1、NATIONAL ADVISORY COMMITTEEFOR AERONAUTICSg .Zsections _re shown to follow the same trend as the NACA ;6-series sections. The variation of maximum lift coeffcients _ .8with position of minimum pressure for NACA 6-series see- ._tions is shown in figure 18. In most cases these data indicatea small dec
2、rease in maximum lift coefficients of both the _ .4plain and flapped airfoils regardless of thickness ratio as theposition of minimum pressure is moved to the rear. 0 20 #0 0 80 I00 120 140 160f-lop doflect/bn, gl_ degFIC_UI_E16.-Vmiation of maximum section lift coefficient with flap deflection for
3、severalI NACA 6-series airfoil sections equipped with 0.20csplit flaps. R=6.0X10G; reference 16.5j2.0 W_9) I756“ 1.8 _/ js.q)(9 /8I_ 0 ,z_,-_. , _ 13 El ,2b. . .“ .,:d._:- _ .80c - - / Refer-_ .90c- _ _ “_ e_/_x, “-_o_i.o.o_ “ .30 1.00 b A 3.45 40 .=0.18 IDavis (modified) t .30 1.00 b A 3.14 40 No 6
4、. 0 37Lo.18 I66-series (approx.)t .30 1.00 b A 3.34 30 . No 6. 2 37-_=o.18 Ilift position. References from which the data were obtained table I that flaps with the slot lip extended to tile trailingare also given in the table (references 11, 12, and 19 to 37). edge seem to show their highest maximum
5、 lift coefficientsMaximum lift coefficients of airfoils with slotted flaps are at lower flap deflections than with shorter slot-lip extensions.shown to be considerably higher than those of the same air- The effect on maximum lift coefficient of increasing thefoils equipped with plain or split flaps
6、of comparable size. effective chord of the airfoil-flap combination is shown inThe advantage of the higher maximum lift coefficients must figure 27 for various flap combinations on the NACA 23012be balanced, however, against the added complication of airfoil section. The maximum lift coefficients ar
7、e all basedproviding external brackets to hold the flap or of more on the chord of the airfoil with flap completely plicated mechanisms required to operate the flap. Maximum lift coefficients are shown to increase as the totalMaximum lift coefficients are shown in figure 25 plotted chord is increase
8、d either by increasing the flap chord or theagainst flap deflection for the NACA 23012 airfoil section slot-lip extension. Increases in flap size above about 25with various sizes of slotted flaps and in figure 26 for two percent of the airfoil chord are shown to have much smallerNACA 6-series airfoi
9、ls with slotted flaps. These data and effects on maximum lift coefficients than increases in thethe data of table I show that the flap deflections for maxi- lower range of flap size. Increases in slot-lip extension,mum lift coefficients of airfoils with slotted flaps vary over however, seem to be mo
10、re effective as the slot lip is extendeda range of from about 30 to over 60 . Although no rigid toward the trailing edge. Ak_hough the variations of maxi-variation of optimum deflection with flap size or slot-lip mum lift coefficient shown iu figure 27 cannot be expectedextension can be shown, it ma
11、y be seen from the data in to hold strictly for different types of airfoil section, the864781-50-3Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-16 REPORT 938-NATIONAL ADVISORY COMMITTEE FOR AERONAUTICSgao - /oV(5Oq)/.2._.c/C ea Reference c/c ca Ref
12、erenceo 0.10 0.93 II o 0.15 1.00 EL).8 u .256_ .83_ 12 r .2S_1.00 200 .30 .90 21 O _ Q NACA #5-ser/es“ 60x/06 “- _ - - /VACA _6-semles- - - - - _ NACA /4-series- 3.5xI0INACA 230-ser/esJ.4 -0 .02 .04 .06 .0_ .10 .12 .14 .18 .18 .20 .22 .24 .26A/rfo/thickness _af_b, flcFIGURE 44.-_aximum section lift coefficients for several NACA airfoil sections with double slotted and split fl_ps.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
