NACA RM L6L27a - Propeller Shanks

Copy No.

RM No. L6L27aSS44STRICTED CANC

NACA

RESEARCH MEMORANDUM

AERODYNAMIC CHARACTERISTICS AT HIGH SPEEDS

OF FULL-SCALE PROPELLERS HAVING

DIFFERENT SHANK DESIGNS

By Julian D. Maynard

Langley Memorial Aeronautical LaboratoryLangley Field, Va.

CL.ASSIRCA-1 iON CANCELL''

Authority

r., Aeron. Rte ea the National Cefense t the United^^ Ithln the m.=of the Eaplon U Act,

USC 59:31 and 32. Its transmission or therevelation of Its contents in any manner to an—1horized person Is prohibited by law.Information an chassified may be Imparted

only to persons 1n the military andthe ^Nted States ,

cfvt^en^o ceBl'rs end'lyd@1so215Government who have a legitimate interestthereinand to United States citizens of (mownloyalty and discretion who of necessity must betigef lu !!Il tie! (a i

NATIONALFOR

ADVISORY COMMT "THIUM66 to

AERONAUTICS the filar of the Ndtion^

WASHINGTONAdvisory Committee

February 13, 1947 for AeronauticsWashington, D. C,

CLASS-5TP1CTEL CANCELLB"

NACA PM No. L6L27a CLAURCkTini CANCELLBNATIOVAL AD`IISORY COIdMITTEE FOR AERONAUTICS

R1= SEARCH MLMORANDUM

AERO:YNAMIC CHARACTERISTICS AT HIGH SPL.EDS

OF FU LL-SCALL- PROPL-r LF.RS HAVING

DIFFEREVT SHANK DESIGNS

By Julian D. Maynard

SUMMARY

Tests of two 10-foot-diameter two-blade propellers'Which differed only in shank des!.gn have been made in theLangley 16-foot high-speed tunn el^ T`ze propellers aredesignated by their blade design numbers, NACA 10-(5)(08) -03,which had aerodynamically efficient airfoil shank sections,and NACA 1()-(5)(08)-03R. which had thick cylindrical shanksections typical of con-ventional blades. The propellerswere tested on a 2000-horsepoTer dynamometer through arange of blade angles from 20 0 to 55 0 at various rota-tional speeds and at airspeeds up to 496 miles per hour.The resultant tip speeds obtained simulate actual flightconditions- and the vahiation of air-stream Mach numberwith advance ratio is -ithin the range of full-scaleconstant-speed propeller operation.

Bcth propellers were very efficient, the maximumenvelope efficiency being approximately 0.95 for theNACA 10 - (5)( 08 ) - 03 propeller and about 5 percent less forthe NACA 10--(5)(03)-03R propeller. Based on constant-power and r•oteti oval speed, the efficiency of theNACA 10-(5)(08)-03 propeller was from 2.8 to 12 percenthigher than that of the NACA 10-(5)(08)-03R propellerover a range of airspeeds from 225 to 45C miles per hour.The loss in maxim-o-m efficiency at the design blade anglefor the NACA 10-(5)(08;-03 and 10-(5)(08)-03R propellerswas about 22 and 25 percent, respectively, for anincrease in helical tip Mach number from 0.70 to 1.14.

CLAURGATION CANCELLIEr,

Ypp

2

NACA RM Yo. L6L27a

The high drag of the thick inrer suctions of theNACIA 1C-(5) (08) -03R pz•opel.lar was the chief source ofefficiency loss, especially at hi-7h values of advanceratio corresponding; to high forward speeds.

14Th0DUCTI0N

The NACA has designed and constructed a series cffull-scale 10-foot-diam:;ter propeller blades to be usedin an extensive research program for the purpose ofimproving tha high-spend efficiency of propellers. Theprogram includes investigations to determine the affectof

Blade-shank design

Blade-secti on camber (or design 11-ft c(-efficient)

Prcpellar solidity

Thickness ratio of the blade sections

Different blade s3ct 1,-ns (Clark-Y and F[ACA 16-series)

This program was first delayed by dif-L'iculties in thedesign and construction of a suitable dynamometer withwhich the full-scale propellers cov.ld be tested at highspeeds. SubsequJntly, special war -tLme pro,i. cts withhigher priority dela " ed the tests, and an emerganeyprogram of tests was begun in the NACh 6 -foot high-speedtunnel,, These tests ware mad.- with model propellers 4feet in diameter, and the results showing the effect ofcomp ressibility, solidity, and canibar are raportad inreferences 1, 2, and 3. Furth.ar tests cf modal pro-pellers made in th,3 B3 -foot high-.speed tunnel (reference4) have shown that tile. higtest nropaliar• efficiency canbe obtained only if the shanks are broad and thin.Hlso, wake-survey measurements made in flight tests ofone of the NACA designed prrpeller•s with round shanks(reference 5) have s-lown the imncr• tanca of improving theshank sections of propellers used on high-spend airplanes.

Tests of th° fall-ccale propellers are now beingmade in the Lanoley 16-frot hi gh-speed tunnel and, becauseof the ur_Tant n.::ed f,-r design information, the data in the

nkC-4 Rm, ? ,i o .u6L27a 3

present paper are presented t^ det^rzmina the effect cfblade-shank design. E. secondary curpc^se ci the pr esentpa^;ar• is to compare values of px°opulsive efficiency asfound in the model tests vrith values of nrcpellerefficiency based cn shaft tension as f ,-uad in the full-scale tests.

