1、P RESEARCH MEMORANDUM PRESSURE DISTRIBUTION AT MACH NUMBERS UP TO 0.90 ON A CAMBERED AND TWISTED WING HAVING 40 OF SWEEPBACK AND AN ASPECT RATIO OF 10, INCLUDING THE EFFECTS OF FENCES By Frederick W. Boltz and Harry H. Shibata Ames Aeronautical Laboratory Moffett Field, Calif. * I Cl A.SSfFt3ATIQN C
2、ANCELED Atiiiirr;l.3-li-Y_7-. C;b-yC1-C#kA - . . - .-. .“_“ “ “ “ . I I ay.l-Q;blbltsdQI. NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS WASHINGTON March 9,1953 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-1L .NACA RM A52EO PRESSURE DISTRIBUTION AT M
3、ACH NUMBERS UP TO 0.90 ON A CAMB?ZRED AND TWISIXD .WlX HAVING 4-0 OF SWEEPBACK AM) AN ASPECT RATIO OF 10, INCLUDING THE EFPECTS OF FENCES By Frederick W; Boltz and Harry E. Shibata SUMMARY Pressure-distribution meaaurements were made on a semispan model-of a cambered and twisted wing, alone and in c
4、ombination with a fuselage. The wing had 40 of sweepback, an aspect ratio of 10, a taper ratio of 0.4, and 5“ of washout at the tip. The wing thickness distribution in sections normal to the reference sweep line was the NACA 4-digit root to ll-percent chord at the tip. The wing sections were deed fo
5、r a design lift coefficient of 0.40. CI series and the maximurn thickness varied from 14-percent chord at the The chordwise distributions of pressure coefficient at nine semi- “. epan stations on the wing are presented for Mach numbers of 0.165 and 0.25 ata Reynolds nmiber of 8,000,000 and for Mach
6、numbers from 0.25 to 0.9 at a Reynolds number of 2,000,000. Tabulated pressure data are presented-for the wing without fences and with a four-fence configuration. The results indicate that, at all Mach nunibers, flow separation originated at the tratling edge near-the midsemispan of the wing. The se
7、paration spread toward both the root and the tip with increase in angle of attack, complete flow separation eventually occurring at the outer. sections. Increasing the Reynolds number at low speed reduced the amount of flow separation over the wing. - Upper-surface fences reduced the trailing-edge f
8、low separation out- board of the fences. At the higher Mach numbers, the four-fence configu- ration was considerably more effective than the three-fence configuration. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2 - NACA RM 5220 The spanwise dist
9、ribution of load was found to be accurately predicted by the modified FalkneF 19 x 1 method, provided little flow separation existed on the wing. INTRODUCTION A semispan model-of a high-aspect-ratio swept wing in conibimtion . with a fuselage of high fineness ratio has been tested in the Ames 12-foo
10、t pressure wind tunnel. The wing waq cambered and twisted, had 40 of sweepback, and an aspect ratio of 10. The results -of meas- urements of the forces and moments on the wing alone, on the fuselage alone, and on the wing-fuselage combination have been presented in reference 1. The results of pressu
11、re-distribution measurements at nine semispan statfons of the wing, alone and in the presence of the fuee- lage, are presented in the present report Pfessu?e dafi are also included for the wing with three upper-surface fences -and with four upper-surface fences. NOTATION mean-line designation, fract
