1、RESEARCH MEMORANDUM f. 5 DEC 1947 YAW CHARACTERETICS AND SIDEWASH ANGLES OF A 42 SWEPTBACK CIRCULAR-AEC WSNG WITR A FUSELAGE AWD WITH LEADING-EXE AND SPLIT FLAPS AT A REYNOLDS NUMBER OF 5,300,OOC By Rein0 J. Sahi and James E. Fitzpatrick Langley Memorial Aeronautical Laborst tory Langley Field, Va.
2、“ NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS WASHINGTON December 10, 1947 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-i By Reino J. Salmi and Jams X. Fitzpatrick . An investigation of the low-aped aerodynamic characteristics in yaw of a 42O swep
3、tback wing of circular-arc airfoil sections waa conducted in the Langley 19-foot pressure tunnel. The wing haid an aspect ratio of 3.94, taper ratio of 0.65, an3 neither dihedral nar twist. The teste were made at a Reynolds nmber of 5,3OO,OOO and a Mach number of 0.11 and included the effect8 of lea
4、ding-edge flaps an3 split flaps and of a fuselage with the wing munted tn high and low posltions. Th3 results of the tests showed that the dihedral effect of the plain wing was maximmu at a lift coeff icient of 0 35 anhro the qwter-chord poht of :.he mec% aerodynmlc chord. The pitchfng-moment data f
5、or the wing lone are referred tc the quarter-chord point of the mean aerodynamic chord pl-ojecteci to the plane of symmetry. Standard NACA sym3ols ere used, filch axe defhed as ?ollowe: c4Rsx maximum lift coeff Zcient Provided by IHSNot for ResaleNo reproduction or networking permitted without licen
6、se from IHS-,-,-NACA RM NO - 7130 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM NO. L7130 Mean aerodynamic chord (MOA .c .), measured parallel to plane local chord parallel to plane of eymsletry free-etream dynamic pressure (5$) dynamic p
7、ressure at tail free- s tream velocity ma88 deneity of air Reynolds nmbr (pVz/cl) coefficient of viscosity of air Mach number (V/a) velocity of sound hefght above fuselage center line, fraction of M .A.C . longitu3lnal distance frm center of gravity to center of preesure of vertical tail rate of cha
8、nge of yawing-mament coefficient vfth angle of yaw, due to vertical tail .lift-curve slope of vertical tail APPARATUS .4mD TESTS Model Figure 2 shows the details of the model. The whg has a sweepback angle of 42.05 dong 9. Line joining the lea- edges of the mot chord and the theoretical tip chord. T
9、he aspect ratio ie 3.94 and the taper ratio, 0.625. There is no geometric dihedml nor twist. The Ftirfoil sections normal to the line of maximum thickueser are symmetrical circular- that ie, the vortices from the leading wing influenced the aide flow while those from the trailing wing were caxried d
10、ovnetream. A prevloue eibe-flow Inveatl- gation (reference 5) pointed out that the vortices associated xith the span load distributian of the wing of conventional sectlone and low sweep made a practically negligible oontribution to the sidewssh angle. However, the.gresent investigation imlubeb tests
11、 of a wing of lower aspeut ratio thus stronger and cloeer to the aurvey plane. . and of circular-am sections at Mer lifts. The wing vortice8 -re At the hi hence the aidemah i8 less negative than for the fueelage alone. 9 . The reeults of the present investigaticm seem to verify the preceding analysi
12、s Figures 12(a) and 12( b) show a close similarity of the sidewash angles for the wing alme and for the high-wing combination. The inter- ference thus appeara to cancel the fuaelwe effect, and the sidewash behind the high-wing cambination 18 due -st entirely to the wing-vortex field described in the
13、 preceding section. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-12 NACA RM NO * L7I30 On the other hand, the large negative eidewzuih ernglee of the low- wing combination ( fi ge. ll( b) and 12(c) ) indicate that the combined effects of the melag
14、e vortioee and wing.fuselage interference are large. The greater negative eidewaeh anglee behind the low-wing combination would increase vertical-tail effectivenees but would cause vertical-tail stall at lmr anglee of yaw. The average valuee Of sf ab obtained were frara -0.2 to -0.3 in the low-wing