Tha characteristics of tw o c.f the NjiCA propellersthat dif fc,red only in shank design are presented firblade an,71es ranging fr-m 20 0 to 550 at various rota-tional speeds and of airspeeds rangirgr frnm 60 to 496miles per hr?fi . The resultant tip speeds cbtained simu-late actual fl. {uht conditir-ns, and the variation of air-stream Mach number with advance, ratio is within the rangeof full-scale constant-speed pror):,ll.er nre-raticn.

R prop;11ar tip radius

r radius a- an y blac;e section

bl.ada anal:. at any radius, de?-,rees

X00 4R blad;; an le at 0.75 radius ., degrees

eL d

tlade - sect'cn design lift coefficient

h blad„ sacti.cn maximum thickness

b hale width, cqcrd

i^ air-strewn Itiac l? numbergri t helical tip Mach number M, ,`f 1 +; r

V cirsbeed, feet rer second

n propeller rotational speed, rps

D propeller diameter, feet

J proD;e1l3r advance ratio (V/nD)

NACA RM No. G6L27a

P mass density rf air, slugs per cubic foot

T propeller thrust, p^unds

4)C T thrust c ^ef'1 icient IT; pn2D1

P power absorbed by th:, propeller, fort-pounds per second

C P power cr3fficient (1'/pn"zDc)

/I/TI propeller efficiency iJCP,

A L- AFi-il :JS

Pr•r yeller dvnamcm,ter.- r_ 2000-h^rsapower prop-_llardynamoin-ter was used to test the propellers in the Langley16-f"cot high-spJad The dynamomatar is poweredby two 1000•-hors,ncwer electric maters arranged in tandemand coupled fcr the presant tast y to allow the power ofboth motors to ,a exr._nded thr-ugh a single propeller.ja variable-frequent) pcw.;r supply affords an accuratespeed ccntrrl from 1.00 to 2100 rpm with a parris-sibleoversp,^:,,d up to 2280 rpm. The motors are s zpported in ahousing in such a way that their casings are fra: torotat and also free tc rr:ova axially with th 'Ar shafts,The axial and rctatirnal movamants are restrain,d bypneumatic pressurra cansulas, thrust ar?d t^rque beingproportinnal to the pr'-'ssu-a required to restrain themotion. Thrust p?--ensure is indicated as thrust force bymeans of pnaumat c.. scal.<-s and torque nressu?. : e as torqueby means of liquid marinmaters. The d7namomater is cali-brated with the propeller shaft rotating;, and. both thrustand torque maasurem-Ints rive strai ght -line oalibraticnserigur,s 1 ar.d 2 are photo , raphs of the dynamomatar• mountedin the Last suction -f the tunnel, and figure 34 is askatch showing nr•incipal d`mansions of tha dynamometerfairing and spinn r. The shape of th;; spinner and fore-body is desi^-nad to produce uniform axial flow at fraa-stream velocity in tha Plane of the nrrpaller. Pressureorifices are located between tlh- stationary fairing andthe orcpallor spinner to a.ffcrd a correction for anychange in pressure at the spinn:;r-fairing junct l.zra dueto the p_r• opaller operation. The holes in the spinn_er

? ACA RM L^10 . L6 ,27a 5

surface for the r)ro-oel.lcr blada shanks are made verysmall (fiP. 1) but are not scaled. The diameter of.' thepr(, x)e lla r sr innar• is 21.7 percent of the diameter of a10-foot propeller.

Pre ,pell er blades.- The two-blade propellers tastedare designated here-In by their blade desi.Tn numbers,N CA 10 - (6)(08) - 03 and NACA 10-(S)(U')-n The digitsof the blade dosign numbers have the following signifi-canceo Tlie digits in the first jrriiap of n?mibers representthe propeller diameter in feet, the digit in the firstrarenthesis is ten times the basic desigli lift coefficient,the digits in the second narenthesis are the thIcknessratio in percent at the 0.7 radius, and the di.ci t s in thethird FrcuD represent the solidity ner blade at the 0.7radius. The latter R indi..cates a Made with a ccnvan-tional cylindri-cal s'.-,ank. The 1q- ACA 16-series bladesections are ^zsed, and th.^ 'ACA lv^^-(5) (08)-03 prc-r)allor is desi gn:d to obtain vary hi,Th aarodynariicefficiency, all but the most eleman'tary strength consider-ations being disregarded. Efficient airf(, il sectionsextend to the srinn:;r sur.faca for this propeller, whichis :lesiFned to bave t.ho Betz minimum induced-anargy-lossloading (re fer•er_ce 6) when op--rating at a blade angle of450

at t:^e 0.7 radius and an advance ratio of 2.1. ThedesiFn procedu? e used coasists in f india the cpti:munloading ,fri g: nrofil„ drag ass ,--m--d to be zero and thandatermiain=T th;; bast blade shape for that loading when athickness distribution is assum,d. The 'LACA 10-(5)(08)-03Rpropellor r--prasants a structural compromise havingcylindrical shanks typical of conventional prop-lljrs,Ti?:; :'et-- load distributi^n is maintained except forsections nea- the spinn ,3.r surface. Clad---fo rm curves forthe two designb ar-, shown in 'M ura 4, and figures 5 and6 are phctcc*rani~s cif the b-ladas. x comparison of theshank sections at twc radii is shown in figure 7.

