NASA NACA-RM-A8F15-1948 Investigation of a thin wing of aspect ratio 4 in the Ames 12-foot pressure wind tunnel II - the effect of constant-chord leading-and trailing-edge flaps on比.pdf

1、copy No. 6 RM No. A8F15 INVESTIGATION OF A THIN WING OF ASPECT RATIO 4 IN THE AMES 12”FOOT PRESSURE WIND TUNNEL. II - THE EFFECT OF CONSTANT-CHORD LEADING- AND TRAILING-EDGE FLAPS ON THE LOW-SPEED CHARACTERISTICS OF THE WING By Ben. H. Johnson, Jr., and Angelo Bandettini Ames Aeronautical Laboratory

2、 Moffett Field, Calif. NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS - Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. . l 3 1176 01331 5511 -F-; - UNCLESIFIED NACA RM I?o. A leading edge at _ ._ -. - small angles of attack Accc%diugly, a%lliarp lift

3、-producing devices are essential to provide the aircraft with acceptable lamding.and tatiff characteristics. In order to ascertain the effectiveness of constant-chord lead- and trailiwdge flaps applied to such a uing, tests of a semispan model have been conducted in the Ames Moot pressure wind tunne

4、l. !l?he model represented a wing of aspect ratio 4, a taper ratio of 0.50, with a sharp-edge diamond profile of thickness ratio 0.045. The tests were made at Mach nunibers of 0.20 and 0.30 and at a range of Reynolds numbers from 3,000,000 to 10,000,OQO. CL CD cnl sYME3oIs The following symbols are

5、used fn this report: lift coefficient drag coeffisient pitching-momsrp leading edge as evidenced by. the higher lift coefficients at which the center of lift on the wing moved rearwsrd. 3. 5zllaximum Uft-drag ratio was improved 17.7 percent over the value of 34.1 for the plain wing by deflection of

6、the leading- edge flap. Deflection of either of the trailing-edge flaps for the range of flap angles tested reduced the maxirm,m lift-drag ratio but improved the lift-drag ratio at the higher lift coefficients. The lift-drag ratios at high lift coefficients were greater with the trailge plain flap t

7、han with the trailing-edge split flap. 4. For the combinations of flap deflections tested, modification of the wing profile by rounding the ridges practically eliminated a soall scale effect evident in the pitchimment data at the higher lift coefficients. Variation of the Reynolds , lo) 0 Vsa, 9 VsC

8、m Figure 5, The effect d the. le M, 6.30. , 1 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-22 RACA RM IVo. A8Fl5 .8 .6 unless otherwise noted. -2 -4 -.8 0 .04 .08 .I? .I6 20 24 28 .32 I I I 1 1 D?vg coefftimf, c, IAI,0.30, Provided by IHSNot for R

9、esaleNo reproduction or networking permitted without license from IHS-,-,-24 . . .8 I I I I I I I I I I II 61 I I . . c P . I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-8 -4 0 4 8 I2 16 .04 0 -.04 -D8 -.12 -46 -20 -24 Angkq of attack, a, degrees tim AI, 0.30 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-