12、ion of chord over whfch design load is uniform wing semispan perpendicular to the plane of eymmetry, feet pitching-moment coefficient about the quarter point of the wing mean aerodynamic chord (p“tc:g moment) (See fig. l(a).) local chord parallel to plane of symmetry, feet local chord perpendicular
13、to the reference sweep line, feet mean aerodynamic .chord “ r “ “ . n “ . “ . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM A52K20 3 Cav average chord (e), feet cz section lift coefficient C 21 design section lift coefficient % section pitc
14、hing-moment coefficient IC, (0.25-c .p . ) f Cn section normal-force coefficient c.p. sectfon center-of-pressure location, fraction of local chord M Mach number P pressure coefficient p2 local static presswe, pounds per square foot P free-stream static pressure, pounds per square foot 17 free-stream
15、 dynamic pressure, pounds per square foot R Reynolds number based on the mean aerodynamic chord I S area of semispan wing, square feet t maximum thickness of section, feet Y lateral dietance from the plane of symmetry, feet a angle of attack of the root chord at the plane of symmetry, degrees a, ang
16、le ofattack uncorrected for tunnel-wall interference and angle-of-attack countercorrection, degrees cp angle of twist measured in plase parallel to the plane of symmetry (positive for washin), degrees 1 fraction of semispan Provided by IHSNot for ResaleNo reproduction or networking permitted without
17、 license from IHS-,-,-4 MODEL AND APPARATUS The wing had 40 of. sweepback, an -aspect ratio of lo, and a taper ratio of 0.4. (See fig. 1(a) .) The reference meep line was the line joining the quarter-chord. points- of the sectfollg -inclined hOa to the plane of symmetry (26.65-percent-chord pointe o
18、f the streamwise see- tions) The thicIniesses of sections perpendic-ular to the reference sweep line varied from 14 percent-of the chord.at.the root to 11 per9ent of . the chord at the tip. The tip ms- washed out 5“. The twi Reynolds number of 2,000,000, although at the higher Mach numbers the reduc
19、tions in : - section normal-force-curve slope occurred at considerably l6wer angles of attack over the outer half of the semispan. The effects of Mach nu- ber on the section normal-force coefficients far the wing-fuselage corn- - . bination are summarized in figure x. An inspection of the section pi
20、tching-moment data in figures 11 . through 17 reveals that, at the higher section normal-force coefficients, . a rearward movement of the centers of pressure-occurred at most sections. The effects of these section center-of-pressure changes are not evident in the total pitching-moment curves md, her
21、efore, it appears that the longitudinal stability of the wing was primarily governed by changes in the spanwise distribution of normal force. Effect of fences.- The effect of the four fences on the character- istics of the wing alone at a Mach number of 0.165 and a Reynolds number of 8,000,000 (fig.
22、 11) was ta re-duce the loeses 3n the section normal- force-curve slopes and the changes in the section centers of pressure at most sections. The net result of these changes was an increase of about 16 percent in the-maximm lift coefficient of the.wing, a delay in the abrupt increase indrag to appro
23、ximately the maximum lift coefficient, and an elimination of practically all of the longitudinal instability of the wing at the higher lift coefficients. . . 1 Similar effects of fences were obtained for the wlng-fuselage combination at a Mach number of 0.25 and a RepOlds number of 8,000,000 I - Pro