TESTa

Thrust, trrcua, and rotational weed wars measuradfoo aac I prop' lar during; tests at blade ane-las of. 20°25_, 30°, 35, 40o , 4`°, 500 , and 550 at the three-quart

er (45-inch) .radius. A constant rotational speed

was used fc^, most of the t;;sts, and Iti. r nE--, o' adv_znccratio (J = n7) was cover: d by clanging the tunnal

6 MACA RM No. L6G27a

airspeed, which could be varied from ab out 60 to 496 milesper hour.. At the higher blade angles the complete rangeof advance ratio could not be covered at the higher rota-tional speeds because of power limitaticns. In er3;;r toobtain propellor characteristics at maxitnum tunnel air-speeds a blade angle (450 ) was chos;;n for which the peakaf.ficiancy operating condition could be attained when thetunnel airspeed was a maximum and the dynamometer wasoperating at its maximum power and rotational speed. Forthese t,,, sts at a blade angle of 45 0 the rotational speedwas varied to obtain data from peak efficiency to thezaro-torque operating condition. The range of bladeangles covered at the various rotational speeds usad inthe tests of tha two prnoallers is given in table I.

R2DUCTION Or DAT1i

Th3 test r:;sults corrected for tunnel-wall inter-farance and. for forces actin '- on the spinner are present-ad in the form of th:, usual thrust and power coefficientsand propeller ^f._flciency. .

Def initicn_cf . -^rcp; 11.r thrust.- Prop--11,: , r thrizst,as usad herein, is de, f'in.,d as` th-- .:haft tension causedby th3 sx)innar-to-tip part of the blad, rotating in theair strJam. The indicated propallar thrust. nus beancorrected by the amount of tila tare thrust found inoperating the dynamora,, tar and spinner without propel.larblades at the. sam3 valu,s of airspa::d as w.;ra used in thepropellor tests. A further corretien was made fcr theinflu:;nce of the pressure fi:;ld of the propalltir actingat thy; juncture betwe3n the spinn.1r and tha stationaryfairing. The chant in spinner thrust due to a change inpressure at the spinner-fair ing juncture vari:.d with pro-pallar operating conditions and was deter.minad frompressure maasuramints in the juncture b:;twaen the pro-paller spinn-r and th fixed fairing; at the rear of thespinner. Values of thrust coefficient w:re changed anaverage of 0.001 by this correction to the spinner thrust.

Correction for wind-tunnel-wall intarfa~:,nce.- Aco.rr :cction has baen arplied to thu tunn-A. datum v . lccityto obtain thj co.r ,Vesponding fr:re-straam airspeed. Thiscorrection Is n,, c-,ssary bi:;caus the flow Fast the pro-paller is eoristrained by the walls of th:; tunnel, and the

NACA R7 Yo. L6 L27a 7

axial valocity which occurs in front of the propellerin t1re vind tunnel differs fr^m that which would occur infree air under the sane operating ccndit ens. Thisequivalent free airspeed >^as teen determined experi-m-antally and. was found to agree; well with values calcu-lated from Glauert's equ•aticn (reference 7) ;ienca, onlytn.e theoretical correction has been. used for the dataobtained in these t:;sts. tilso an i.n,,-estigation has beenmade (reference 8) which indicates tr,at no tunnel-walleffects of significant magnitude exist other than thosefor which Gl:auert's correction is aphlied. The maxirumcor.r.ecti.on for any condit.i.cn of opez, a.tion was ax-proximately7 percent (highest value of t'-irust coefficient for thelowest value cf advanc3 ratio), but for the peak affi-ciwncy conditi_on the correction for wind-tunnel wallinterf ;rence amcunt--d to lass than 2.2 p-.rcent at allvalues of advance ratio nbov-, 0.7 and to less tr^an 1 per-cent at values above 1.2.

^SULTS AN DISCTz;SIO?^T

Faired curves of thrust coefficient, power coaf-fiei.ent, ind prcoall ;r efficienc y plotted againstadvance ratio are pi esentad in fi Tu ..res 8 through. 16 forthe N C nr•cpellar and. in figures 17 through22 for the ^1ti^h propeller. Test pointsare s',,-)wn on the fi g,aras giving thrust and power ceef-flc.i_:nts Tha vartaticn of air-stream ,'Iach number andhalic ,31. tip ".133' nia..be y ,,vith advance ratio is shown onthe .figures i-iving T3rcp.11e:;7 efficiancv.

In ,:re trots cf tree NACA 10-(5) (08)-03 prcr•ellar ata rotational s:a:; i ^f 1140 rpm a bJ --flutter conditionwas en;;euatar:_;d f rr blade angles of 450 and 50 0 . Tiroflutter was detected oy sound and occurred w?-,.n tiia bladeswere operating in a stallad condition as sh r,t ,:n in figure8.

Saverai Tests ti3re repeated dur•i.ng the test programand t'n_: resu)_ts obtaiL agr„ad with the results nre-s--rtad within 1 p r c ;rat. For purpcsas c.i corc.pari son,thzrefcr ;, the 3-ita, ara c^nside.r :d accilr=+te to within 1pare3nt and the fuire:l :, nv:,lcpes are b_11_eved to beaccurate to w -tn' n much cicsar limits.

8 NACA Rid No. L6 G27a

Effeot of shank ^ dasi_rrn on max_mlur. efficier_c^,- Theenvelops curvas f,. prep-, liar -a fficienc5 at the differenttact rotational spuds a].'e svinwn iii figure 23 for treeNACk 10-(5) (0?)-03 and 10-(5) (08)-03F-L prop. allers. Thecurvas snow high efficiencies for noth nrr-pl-1 hers, parti-cularly at a rotational spe:;d of 1350 rpm. At thisrotational. snacd the NAC:i 10-15)(03)-03 prep-ller has ananralop , eft'icienc^r c.f slid;htly mere than 0.95 at anadvance ratio of 2.1. 111 1 1-, :;nvelona efficiency of thecylindrical-shank or• cpaller 10.90) 1s abut 5 perceptlass at the sang- v.Oua of advance rutic and rotationalspeed. This di f f-arenc Is in agr•eerrant with tha resultsrapertad in refer ace 4. tit 21EG rpm and an advanceratio of 1.1 the differ ,inc =a in waxit:ium efficiency cf thetwo proaell ers is abcu.t 6 percent. This comparisonshoz, s tin€t t at the lotArar advance, ratios (corresporiding tolow fc i ward speeds) a large increase in -rotational speedhas on17 a small e.ifact on tflo lose in afficienc-y causedby the inefficient sha:zk sacti.cns of the%iCA 10-(5) (08)-03k pr.^n^ll.:r.. Thls was also shownin the flit-ht t:,^sts re ^tapo3d in ra r•feanca 5.

