bruce E. TinlingAmes Aeronautical LaboratoryMoffett Field, Calif.WashingtonJuly 1955Provided by IHSNot for ResaleNo reproductio
2、n or networking permitted without license from IHS-,-,-TECfILIBRARYKAFB,NM.N 111111111111NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS QQbb545- -TECHNICAL NOTE 3497SUMMARY OF RESULTS OF A WIND-TUNNEL INVESTIGATION OF NINERELATED HORIZONTALBy Jules B. Dods, Jr., andSUMMARYTAILS1Bruce E. TinlingThe resu
3、lts of a wind-tunnel investigation of a series of models ofnine related horizontal tails have been summarized to provide basic designinformation; to indicate the effects of aspect ratio, sweepback, andchanges in the Mach number; and to provide experimentalvalues of the liftaridhinge-moment parameter
4、s for comparison with values computed by amethod employing lifting-surfacetheory. The models had aspect ratiosfrom 2 to 6, angles of sweepback of the quarter-chordline from 5.7 to45, a taper ratio of 0.5, and had 30-percent-chord,sealed, plain flaps.The Mach number was varied from 0.12 to 0.94 for R
5、eynolds numbers of 2,3, or 4 million. Also, a constant-chordairfoil having the NACA 64AO1Osection and completely spanning the wind tunnel was tested at a Mach numberof 0.12. This airfoil had the same section and flap-chord ratio as thenine horizontal-tailmodels.Satisfactory correlation was obtained
6、between the low-speed experi-mental values of the lift and hinge-moment parameters and the computedvalues. Extension of the method employing lifting-surfacetheory to highsubsonic Mach numbers through an application of the Prandtl-Glauert ruleyielded variations of the lift parameters with Mach number
7、 which were ingood agreement with the experimental results at Mach numbers less than thatfor lift divergence. The predicted values of the hinge-moment parameters,however, did not agree with the experimental results at Mach numbersapproaching the divergence Mach number.INTRODUCTIONAn investigation of
8、 the aerodynamic characteristics of horizontaltails has been undertaken by the NACA to provide basic design informationlSupersedesrecently declassified NACA RM A51G31a by Jules B.Dods, Jr., and Bruce E. Tinling, 1951.Provided by IHSNot for ResaleNo reproduction or networking permitted without licens
9、e from IHS-,-,-1L NACA TN 34q7and to provide experimental results which could be used to determinethe accuacy of theoreticalprocedures for estimating the lift andhinge-moment parameters. References 1, 2, and 3 have presenteddetailed results of tests, conducted in the Ames 7- by 10-foot windtunnels a
10、nd the Ames 12-foot pressure wind tunnel, of a series ofhorizontal-tailmodels having aspect ratios from2 to 6 and eitherhaving the hinge line normal to the plane of symmetry orhavirig 35or 45 of sweepback of the quarter-chord line. A comparison of thelift and hinge-moment parameters evaluated from t
11、heory with thoseobtained eerimentally was presented in reference 4.The purposes of the present report are: to combine the basicdesign information available in references 1, 2, and 3; to sumarizethe experimentaland the theoretical variations of the lift and hinge-momentand tometersClzeCheCLcli!qparam
12、eters with aspect ratio and sweepback at a low Mach number;show the effects of changes of the Mach number on these para-for three of the models.NOTAITONCoefficientselevatorhinge-gmnent coefficient ( )elevator hinge moment 2qMA /sectionhinge-moment coefficient ( )section hinge moment()liftlift coeffi
13、cient _qssection lift coefficient (section lift)pressure coefficientacross the elevator nose seal( ressure below seal ) free-stream dynamic pressure.-wProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA TN 3497SymbolsAabbtcc.CefMl-lAaspect ratio():.
14、54.566Sweepback(35:05*735.0Hingeline .3;.12;.638.7029.53:.0Hinge-bracket location, percent I7- -bylo-footwind-tunnelmodelsE8282ii828238 snd 82xl I12-foot pressurewind-tunnelmodels I- - I- - I- - I- - 1“50,2 and 90.628, 81 and 9534, 80 sxK196- - I- - 1The geometry of each model is,shown in figure 1.