24、vided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-10 MACA RM 5210 . . (fig. 12) . The dam ,indicate substantially he same- improvement in the 1. section characteristi- for either the three- or thefour-fence config- uration. At a Reynolds numberof2,000,000
25、 (fig. 13), the effect of the -. fences on-the section characteristics was more pronounced than at a Reynolds number of 8,000,000 since more extensive flow separation existed at the lower Reynolds number (cf. figs. 7 and 8). - “ . . .!j - - In figure 14, it is shown that at a Mach number of 0.60 the
26、 improve- ment in the section characteristics due to fences was considerably lees - . - than at a Mach number of 0.25, the effectiveness of the four fences 1sav- ing been slightly greents in the lift, drag, and pitcking-moment characteristic. . -I . .“ .“ . . . - - -. The use of upper.-surface feiic
27、es was found to be effective in producing significant increases in lift oyer the outer portions of the wing by reducing the amount .of separation .outboird-of kach of the fences “ and thereby causing substantial improvements in the lift, drag, and pitching-moment characteristics. At the higher Mach
28、numbers, a four- fence configuration having extended fences was considerably more effec- tive than a three-fence conffguration of small felcee. . . . - . . “ L - - “_ - - “ . “ . . f . . “ - . c . “ The modified Falher 19 x lmethod wag found to predict the spaswise load distribution to a gooa degree
29、 of accuracy pgorldeg little flow sepa- ration existed on the wing. .“ - Ames Aeromutical Laboratory . .“ National Advisory Committee for Aeronaut3-cs - . - “. MDffett Field, Calif. - REFERENCES t .“ . 1. Edwards, George G., Tinling, Bruce E., and Ackerman, Arthur C.: - “ The Longitudinal Characteri
30、stics at Mach Nlber8 up to 0.92 of a Cambered arid. Twisted Wing Having bo of Sweepback and an Aspect Ratio of 10. NPLCA RM 5218, 1952. . .“ . -.“ 2. Loftin, Laurence- K., Jr.: Theoretical and Experimental Data for a Number bf NACA R, 8,000,000 - Concluded (b) w, loo, U0, 14O, 16O, 18O, 20 - Conclud
31、ed 7 at- 160 4.25 33 -56 .m .u -35 .30 .w .a .l6 .OB -03 - - “ “ “ - “- “13 “ .55 3s .a .43 .34 .a .a -13 .I? -01 .m “ - 180 -0.60 .47 .53 .% .a .39 -32 .4 - 19 .l4 - .03 R, 8,000,000 (a)%, -2O, o*, 2O, 4O,. 6*, 8O . .“ - Per- osnt ebotd - 0 4.0 1.5 lO.0 7.0 20.0 15.0 30.0 sO.0 40.0 60.0 70.0 80.0 9
32、0.0 93.0 0 4 .O 1.5 10.0 7.0 20.0 15.0 40.0 3.00 60.0 50.0 70.0 90.0 80.0 53 .O 7 “ -7- - “- -“ “- “- -“ “ - “- 4.33 -. 31 -.2b -.P :E -.03 .06 - “- “- “- “- -“ “- “- “- -.31 -.a 41 -. 18 -. K -.OB .06 - 7 4.56 -3 -.Lo -. 53 -.3 -. 17 -.24 -. 12 -06 -.m .06 .m -. 57 -.s3 -.43 “31 -. 37 -.23 “ “_ -“
33、 -“ -“ -“ -.16 -.m .01 .e7 I .07 “_ - 0.n -.38 -. 49 -. %? -. 55 -n -. )o -. % -. 43 -. 33 -29 -.25 -. 16 -. 03 .cn -59 .90 -.a -. 59 -.57 -60 -. 49 -. 48 - 45 -. 3) -.28 -.23 -. 15 -.a? .as -. 50 .e -.I-; -.In “- _“ -.a “_ “- .10 .10 “_ “- -“ “- .Lo 20 .17 .28 .06 .13 .C9 -17 .06 .ll .OB .12 -.SS
34、 P -.25 -21 -. 14 -01 .06 -.el .53 -. b4 -.b -. 32 -. 35 -.35 -. 30 -.21 -55 -. 19 -.03 .04 - :% -. 37 -29 -.a3 -. 15 -.01 , .Qs .uI -.63 -39 -. 61 -. R, 8,000,000 - Continued (a)%, -2O, oO, 2*, 4O, 6O, 0O - Concluded l- P“ cent sama - 0 1.5 4.0 7.0 10.0 15.0 20.0 30.0 40.0 90.0 60.0 70.0 80.0 95.