Alt},eugh then, is some difference in the thrustcoeffici.cnts at maximum :,e fficiency for the two pro-pa1.1-, rs, tri g lower ef.ficienc;^r of tr.e hCti 10-(5) (08)-G3Rpropeller is dui princ z p ally to the hiqizar mower ccuf-fic i antc at maximum efficiency. r comparison of thepo^aar -coeff ici . nt curves in figure 18(b) with thos.D infi.g;ura 9(b) shows that the values of n-,war co„fficientfor max .mum efficiency are hLE_har for the propeller withcvlind.r• cal shanks than "or the propallar with efficientairfoil shanks, and the diffarance inc.r,;ases with in-creasing values of advance ratio. (Sirr.ilar results wererapr, rted in refa~'ance 4.) Since both propallirs w:;redesi wn;d to Nava the r3•E) tz r0_ninium i_nducad-energy-lessloading when operating in t 1e ragicn of peak efficiency,t ip; di ffer•ance in power, coefficients for maximum efficiencymay be, attributed primarily to di`'far:;nces in profiledrag of the blad. sections at the inner radii. Th , r:,lsl,^ltsof comriztat'ons pr.;s::nt.,,d in refa.-ence 6 show that profile:drag has a large effect on the onti.mum plan form. Lossesin afficianc7 dUe to prcfil;: d.rar showy ,.zp as direct powerlosses and also as a corr•i, cticn (probably small) to tizainduced losses du-J to d:i.stchticn cf th wake.

In fi gure 24 the envelope curves of propellerafficiency for the NACA 10-(5) (08)-03 and l0-(5)((38)-03R

NACA R!k4 Yo. L^L27a 9

propellers at 1.3 50 rpm are compared with the optimumefficiency of a propeller with th-- Betz minimurl induced-an,rgy-loss loading. 'T:n-, curve of. opti:iur!1 efficiencywas calculated by a method neglecting all profile-drap, losses (r;;f ;r3nce 9) for a two-blade propel.lar oper-ating at the same values of power coefficient as waneobtained with the 1JACA 10-(5) (08)-03 nr-pallar. Thecurves in figure 24 shrew that the pro.filu-drag less--s arearproximat,ly 3 to 5 parcent graater for the cylindrical-shank nrcpall r than for th.- propu, ll.ar with affIcient air-fn il sharks, and the dlffaronc^j incr: asas with increasingvalues of advanc3 ratio and forward sp eeds. The .fficiancyloss du-,. to p rofile drab; for the propell.-ar vvitb efficienta l.rf'oil shames' is vary small. This raslzlt is in agre.-mant with th.; thanrotical analys::;s of prep-, 11,3r powerlosses nresantI-d in r.f;rencas 6 arid. 9, ',which slow thatthe thick inn--r• s--etlons of conventional cylindrieal-sliank propall^:rs are the chief sours- c blade:-dra t; loss,especially at high valu;; s of advance ratio.

^1ho highast afficiancy (appr ,-;tiimataly 0.95) shown infigure 24 for the "Tac-A l0-(5) (08)-03 propeller may not beachiava.d unl•ass the gain b ttiv,,-n the soinn_:r surface andtha wide shanks is k;:nt v.;ry small, as was don. in thewind-ti,nn,l t ^,st3. This would ba difficult to accomplishfor an actual installation rf a variable pitch prcpall::ron an airplane,, but semi mjans snould ba d,vis:.d whdr.bywida train blade-rc p t s.;ctions cruld ba uxt ;ndad to thesninnar surface. The d! ff,rnc.s bbtw,^-n th,3 c;ffici.nciesof th. ,q_CA 10-(5) (08)'-03 and prcpJll.rsare sufficidnt to warrant consid;i°able jffort in ov-, r-cominn both th. structural and the blade-spinner-junctureproblems encount3red for a practicabl.; design using; tnashank sctions of, the ;-ACA 10-(5)(08)-031 prop.liar.

^ffact rf compressibility on maxi.ra,zrr. sfficier.cy .-Tha variation of env.,lc-;e efficl.:Mcy with helical tipMach number is shown in figure 25 for the NTACA 10- (5) (08) -03and 10-(5) (08)-03R prrp all:r•s at tree diff.:,r.;nt test rota-tional speeds. The- varlat ?cn of air-stream Mach numb.:,rwith helical tip Mach numbz,.r at ach rctatIcnal spend isalso shown on fi _ ^.ir, 25. A curve joining the peaks of theaffici_ncy ;nv ,.:Iopas .frr aach prrt-^cll.:r wculO shov er themaximum _Me!-.,nc- obtai_nabla at any combination cf rota-tional sp,3d and air-stream IAach numb6r. Unfor•tunat,ly,the enN=:;lop p.a lz-s at soma of thu hi?h:,r rotational speedsw; ra not definitely aUtablishjd bjcaus ,,^ of the pow^;r

10 NACA RM No. L6L27a

lirr_itatiens previously mentioned * At an air.-straamMach. number of 0.35 the envelope effa cisncy c.f theNACTi 10-(5)(08)-03 propeller dropped 11 narcent for achange in helical tip Mach number from 0.90 to 1.03.The corresponding loss in envelope efficiency for thecylindrical-shank propeller was about 12 percent. Fora constant rotational sped tee envelope curves cfpropeller efficiency for tle two p ropellers diverge as-the helical tip Mach number increases with airspeed.At a constant rotational spend of 1140 rpm the differencebetween the env lop:e efl ciancy of the NACA 10-(5) (08)-03and 10-(5)(08)-03R nrcnellers increased 4 percent frr achange in helical tip Mach hi-Lmber frrm 0.60 tc 0.75.This comparison clearly shows the superLnrity of theprenellar with aerrd-namically efficient airfoil shanksat high values of advance .ratio and forward s peeds andalso shows that the losses due to inefficient shankections of conventional constant-spe:d propellers may beconsiderable at low values of .helical tip Nach number.