15、configuration and From 0 to -0.1 in the high-wing combination. The -paee of negative aidewash near the fuselage in the low-wing cc. +Yguratib (fig. 12(c) would Increase the effectiveness of a dorsal fin ,n this configuration over that in the hfgh-wing canfiguration. Figure8 12( b) and Il(a) indicate
16、 a sudden diminution in dynamic pressure at the high angles of attack In the high-wing configuration. JFrom the gemtry of the wfisreae for the ZBACA 6+112 wing, the effective dihedral increased continuously up to the maximum lift With leading-edge flape, there was negligible difference in the variat
17、ion of effective dihedral with lift cmfficient for the two wlnge. 8. he results of the air-stream surveys showed that a vertical tail and dorsal fln would be more effective cm a low-wing airplane of this type than 011 a corresponding high-wing airplane. Langley-Memorial Aeronautical Laboratom Nation
18、al Advisory Committee for Aeronautics Langley Field, Va. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3.4 NACA m NO . 7130 1. Neely, Robert H., and Koven, William: Low-Speed Characteristics in Pitch of a 42O Sweptbwk Wing with Aspect Ratio 3.9 and
19、. Circular-Arc Airfoil Sections. NACA RM No. L7H23, 1947. 2. Eieenetadt, Bertram J.: Boundury-Induced Upwash for Yawed and Swept-Back Wings in Closed Circular Wind Tunnels . RACA Tm No . 1265, 1947 3 . House, Rufus Om, and Wallace, Arthur R. z Wind-Funnel Investigation of Effect of Interference an L
20、ateral-Stability Characterietice of Four WA 23012 Wnger, en Elliptical and a Circular Fuselage, and Vertical Fine . IJACA Rep. No. 705, 1941. 4 Salmi, Rein0 J., Comer, Dm William, and Grabam, Robert R . : EPfecte of a Fuselage on the Aerodynamic Charrtcteristics of a 42O SweptbcLck Wing at Regnalds
21、Numbers to 8,000,000 NACA RM No. L7E13, 1947. 5 Recant, Isidore G., and Wallace, Arthur R . : Wind-Tunnel lnveeti- gation of the IWfect of Verticd Poeitian of the Wing on the Side Flow in the Ream of the Vertical Tail. NACA TN Bo. 804, 1941. Provided by IHSNot for ResaleNo reproduction or networking
22、 permitted without license from IHS-,-,-9. Configuratlon Wing alone, flap on Low wing, flaps on High wing, flaps co1 Low. wing, fhps off a 5 -9 15 .3 3.6 n.1 17 -4 3.6 I1 01 17 -4 5 -4 14 -3 5 -4 14.9 I av (sed -0.3 - .9 -1 -3 -3 -4 .2 -1 .5 -2 -6 -4 .4 -2.2 -3.1 -4 05 -1.4 -3 04 -6 -4 - 04 - -3 -1
23、-2 - .2 - -8 -2 -2 - -3 -I -2 -2 00 - -9 -2 -3 -3.1 -1.3 -2 .g -4 03 - 02 - 07 -1 -2 . .I - .I - -4 )RY COMMITTEE FOR AERONAUTICS Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. . . . . . . Provided by IHSNot for ResaleNo reproduction or networking
24、 permitted without license from IHS-,-,-. NACA RM No. L7I30 F = 35.31 in.; aspect rafa = 3.94. No dbedmi of twist. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-18 NACA RM No. L7I30 Provided by IHSNot for ResaleNo reproduction or networking permitt
25、ed without license from IHS-,-,-. NACA RM No. L7I30 (a) Model installation. 19 Figure 4.- The 42 sweptback wing of symmetrical circular-arc sections mounted in the Langley 19-foot pressure tunnel. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provi
26、ded by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM No. L7I30 21 (b) Details of leading-edge flap. Figure 4.- Continued. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-4 Provided by IHSNot for ResaleN
27、o reproduction or networking permitted without license from IHS-,-,-NACA RM No. L7I30 (c) Support-fairing details. Mgure 4. - Concluded. 23 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or networking per
28、mitted without license from IHS-,-,-NACA RM No. L7130 25 COYMTTEE FOR AERONAUTICS 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-,-,-. NACA RM No. L7130 ”
29、I- V 5echn A -A NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS (e) Locution of air - stream survey poinfs. 27 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-F splif flops deflecfed ; and 055i and 0.70# led- edw flaps in 5 conjumtbn with splif flws deflecfed . 0 I . . . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