35、0 90.0 “iaee - attA.cs 40 -.61 0.56 “64 -. 6e -.a -. % -.go -ab4 -. 41 -39 -23 “29 “16 -.4 .06 - t 7 80 a.54 -1.79 -1- 37 -1.21 4.10 -. 94 -81. “% -. 4 -. 36 -. 47 -.e8 -. 17 ,u? .04 - 00 - “- “- “- “- “- “- “_ “_ 14 -. 20 -23 -.l6 112 -.a? .a) - 60 4.16 0.10 “97 -. 91 -85 -. n -. 66 -. 49 -. % -. 9
36、1 -. 33 -. 17 -. 26 “03 .a) - se “- “- “- -.% -. 5e -. 33 -.a -.I7 -. 11 0 “- -m -07 .w - L “_ “- “- “- -. 33 -. 4 “3 -. 16 -.lo -.os .a .a5 .08 .la “- - 50 OSl .* .a .ll .06 .10 -4 .4 .ll -10 .lo .w “- “- “- t “ - 0.q -. 4 -. 12 -. 14 -. 10 -. 09 -01 -. a) .08 .05 .u) .ca “- -“ -. $0 -. 38 “35 -.4
37、32 -24 -.a “14 -.03 .cr5 0.56 b/2 0 1.5 4.0 7.0 10.0 15.0 M.0 2% %LO 60.0 70.0 5QO 80.0 95.0 0 1.5 4.0 10.0 7.0 20.0 W.0 40.0 30.0 50.0 60.0 70.0 80.0 90.0 59.0 0 1-5 4.0 10.0 7.0 20.0. 15.0 30.0 50.0 Lo.0 70.00 60.0 80.0 90.0 55.0 - - - “_ “_ -“ “_ -“ -“ “_. - 14 -. 14 -. 9 -. 12 -. ll -. 08 .a .a
38、) - “- “- “- “- -“ -“ -“. “- -12 -.ll -. ll -. 10 -.w .m .06 - “- -“ “- “ - “- “ - “- “- -05 -.ll -09 -. 10 -.w .a3 .w - “_ “- “- “- “- “ - “- 122 -23 -. 21 -18 - 14 -.lo 0 .a) - “- “- “- “- “- “- “ “- -. l9 -18 -W - 13 -. 09 0 .t% - - “- “- “- “- “ - -I - “- “ - -. 14 -.u -. 13 -.a7 -.u .ce .4 - “-
39、 -29 -.03 -. P -. n - 35 -.36 -.3b -5 30 -2T -22 -,a -. 13 -.a .9 -56 0 -.l8 -.a -3 - -. 31 -. 30 -. 28 -.2? -20 “24 sl8 -.le - “. 01 -9 -40 -15 -. 05 -. 14 -.Is -. 19 -.20 -16 “21. -20 -.a - -. 13 -08 .01 .a5 - - - “- -. 44 -.e -3 -.ST -. 4s -39 -33 -.a -.a -. 15 -.01 .a) 33 -. 43 -.XI -. ?Q -. 51
40、 93 -. 4s -. 37 -. 31 “33 -25 -.a, -. 14 -. ce .w .% -39 -. 3s -. 9 -9 -35 -.P -a? -.w -25 -.20 -. 15 -10 .a .06 :E - - - -“ -.w -1.00 -.w -.El “70 -. 66 -. h -. 40 -.a -16 -.24 -.ce -9 93 .I? -.e -73 -66 “0 -. 43 -48 - 37 “32 -24 -15 -.03 -03 -62 .46 566 -.67 -. 37 - 51 -4s -31 - 34 -. Pg -24 -.1
41、9 -. le 0- -05 -.n - -.m - - “- -1.60 6.37 12.17 12.06 -.%? “69 -55 -.m “3 - Y ,e6 “la -01 .QY -1. b - h 12.20 -1.m -9s -. E3 -73 -59 -31 z:9 -. 26 -18 -ce .os .w 4- 15 4.03 -. 63 -78 -67 -. s8 -. 43 - 34 -40 -27 -20 -. 12 0 .a) - - “- “- “- -“ :B -. 3s -24 - 17 -.a1 -.m .os .4 .w “- - “- “- “- “- “
42、 -. 47 -. 37 -.27 -.I2 -.ob -. 01 -03 -4 -09 “- - “_ “- “- - “- -. 50 -. 38 1 17 -26 -.09 . 01 .a) .4 .lo “- - “- -.03 5u . I4 -. 14 -.OB -.ll -. w .a? .4 .a .a3 .w “- “ - - “- -. 13 -.20 -.a -.la -. 13 -.lV -. 03 .a .05 .ob .OB .10 “ - - “- “38 -2.5 -Q9 -22 -. 17 sl2 -.w -. 03 .ob .03 .w -10 “- “
43、 “- .30 .le .) -.6 -.16 I: E -28 -. 14 -.03 -.01 - -“ .53 .55 .s .29 .25 .I9 .17 .16 .15 .lo .E “- “- “- - -“ .% .x .38 .30 .26 .a0 .17 -15 .15 .la .XI .55 .x .39 .P .26 .20 .l6 .l6 .I5 .16 .ll .03 “- -“ “- - - “- “- - 3-90 4.20 -6. %, 0.165; R, 8,000,odo - Concluded (b)%, loo, 12O, Uo, 16O, 18OY 2
44、0 - Concluded i - Pa- eent chard T I mse BtAUon 0.36 b/2 0.68 b12 0.83 b/2 0.94 b/2 - le -2.53 4.39 -Le -l.% A.14 -1.3 “95 -. 76 -. 62 -. 51 -. 39 -39 -. 17 “102 - 03 - - - 4-32 d.a? 4. z -LC3 -1.33 -.sa -.m -. 63 -. 50 -. 37 -. 15 -27 0 .04 - 200 -5.83 -8. R 3.23 -4.m 4.N -2.a -1.37 -l. IO -. 87 -.