15、In addition tothe horizontal-tail models, a 3-1/2-foot-chordairfoil with no sweep-back that completely spanned the 7-foot dimension of the 7- by 10-footwind tunnel was tested. This airfoil had the NACA 64AO1O section anda 30-percent-chord,sealed,plain flap. The coordinates of the NACA64AO1O airfoil
16、section are yresented in table I. The horizontal-tailmodels which had no sweepback of the hinge line had the I?ACA64AO1Osection parallel to the plane of symnetry. The horizontal-tail modelswhich had either 35 or 45 of sweepbackhad this section perpendicularto the sweep reference line. The sweep refe
17、rence line was chosen asthat line which joined the quarter-chordpoints of the NACA 64AO1O air-foil sections; The models with the hinge line normal.to the plane ofsymmetry (referredto in this report as the unswept models) had somesweepback of the sweep reference line. To be strictly consistent, theNA
18、CA 64AO1O airfoil sections should have been placed normal to thesweep reference lines of the unswept models. However, since the angleof sweepback involved was small, the aerodynamic effects resulting fromthis inclination of the NACA 64AO1O airfoil section to the sweep refer-ence line were probably n
19、egligible.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-:.The tip shape of eachsection about a chord linehalf the ms,xirlumthickness.!ACTJ3+7model was formed by rotating the airfoilinboard of the tip a distance equal to one-of the tip airfoil secti
20、on.All the models had 30-percent-chord,sealed, plain elevators andtwo of the models (fig. l(e) were equipped with tabs. The 30-percent-,chordratio of the elevator was maintained in the planes of the NACA64.AO1Oairfoil sections. The details of the elevator balance chambersare shown in figure 1. The e
21、levatorhinges divided the balance chaniberinto separate sections. Seals were fitted closely at the ends of eachsection to reduce the leakage to a minimum.TESTS:;adelsof all the tails, with the exception of the tail having anaspect ratio of 3 and 45 of sweepback,were tested at low Mach numbersin the
22、Ames 7- by 10-foot wind tunnels at a Reynolds number of 3 million.The tests in the Ames 12-foot pressure wind tunnel of the horizontal-tail models having an aspect ratio of 4.5 were conducted at a Reoldsnumber of 2 million, and the tests of the model having an aspect ratioof 3 and 45 of sweepbackwer
23、e conducted at a Reynolds nuniberof 4 mil-lion. The maximum test Mach numbers were 0.88 and 0.94 for the unsweptand the swept-backh-orizontaltails, respectively.The semispanmodels were mounted vertically with the wind-tunnelfloor serving as a reflectionplane as shown for typical models infigure 2. T
24、he turntablesupon which the models were mounted weredirectly connected to the force-measuringapparatus. The elevatorhinge moments were measured with resistance-typeelectric strain gageswhick were beneath the turntable cover plates.CORRECTIONSAll the data have been correctediterfernce.The corrections
25、 to theTO DATAfor the effects of tunnel-walldata from the 7- by 10-foot wind.wtunnels were computedby the methods of references 5 and 6. The cor-rections to the data from the 12-foot -pressurewind tunnel were computedky tke methods of references 7 and 8. In the application of the methodf reference 7
26、, the theoretical span loadings for incompressible flOWwere calculatedby the method of reference 9.a71a15Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA TN 3497 7RESULTS AND DISCUSSIONThe results of low-speed tests of the 3-1/2-foot-chordairfoil
27、having the NACA 64AO1O section and having a 30-percent-chord,sealed,plain flap are presented in figure 3. The results of tests of the ninerelated semispan model horizontal tails having the same airfoil sectionand differing only in aspect ratio and sweepback are presented infigures 4 to 20. The lift
28、and hinge-moment characteristics are sum-marized in figures 21 to 24. The effectiveness of a tab in reducingthe elevator hinge moments for a range of Mach numbers is presented infigure 25 for the models having aspect ratios of 4.5. An index of thefigures presenting the results is given in the append
29、ix.Information not presented herein but which is available in refer-ences 1, 2, ani3 shows the effects of standard leading-edge roughnesstineeffects of removal of the elevator nose seal, the effects of varia-tion of the Reynolds nuniber,and the pitching-moment characteristics.In addition, the drag c
30、haracteristicsare available in references 2 and3 for the three models tested in the 12-foot pressure wind tunnel. Thepressure distribution at the midsemispan and the tab hinge moment havealso been given in reference 2 for the two models having an aspectu ratio of 4.5.The following discussion covers
31、first the effects of sweepback andJasrect ratio at a low Mach number, and then the effects of changes ofth Mach number for the three mod=ls which were tested throughout thesubsonic Mach nuniberrange.Effect of Sweepback and Aspect Ratio at Low .MachNumbersLift and hinge-moment parameters.- The data p
