1、Twf No. L7DO8 RESEARCH MEMORANDUM a. PRESSURE-DISTMBUTION MEASUREMENTS ON A FULL-SCALE HORIZONTAL TAIL SURFACE FOR A MACH NUMBER RANGE OF 0.20 TO 0.70 Langley Memorial Aeronautical Laboratory Langley Field, Va. .- NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS WASHINGTON June 25,1947 Provided by IHSNot
2、 for ResaleNo reproduction or networking permitted without license from IHS-,-,-c Surface irregularities were found to cause appreciable dilto- tion of the pressure distribution. The highest crftical speed of the tail surface was 0.77. By eliminatlon of the surface irreguhlt ities, it is estimated t
3、hat this c,ould be increased to 0.80. The rate of charge of pmssure coefficient with angle of attaok over the leading 60 percer-t ofthe chord increased. with incming Mach number due to compressibiUty effeots while no systematio vaLz1, horizontal *il surface of a Jet- . pqelhd.fightetypa airplane was
4、 tested to determfne its aemdynamic chazaateristics at Mmh numbers in the range of 0.20 and 0.70. The results of force testa and hingeammnt measurements were presented in reference 1. !This report presents the results of chordwise and spanwise pressure-dfetribution measuremente. ! I Provided by IHSN
5、ot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2 NACA RBI No. LpO8 In the application of wind-tunnel. data obtained with solid modela of exaqt profile contour to the calculation of aerodynamid loads on a full-scale airplane wing or tai1,it ie diffioult to allaw for
6、 the effects of surr“aue tilatortion. Because surfaoe distortion ordinarily inoreases with incrb elevator angles of .-17O, -13O, “go, -Go, -ko, -2O, Oo, 2O, bo, 6O, and go; and Mach nlmbers of 0.23, 0.30, 0.40, 0.50, 0.55, 0.60, 0.65, and 0.68. combination .of- these variables. wa.8 l.3.mtted by the
7、 maximum allowable load on eitlier the atabilfzer, elevator, or tail surface as a unit, the allowable load being taken a6 three-fourths of the design limit load. The average dynamio pressuree and avemge Reynold8 ambers comeeponding to the test Mach numbers are shown in figure. 6. The Repol (See Pigs
8、.- 7 to 9,) The dashed parte of the Pa curves. represeqt pressures .which ohange verg rapia_ls due to movemnt 02 the stagnationpoint or elevator protrusions, and for .which appreci.able error in detel-mining the slopes is possible. The chordvise dlstrLhution of the -rate of change of pressure. coe.f
9、ficient with elevator angle at the LbTnch, 47, -%inch, , *Be Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-6 EACA Rp4 no. 708 and 81-mh stations for Maoh numbers of 0.20, O.hU, and 0.60 is shown in figure ll. This figare shows a decrease in Ps with
10、 increasing Mach number over the leading 15 3ercen-k of tail surface and an inorease at 70 and 77 peroent of the chord, The decrease of Pg at the leading cdge with increasing Mach number iB contraq to data obtained from solld models of high torsional rigidity and appears to be caused by twist- or“ t
11、he stabilizer in a direction to decrease the lift due to the center of pressure moving resward as the elevator angle is incsea8ed.i It is ,estimated tkat a decrease of approximately 0.10 of a e+noinent coefficient and elevatol.-balesce pressure coefficient far several combinations of angle of, attac
12、k and elevator -le. An increase in the absolu$e value of either coefficient between M = 0.20 and any other Mack naer has been coneidered positive and a decrea8e3 negative: This figure ehows.that the hinge-moment ooeffioient . increases more than the balance4mnber pressyre coefficient decreales 8 cho
13、rd,. These increases also conkribute to the rise in hfnge-moment, coefficients with Mach number. The combined effects of the pressure ohanges shown in fighres 17 ritloal Mach nusnber of 0,n at CL = 0 and 6 = 0. I HmeveI“, from oonsideration of the effeots of the pealre in the pressure a,ge.ms m howe
14、ver, it is estimated that this oould be increased to 0.80 by eliminating the eurface imgukrities, 2. The rate of change of pressure coefficient with -le of attmk over the leading 60 percent .of the chord increased wtth inoreasing Mach number due to oompreesibility effects, while no systatic vazdatio
15、n wley Field, ?a, . EWERENCES 1. Sahueller, Carl F., Hieser, Gerald, ai Cooper, Xorto and Toll, Th0mP.s A.: Jet“B0Undary Corrections for Reflec tiopFlane Model8 ia Rectangular Wind Tunnele EXCA ARR No. 322, 1943. 3. Thorn, A. : Blookage Corrections in a ClaBed Iligh-Speed Turnel. R. & M. No. 2033, B
16、rriCish A.R.C., 19?.3. I 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. NACA RM No. 108 9 45 50 55 60 65 70 75 80 85 90 95 100 Percent 9 1 0 ,788 ,964 124 5 4.9603 4,8387 4.6341 4.347 I L I I Provided by IHSNot for ResaleNo reproduction or netwo
17、rking permitted without license from IHS-,-,-. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-C. t f “- /C “ . .- a “ “ .- 4 “ “ - “ - _“. 4 cc “ c= 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
18、R I w Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. . . . . . . . . . . Provided by IHSNot for ResaleNo reproduction or networking permitted witho
19、ut license from IHS-,-,-NACA RM No. L7DO8 Fig. 6 I I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Fig. 7 NACA RM No. L7DO8 I I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM NO. L7DO8 i Fi
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21、ed without license from IHS-,-,-Fig. 10b NACA R,M No. L7D08 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM No. L7D38 Fig. 10c Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by IHSNo
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23、ense from IHS-,-,-NACA RM No, L7DO8 c . Fig. 12 I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Fig. 13 NACA RM No. L7DO8 t Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. NACA RM No. L7DO8 Fig. 1
24、4 I t I I I I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Fig. 15 NACA RM No. L7DO8 tcJ 8/-/nch Afton 0 .f .2 .3 .4 .5 .6 .7 .8 .9 LO */, E Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM No. L7D08 Fig. 16 . I I I I I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