The familiar less in maximum efficiency due to com-pressibility is shown. in figure 26 for the twr propellerstested at a blade angle of 45o at the 0.75 radius. Thedata for the higher helical tip iv.ach numbers were obtainedfrom the results presentad in figures 1,'^ and 22. Themaximum effi_ciancy of the NACA 10-(5) (08)-03 propellerdecreased from abo,a.t 0.95 at a helical tip Mach number of0.70 to 0.73 at a helical tin Mach number of 1.14. Thecritical tip Mach number for this 22 percent less was about0.83. The corresponding decrease in maximum efficiencyfor the i^ACA 10-(5) (U8)-03R :-,ropeiler• was from 0.90 to0.65, or a loss of 25 percent. The critical tip Machnumber for tna cylindrical-shank propeller was also about0,83. ?At the high-.;st helical tip Mach number obtained inthe tests (M 1.23) the maximum fficiency of theN,tCA 10_(5)(58 :)-03R prnp::lle r was only 0.57. In figure26 tha variation of maximum efficiency with helical tipi'Naeh nurriber for a modal propeller (:^JtiCA 4.-(5) (08)-0::,reference 3) is shown for comparison. The diff^rjnce incritical tip Mach number fcr the full scale and modalpropellers is perhaps due, to the d fficulty in definitelyestablishing this print from the available data and doesnot n.cessari_ly indicate sari.eus discrepancies in thedata. It should be oointad out, however, that the full-scale tests were, extended to include higher helical tipMach numbers than those obtained in trio modal tests.

AIACA RM No. 56L27a 11

Cons tan t -powar =rjp 11°r oR^jraticn.- Airplanspropali-, rc cf.tan cp rata cvacan axtjnsiva ran^Ta ofadvance ratio at ccristant z-otatonal spJJd and torque.Since thia p(-w3r-absnrpticn nualitias of theNACA 10 - (5) (08)-03 p ronjller differ-dd from those of theVnC,^ l0-(,F5)(()3)-03R pro p ellar, the data w.,ra analyzedat several vall.ias of constant pcw:,r coefficient for aecristar,t rot:ati ,, nal s p a:.d rf 11 410 rim-,. `1'he results ofthis anal sis, peas. ntod i.n fi7ura 27, prrvide a b.:tt rly

comparison cf the affic;.ancy of t11; two prcp: , 11--rs thanand basad on advance ratio alone. kt a powar coefficientof C.15 (0.075 par blade) tha afficianey of the

ACIt 10 - (5) (Or?) -03R pro p ;,ll„r is alrricst the same as forthJ ^: yC y 10-(5) (03)-03 nrrp:;ll r at an advance ratio of0.J, but at an advance ratio of 3.3 thr, effici<;ncy cf thecylindrical-shank propell-.r is 14 p:;rcent l ss than theaf.f'ici;ncy of tha prop.11;;r p ith afficil, nt airfoil s}.anks.Similar results were repert-d in 4 and w,;reaxclainad by the Jiff Branca in load di.stributien shownby wake survj-7s. Th-- low lead-carryir_g capacity of thecylindrical shank s.;rtions of ccrnr,;ntional prcpallarsmale--s i^ necassary frr th.; rr.or, _.ff-lciant outboard s--ctionsto carry more lead, which may re ace.omplishdd at low speedswithout sz^rinus detrIrr ntA tit high spaads,how---v--r,, i- -ia high thrust loads for tha sJcticns of thaprrpeller that hav, the highdr rdsultant sactic . n speedsWU-1 cause aarli.r adv<;rsa compr--ssibility- affects crstall of th.s^ sjcticns. Tr-. aff.,ct of incr,:asing thevalue rf constant pc-w.,--r coefficient was similar fnr bothpropollers; the --ffici.r.cy was dacraas;d at the loweradvance ratios and was increased at th6 higher advancaratios. This eff-, ot is characteristic for all prop:;llars,and the superiority of t'hz3 idlaCA 10-(5) (0e)-03 prop;,llarover the prop3ller is d-,f initdlrillustrated fr y, both climb and high-sped conditions ofoperation. irr fi *ura 28 th. ^^ inn eff'ici ncy bc-twoen the two prrpalldrs for a constant r r-taticnal spendof 1140 rpm and a constant pcwdr coaffic? ;nt p:,r blade of0.1 is shown rv„r a range of airspeeds from 225 to 450miles p--, r hour. Over this rang:; of airsr:;eds the h6licaltip 'Vlach numb--r did not exc—d 0,79, and theNAbA 10- (5) (OS) -03 p ropulldr was from 2.8 to 12, percentmorn officiant than thJ NACU• 10-(5) (C8)-031 prcp.11.cr.