45、 m -. 47 -58 -. 35 -. 10 “eo - lo0 0.51 -“ .% .39 .w 27 .2u .la .l6 .u .14 .u .og -“ “- T 0 1.5 4.0 10.0 20.0 15.0 30.0 40.0 m. 0 50.0 70.0 80.0 90- 0 53.0 0 1.5 7.0 4.0 lO.0 15.0 20.0 7.a - E: 50.0 60.0 70.0 80.0 9.0 53.0 3.83 A. 18 -2.59 4.2b -1.09 4.- 4.24 -. 93 -. 74 -. % -. 4.4 -. 31 “la -. 06
46、a? - “- 3.a -2.81 -222 -1. ea 4.53 4.9 -99 -.74 -. 56 -33 -.25 -.lo -. OL 0 -“ 0.03 “_ .s .33 .45 .bo .P -27 .24 -21 .18 .lo -13 -“ 4.33 -l.ol -. 32 -22 -. cg -. 10 T “- A. 74 -3- 34 -2.60 -2.16 4.73 4.45 a. a7 “78 755 -. 36 -. 19 I:% -. (* “- 3.63 -3.= -2.w -e. 51 23 -1.12 -. 78 -. 51 -. 31 -. 17
47、 -. l2 “14 - 15 “- -5.51 A. n “21 -2.a -2.00 a. 10 a.60 -.P -. 33 -. 45 -.28 -. 29 “26 -. 19 “- .x . 55 -39 -31 .26 .21 .I? -15 .Ij .14 .n .og - -“ “- .3s .57 -47 .38 .E7 .33 -22 .17 .16 .15 .l2 .w “_ “- -“ .OB .% .53 .e -50 .P .27 .21 . 6 .la .u .a “- “- 0 1.5 5.0 10.0 7.0 -1.40 4. P -1.63 4. 54 -1
48、2k 4.06 “so -. 58 “70 -48 -5 37 527. -.l6 -.a? .04 -2.60 -3.02 -2.lo 4.74 -a*% 4.m 425 -. 65 -. m -. %? “ 39 -28 -. 14 -02 -01 -4.04 3.16 4-59 4.09 4.78 4. e 4.m. -. es 7.55 -. 71 -. 40 -. 13 “27 -. 03 -. 01 3.71 2.64 3.09- 4. 47 4.w 4-64 4. 34 -.se -. 76 -57 -.Lo -. 13 -23 -07 -06 A.28. ?.do -2.n
49、2.13 4.73 4.35 4.u -.7a -. 46 “61 “33 -. 20 -.w -.e -.03 - - -7. 47 3.49 -3.57 -2-73 -2.29 am 4. 4.3 -.m -. s7 “26 -40 -bl3 -. 17 - 12 3.86 4.35 -3.m -2. c -l.* 4.6 -. 83 -. 3 -. 46 -. P -.20 -. 12 -.a -.a8 4.23 - -9.33 -4.00 4.9 -3.03 -2. b7 4.91 4.9 4.05 -. 79 -. z -. b5 -28 -. 35 -.23 “20 -7.57 3.05 3.a -2.69 -2.n 4.32 -L R, 8,000,000 (a)%, -2O, Oo, 2O, 4O, 6O, 0O . 7 5 “ R,
