REG NACA-TN-417-1932 Wind-tunnel tests of a Hall high-life wing.pdf

1、L wNATIONALTECHNICAL NOTESADVISORY COMMITTEE FORNo, 417171ND- TZJXNXL TXST?S OF A HALL ZIGH-LIFT WIKG By I?red E. Weick and Robert SandersLaugley Kemorial Aeronautical LaboratoryWashingt OZLMay, 1932.s. . . . . . .t,1-.;,Provided by IHSNot for ResaleNo reproduction or networking permitted without li

2、cense from IHS-,-,-NATIONAL ADVISORY C6MMITTEETEC?HNIOAL NOTE NO.WIND- TUNITEL !l?ESTS03A HALLFOR AERONAUTICS417HIGH-LIIT WING .By Fred E. l?eick and Ro3ert SandersSUMUA.RY.Wind-tunnel tests have leen made to find the. lift,drag, and center-of-pressure characteristics of a Hallhigh-lift wing model.

3、The Hall wing is essentially asplit-flap airfoil with qn internal air passage. Air en-ters the passage through an opening in the lower surfacesomewhat back of and parallel to the leading edge, andflows out through an opening made by deflecting the rearportion of the under surface downward as a flap.

4、 For or-dinary flight conditions the front opening and the rearflap can be closed, providing in effect a conventional air-foil (the Clark Y in this case). The tests were made withvarious flap settings and with the entrance to the passageboth open and closed. The highest lift coefficient found,CL = 2

5、.08, was obtained with the passage closed.-JINTRODUCTIONEandolph F. EallandThe present Hall high-lift wing is tlhe result of a de- -.”:1velopment which started with a study Theodore P. Hall ofthe possibilities of converting the upper and lower sur-faces of the conventional wing into separate airfoil

6、s, form-ing in effect a biplane combination with a small gap. (Ref-erence 1.) The development was continued with the cogstruc-tion of an airplane incorporating the w3.ng shown in Figure 1, cr.+.:which “was entered in the Guggenheim safety competition.(Refereace 2.) The flaps on this airplane were la

7、ter made automatic in operation. More recently, further wind-tunAG- ?- “-.-tests have been made on a small model of the Hall wing !in its latest form (similar to that in fig. 2). In %oth the wind-tunnel and flight tests substantially higher lift icoefficients were obtained with the high-lift arrange

8、ments -,than with conventional wings, but the approximate nature ofthe flight tests and the low scale of the wind-tunnel testsmade further experiments desirable.“Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-.2.,. :a71a13 a15 a15 -.”t*,:”,“ , - .,“

9、if*Acl”AiTechAieal Note Nog 417 “-.“:-”. .-The present tests hivb-%een made as part of a serieson various high-lift d atidthe en-trance to the ,iaternal passage both open and closed.APPARATUS AND METHODS ,Thq %11 wirig model, which was constructed of lamina-ted mahogany (figs, ? aid 3) had a chord o

10、f 10 inches anda span of 60 inches; . Narrow ribs in the internal passagewere spaced about 3 inches apbrt, .Inthe c,enter of thewing a 4-inch cell.was made solid. for mounting. The. rearflap was supported on hinges ahead of its leading edge.Thus when deflected there was a gap between the flap andthe

11、 lower eurface of the wing, which is not the case withthe wing on the Cunningham-Hall airplane. (Fig. 1.) Inthe model the flaps were hinged at eight points a.long,thespan and provided with small quadrants having holes drilled10o apart for deflections from 0 to” 50- For one test theslope of the upper

12、 surface of the passage just above thefront portion of the flap was increased from 26 to 45. bymeans of Plae”ticinec (Shown in fig. 3 and in an Insert offig. 2.) The front entrance to the passage was closed bymeaqs of a cover plate, making the wing in effect a conven-tional airfoil with a split flap

13、. The cover plate was usedon the model to replace a forward vane or valve; with theplate removed the inside form of the passage simulated thatwith t-evane displaced 30 upward. .-,The 7 by, 10”foot wind tunnel ie of the open-jet typeand 3s described in detail together with the balances andstandard te

14、st procedure in reference 3. The” Eall wing mod-el, which lticked rigidity because of its hollow construction,was suported by a fine wire at each wing tip in addition to “the usual center support. The test-s were made at an ai,rspeed of.8,0uiles per hour, corresponding ta a Reynolds Num-tier of :609

15、,000. ,., ,:, ,-.- .:., .RESULTS AND,DISCWSION - .,., !, ,. .- ,. .,“. .“.Tb.ealusof CL: , “hnd .c.p. areplotted againstangle of attck for the various flap settings. with the pas-sage open in Figure 4 and with the passage closed in Figure9,Provided by IHSNot for ResaleNo reproduction or networking p

16、ermitted without license from IHS-,-,-r.a71 N.A, Technical “Note Mo”. 417imately true for any hngleof atta”ckshove” O“whether thepassage through the wing was open or closed.,“ CONCLUSIONS1. The htghest lift coefficient obtained,with themodal of the Hali high-lift wing tested was of the order ofthat

17、obtained with a conventional trailing-edge flap,2. Slightly htgher values. of the maximum lift coef-ficient were obtained with the passage through the wingclosed than tiith it open.,Langley Me?orial Aeronautical Laboratory,National Advisory Committee for Aeronautics, .-Langley Field, Pa., March 31,

18、1932. .REIWRENCES .“,1. Hall , Theodore- P.: Hall Convertible Airf%il. Thesis. *:Massachusetts Institute of Technology (Cambridge),1928. .,y :”,;+ “+“ 20IiEiEQ 40”Ioz; 60 ( IhaPI 2.0. +/ ,I Ii I I 1.6 I I It!It1.41t t1.“a3t!?1*o.0,0,0,-1- !. ! . I ;qYJ-.- with passageclosed and flap at various qngle

19、s uncorrected for tunnel-walleffec -Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N.A.C*A. Technical Note No.417 3?ig.6Passage open A -Passage closed2.60 .!.2.40 f.2.20i2.00C%adII.8 /i /1.80 :/L/ -1- 1/ I1.60 . a. - - -1.4Q -t IJ i“rI Ij1.20 * L-.1.000 10 20 30 40 w! 60Flap angle,degrees,/+(JFi .6 Variation of maximum lift coefficient with flap aagl -YProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-