Comparisrn , ;ith r ^ul t s from mrd,^l fasts.- The modelof th- ' r•^t^ A 1G-T5 08 -C3 rrcp611jr'wac t.3st: din theL_inglay 8-foot high-spe)ud. tune 1. and the results are

12 NACA RM No. G6 *-j27a

presantad In reference 3. The data from the tests ofthis model rr•cnaller, which was 4 feet in diameter(?ACA 4-(5)(08)-03 nrcnaller), have been compared withthe data from. the tests of th. full-seal:; prrp:,1„l.Ir.F'i4ure 29 shows a c(-mparisen of the envelope efficienciescf the full.-scale and model propellers ov--r a range ofair-st y e-im Lach numbers from 0.175 to 0.56. T'-,-.-- envelopeefficiency of t12e full-scale pro-reller is higher thanthat of the model prcz all.er by 12 to 2 percent over therange of advanea r•atic from abcrt 0.8 to P.S. The diffar-ences over most of this range r.f advanc_- ratio ar•a perhapsw_thin the limits of expjr•imantul accuracy rf the two setsof data ., but the diffar;-Irices in ernaalrp_ afficiancy maypossibly be explain:;d as follo:^s

(1) Tha values of thrust for the full-scaleprrpallar ar, based co shaft ten sicn, whjraas the valuesfor the modal pr-p:111_,r are based on propulsiv_-- thrustand no allowaneJ is mad-- for tit:: change in skin frictiondue to the prop:,ll_-, r op.,ration.

(2) Tha heynolds numbers for the model tests werelower than those for th.; full-seal-- tz;sts.

(3) The spinn-, r diamat_;r was 0.217 of the prcpallerdiamc^t^er in the full-seal-, tlz sts and 0.333 of the propellerdiainet^_r in the modal t-,sts.

The characteri ti^s of the .full-scal y and modaloropallar.s are comnar , d in figure 30 by curves showingtha variation rf powr coc3fficient with thrust ccef-fic _ent at s:.-veral blade angl„s for thraJ vale-.;,s ofconstant air-strum Mach number, Such a comparisonalim _natas discr3parncl3s which might sh^w up as a resultof a slight diff ;ranee in blade-an Egla s.;tting. The curvesfor the two prcnall3rs ar in cics:; agraem_, nt, particularlyin th range of maximum effici-,ncy.

CONCLUSIONS

High-spa--d wind-tunnel tests of two full-seal:, two-blade pr n :ll.:rs hau„ been male for a ra 1F°e r, f bled„an g les frrn, 20 0 to 55 0 at airspa^3ds up to 496 miles perhour. The prop;;ll.:rs arj designat d by their bladedesign numbers, PIACH 10-(5)(03-03, which has

ITACA PM No. ,6 7127a 13

aerodynamically efficient air.ff^il shank sections, andNACA 1C-(5) (0;;) -^3 , wr_ich has thick cvlindrica.l 311anksacti_ons typical of convernticnal. blades. The resultsof ti ase tests and corr,_Dartsons witti results obtai,iedfrom pr--vi-us tests of a rredel pr•npaller (NACh a-(5) (O8)-03prcpallar) lad t o the frlJowlag ccnrlusi(,ns

1. Th-- l l i%CA 1C- (e) (08) -G3 and 10- (`,) (08) -03F, pro-pallars are vary afficiant, particularly fcr tha designcondi tion ^f operat'en. at a rctaticnal ti e.;d of 1550 rpmthe NAC,^ 10-(5)(03)-0'- prop;;l.lar aus an envelope jfficiencyof ap pr o ximately 0.95 at an advanc<; ratio cf 2.1. 1haanvelope 3f°ici_anc7 cf thu 10-(5) (08)-03F. nr r -) pellar isabut 5 -percent lass at th:: same valua rf ad^ u unce ratioand rotational sn e ac .

2 1Baced on constant ncw3r absori.;ticn (pcw;,rcoafficie nt of 0.1 p:r blade) and constant rrtaticnals peed (1140 rrm) tr3 v.,!'ti 10-(5) (08)-03 isfrom 2.8 to 12 r?or-^ --ffirient than th;;N,iCA 10-(5) (08)-03Fz pre pall-;r ov3r a range of air.spe3dsfrom 325 to 450 mils par hour. N'cr this rotationalspeed and ran 'ja of airsp;;:;ds the h:;lical tin Mach numberdo g s nest excdad 0.75.

3. T,;e criti_-;ul tin Much number for maximumaffici--ncy at tha dest-rn b1nde ant-;la of 45 0 is anproximatclyOo83 for both tha NhCA 10-(5)(08)-C3 and 10-(5)(O8)-O3Rprcp^llers.

4. The lose in maximum affici3ncy at the desi=rablade ang1a of 45 0 for tha 4.-.Cr, 10-(5) (08) -03 and10-(5)(0E)-O3z fi prop.:llars i^ about 22 and 25 parc;;nt,raspactiv3JIT, for an incr.;asa in h.;ltcal tir, ;each ru uberfrom 0.70 to 1.14.

5. The high dra7 of tna thick l.nnsr sacti.cns cifthe Ni-,CA prc-,,11ar was the chief source ofefficiency less, as p -:, c !ally at high val.u3s of adv_:nca ratiocorraspcnding to nigh for-nard sn;--ds.

14

NACA RM No. 16127a

6. The envelope efficiency obtained for the full-scale pr•orallar, NACA 10-(5)(08)-03, is higher than theanvalopa efficiency obtained for the model prcpaller,

FACA 4-(5)(08)-03 J by only 11 to 1 percent ovar a rangyof air-stream Mach numbers from 02175 to 0.56.

Langley Yworial Aeronautical LaboratoryNational Advisory Committse f o r naranautics

Lang,.l.ay .Fl d ld , Va .