32、resented in figures 3through 11 were obtained in the 7- by 10-foot wind tunnels. Theseresults are summarized in figure 21 to show the effects of variationsof sweepback and aspect ratio upon the lift parameters CL and C. sa Lband on the hinge-moment parameters Cha and C%“ For convenience,the numerica
33、l values are also listed in table II. These data sumarizedin figure 21 and presented in table II were obtained at low subsonicachnumbersc Because ofthe nonlinearities in the lift and hinge-moment data, the slope parameters are valid only for a small range ofangles of attack and of elevator deflectio
34、ns near OO. The theoreticalvalues presented were calculatedby the method recommended in reference 4.The correlationbetween the parameters as evaluated from theory and by. experiment is considered to be reasonably good. As shown in figure 21,the iift and hinge-moment pareters have an orderly variatio
35、n with.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-8 NACATN 3497both aspect ratio and sweeback. The lift parameters CL and C%increased as the aspect ratio was increased and were redued in magni-tude as the angle of sweepbackbecame larger. The num
36、erical values ofthe hinge-moment parameters C% and C% became more negative withincreasing aspect ratio. The numericalvalues of Cmore negative with increasing sweepback. % also becameThe values of Cha, however,were reduced in magnitude with increasing sweepback. The experimentallift and hinge-moment
37、parameters from the Ames 12-foot pressure windtunnel for Mach numbers comparable to those of the 7- by 10-foot windtunnels are listed in table 11. The lift and hinge-moment parametersfrom the Ames 12-foot pressure tunnel are in satisfactory agreementwith those from the 7- by 10-foot wind tunnel with
38、 the exception ofthe value of Ch forthe unswept model having an aspect ratio of 4.5.This differenceetween the values of C% from the two facilitiesexists only at angles of attack near zero. Between 2 and 4 angle ofattack, the value of is -0.0020 from either wind tunnel (figs. 8(b)and 6(a).Pressure co
39、efficientsacross the elevator nose seal.- The pressurecoefficientsacross the elevator nose seal yresented in parts (c) offigures 3 to 11 are useful in the design of sealed, internalj aero-dynamicallybalanced elevators.1 The rate of change of pressure coef-ficient across the elevator nose seal with e
40、levator deflection wasnearly independentof aspect ratio for both the unswept and the swept-back horizontal-tailmodels. A sizable differencewas noted, however,in the rate of change of pressure coefficient across the elevator noseseal with elevator deflectionbetween the unswept and the swept-backmodel
41、s. For example, it was about 25 percent less for the models with350 of sweepback than for the models without sweep. FroI.uthe limitedinformation available for the 45 swept-backmodel it appears that anadditional 15-percentreduction shouldbe expected at this higher angleof sweepback. The models withou
42、t sweepbackhaving aspect ratios of 3,4.5, and 6, and also the swept-hackmodel having an aspect ratio of 6tested in the 7- by 10-foot wind tunnels had alnqt losses of balancingpressures at moderate elevator deflections. (See figs. 6(c), 8(c),1O(C), and 11(c).) The reason for these losses of balancing
43、 pressureis not known. Tests in the 12-foot pressure tunnel ofthe models havingaspect ratios of 4.5 did not show such an abrupt loss of balancing pres-swe. Attempts to explain this discrepancyhave shown that it cannotbe definitely ascribed to the difference in balance-chambervolumes orto the nuniber
44、of compartments in the balance chambers.or a discussion of the design procedure see reference 10.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-ANNACATN 3497 ., 9Effects of Mach NumberThe results of tests of three models in the Ames 12-foot pressure
45、wind tunnel are presented in figmes 12 to 20. The variations of thelift and hinge-moment parameters CLas cLunswept CL vs a .14 4(a)1Che vs aI4(b)A, 45 CL vs a 5(a)1Che vs a 5(b)AP/q vs se 5(c)A,3;unswept CL VS .7 6(a)1evs aI6(b)A ,35 CL vs a 7(a)/Che VS a 7(b)AP/q VS be 7(c)A,4.5;unswept CL vs a .21
46、 8(a)!Che vs a1 . v8(b)A, 35 CL vs a 9(a)1Che vs a 9(b)Ap/q Vs be 9(c). .Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-12 NACA TN 3497LIFT AND KCNGE-MOMENT CKARACT!ERISTICS(CONTINUED)ModelA,6;unsweptIA,6;A,37IA,3;A, 43vA.4.5;unsweptResultspresented
47、CL V aChe vs aAp/q vseCL vs aChe vs aAP/q VS BeCL Vs alIe Vs a!AP/q VS seICL VS aIChe vs a1M0.23I.25.60.80.85.90, .92.94.25.60.80.85.90.92, .94.25.60.80.85a71 90,.92, .94.21*6Q,80.85a7188.21:Z.85*88(dion)3.014.02.0Figurenumber10(a)10(b)lo(c)U(a)n(b)11(C)12(a)12(b)12(C)12(d)12(e)13(a)13(b)13(C)13(d)I
48、s(e)13(f)14(a)lb(b)14(C)Ik(d)14(e)15(a)15(h)15(C)15(d)15(e)16(a)16(b)16(c)16(d)16(e)Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-XACA TN 3497.wLIFT AND HINGE-MOMENT CHARACRISCS (CONCLmED)Model Results M Figurepresented (mil?ion) numberA.h.5;unswept 4?/q s ae 0.21 17(a)J I z 2“0 17(e)17(b)17(C)17(d)A,4.5;A,35 CL VS a .21 18(a)I a7160 18(b),83 18(c).90 18(d)93 18(e),94 18(f)Che vi Ct ,21 19(a)!.60 19(b).85 19(C).W 19(d)a71 93 19(e).94 lg(f)Ap/q Vs 8e .21 20(a)v !.60 20(b).85 20(C)