P,IT ACA R?,^ T 7 o . F,6 !- 27a l5

S ln:^F F ,^',f C ^S

1.. :tank, John, Draley, lugene C., Delano, James B.,and Feldman, I,e lmis: Invasti,gati^n of Two-BladePropsl.lers at High Fnrward Spa^;, ds in the NACAB-Fnot High-Spend Tunnel. I - c,ffents of Com-pre s s ib alit: y . NxCA 4-'7 08-03 Blad e . T`IAC-A xCRNo . 410 19 1944.

2. Stack, John, Drale;;, Eugene C., Delano, James B.,and 'eldman, Liwis: Investigation of Two-BladePropellers at Hin:h Frrwar.d Speeds in the NACA6-Foot rfigh-ap;ed TPlnnel. TT - affects of Com-pressibility and Solidity. .'ACx 4-305-045 Blade.NACA ACR '1I^ . 4B16, 1944.

3. Delano, James B.:at HiF_-h ForwaSpeed Tunnel.pressibili.ty.4-(10)(08)-03

Investi g ation of Two-Blade Propellers-^d Sr-;ads in r.he iinCzI 3-F'oot High-

ITI - Effects of Camber and Coin-ACA 4 - (5)(OS) - ;5 and NACA

Elauas. vti hCr 'No. LE;F15, 1945.

4. Dilanc.,James B., and Carmel, Malvin M.: The Effactof Shank Design on Pr^pellar P •arforniance at HighSpe _ ds . ; "CA 'ALE No. L61X__-;,:, 1946.

5. Vogeley, A.J7.: Flight Measuramants of Compressi-bility Effects on a Two-Blade Train Clark Y Pro-paller. NACA ACR No. 3106, 1943.

6, Hartman, Edwin P. J. and Feldman, Lewis: AerodynamicFroblems in the Design rf Efficient Prnpkjllars,NACx ACR, Auk. 1942.

7. Glauert, F?.: The Glam3nts of Aerofoil and AirscrewThaery. Aml-rican _ d., Tr-e MacIvAllan Cc, . , 1943,pp. 222-226.

6. Ccorer, Morton: Comparison of Tests of a 4-F'oot-Diamater Propallsr in the Langluv G-Fact and 16-Fnot High-Spaad Tunnels. NACA JXR No. L5H31, 1946,

9. Criglar, John L. and Talkin, Harbert Charts forDetermining Propeller Efficiency. NACA ACR No.L4I29, 1944.

16 NACA RM No. T,6r,27a

T!kBT

Or -O Lt-iDE L\TGL^ AND IEOTATIO. I AL SP-,'Ej-'

Fi wg ^_lre, f hr tat. I —raa-1 EMade—An—,-le a,,S-,D a t3 d 0.75 radius, P0.75R

(deg)

i0-(5) (0-8) -03 or e 1 e r

8 1140 _5 40 45 50 55

1 7

9 1 131 50 20 25 30 1 3, 5 40 45 501

10 j 1500 45

11 1600 20 25 50 155 40 45

1 P if,on Of) 05 5 0 7 n

2000 20 25 50 3 5

211 00 2 0 2 3

21eO 20 5 150

Va r I a d I 4,51

;.' ? ACA 10- (5) (OP) -C"'7R

17 1140 75 40 45 50 55

18 1550 20 2,91 7-0 1 35 ' 4C 45 50

19 1500 11 4,5

20 1600 20 25150 s5 40

21 2160 2C 25 1 501

22 Varied I 1 4.5

C^

0

t-'

C'

Figure 1.- NACA 10-(5)(08)-03 propeller mounted on dynamometerin test section with tunnel open.

r•Orl

C)

0

Cr

Figure 2.- NACA 10-(5)(08)-03 propeller mounted on dynamometer ^'in test section with tunnel closed. '

NATIONAL ADVISORY COMMITTEE FOR AERONAUTICSLANGLEY MEMORIAL AERONAUTICAL LABORATORY - LANGLEV FIELD. VA

TUNNEL WALL

l 303 — -'

ED

,rr

C^

FAIRING FASTENED RIGIDLY TODYNAMOMETER HOUSING ANDSUPPORT STRUT O

—NOSE SPINNER AND PROPELLER SPINNERFREE TO MOVE AXIALLY, RESTRAINEDBY PNEUMATIC THRUST CAPSULE

NATIONAL ADVISORYCOMMITTEE fop AEWNAUTICS

FIGURE 3.- CONFIGURATION OF DYNAMOMETER FOR TESTS OF NACA 10-(5X08)'03 AND 10-(5X08)-03R PROPELLERS.

(7q

W

78

74 11.0

70 .9U

66 .8 }cU U

62 .7

OO58 .6

54 0 .5

O U)

50 a .4m °

46 .3 .24-U

42 .2a^

38 .1Lb

Fig. 4

NACA RM No. L6L27a

.64

.60

.56

.52

.48

.44

.40

.36

s .32

c .28ai

24a^

a^.2o

U_

} 16°

m

.08

.04

i

Developed plan form

I

II----- --- --I I -- Leading edges^^

Spinner locationI

I -

1 0

.09

, NACA 10-(5)(08)-03 propeller--- NACA 10-(5X08)-03R propeller

I

.08b/D

C .070 1 \ -

I - 1 \

06

3.05OId--

i-

Uo .04 h^bm

.03

.02

.01

0 0 0 .I .2 .3 4 .5 .6 .7 .8 .9 I.0 4 0

Fraction of tip radius, r/R NATIONAL ADVISORYCOMMITTEE FOR AERONAUTICS

Figure 4- Blade-form curves for NACA 10-(5X08)-03 and 10-(508)-03Rpropellers.

NACA RM No. L6L27a

Fig. 5

Figure 5.- Blades of NACA 10-(5)(08)-03 propeller.

NACA RM No. L6L27a Fig. 6

Figure 6.- Blades of NACA 10-(5)(08)-03R propeller.

NACj

(b) Blade sections at 0.3 radius. NATIONAL ADVISORY

COMMITTEE FOR AERONAUTICS

Figure 7.-Comparison of shank sections of NACA 10-(5X08)-03 and 10-(5X08)-03 Rpropellers.

0

r.r

1

(a)Thrust coefficient. NATIONAL ADVISORY


O-q

00

P)

-I--U-)

.02F-

00

.12

.10

08

o .06

04

14

2 4 .6 .8 1.0 1.2 14 1.6 1.8 2.0 2.2 24 2.6 2.8 3.0 3.2 34 3.6 3.8 40

Advance ratio , J

Figure 8. —Characteristics of NACA 10-(5X08)-03 propeller. Rotational speed,1140rpm0

.40

.36

I .32

U 28c

.24U

a^.20

0.16

a^ .12

08

04

F-^•

0'q

CDFigure 8 Continued. Rotational speed, 1140 rpm.

.2 .4 .6 .8 1.0 1.2 14 1.6 1.8 2.0 2.2 24 2.6 2.8 30 3.2 34 3.6 3.8 4.0

Advance ratio, J

00

z0

r

(b) Power coefficient.NATIONAL .ADVISORY


C^

Figure 8

Concluded. Rotational speed, 1140rpm.

NATIONAL ADVISORYCOMMITTEE FOR AERONAUTICS

(c)Efficiency.

r•

CID

C7

1.0 CG.8 L

Q^

6 E4 c

.2

00 .2 4 .6 .8 1.0 1.2 14 1.6 1.8 2.0 2.2 24 2.6 2.8 3.0 3.2 34 3.6 3.8 4.0

Advance ratio, J

z

1Zti

L-1

L-1

0

rr

C^

^.I2U,— .10a^v 08

o .06U

.04

.02

0 0 .2 4 .6 .8 1.0 1.2 14 1.6 1.8 2.0 2.2 24 26 28 30 3.2

Advance ratio, JNATIONAL ADVISORY

(a)Thrust coefficient. COMMITTEE FOR AERONAUTICS

Figure 9. — Characteristics of NACA 10-(5)(08)-03 propeller. Rotationalspeed, 1350 rpm.

r•

W

CPq

.28 -

.26 - --

. 24 ..

.22i\

.20

.I 8

c16

y

- _14 .

.12 ^- 4o

^ 08

.06T` n

.04 > >-- TL i LH

0 0 .2 4 6 .8 1.0 1.2f

141.6 1.8

711+1477\ _1

20 2.2 24 26 2.8 3.0 32Advance ratio, J

(b)Power 7C coe I f i c i e nt .

NATIONAL ADVISORYCOMMITTEE FOR AERONAUTICSCO

HL

Figure 9 Continued. Rotational speed, 1350rpm.

00 .2 4 .6 .8 10 1.2 14 1.6 1.8 20 2.2 24 2.6 28 3.0 3.2

Advance ratio , J

0

rrPO

(c) E I I I c Iency.

NATIONAL ADVISORYCOMMITTEE iOR AERONAUTICS

Figure 9 .-Concluded. Rotational speed, 1350rpm.

1.0 ^L

.8 a)

6c

4 c-

a

.2 >

.7

.6

5

4a^

3

W .2

.1

0

C^

0

.9'

d

.8

.7

6

c.5

0.4

W

.2

.I

.6 1.8 20 2.2 24 26 2.1

02

01

Fig. 10

NACA RM No. L6L27a

.24

.22

.20

. 18av

16ca^

a^ 1400

12

vc 10o'

08`cas

. 06

. 04

14

1.2

L0

$ E

C

6 v

4

.2

0Aavance ratio, i NATIONAL ADVISORY


Figure 10. — Characteristics of NACA 10-(5X08)-03 propeller.

Rotational speed, 1500rpm; ^60.75R 45°.

to

0

rrw

0 .2 4 .6 .8 1.0 1.2 14 1.6 1.8 20 2.2 24 26 28



U

ca)U

UOU

i

F—

(a) Thrust coefficient.

Figure I I. — Characteristics of NACA 10-(5X08)-03 propeller. Rotational speed , Oq

1600 rpm.

speed, 1600 rpm.

2 4 .6 .8 1.0 1.2 14 1.6Advance ratio , J

(b)Power coefficient.Figure II .—Continued. Rotational

.12U

.10O" .08

o .06I

04

02

0i0 z0

r

1.8 2.0 2.2 24 2.6 28NATIONAL ADVISORY


2(

18

16

aU .14

r•0^3

N

0r-{r

.2

1.0

8 ia^

6

4 S_a

2

0

10 1.2 1.4 1.6 1.8 2.0 2.2 24 2.6 2.8JAdvance rat io , NATIONAL ADVISORY

(c)Efficiency.Figure 11 Concluded. Rotational speed, 1600 rpm.

1.0

9

8

7

6

.5aU

4U

Li

.2

0 0 .2 .4 .6 .8

HUca^U

CllOU

NDi

n

a^

v0 .2 4 .6 .8 10 1.2 14 1.6 1.8 20 2.2 24



(a) Thrust coef f icient .

Figure 12.— Characteristics of NACA 10-(5)(08)-03 propeller. Rotationalspeed, 1800 rpm.

za

rIv

0 .2 4 .6 .8 1.0 1.2 14 1.6 1.8 2.0 2.2 24Advance ratio, J

NATIONAL ADVISORY

(b) Power coefficient. COMMITTEE FOR AERONAUTICS

Figure 12. Continued. Rotational speed, 1800rpm.

Uca^U_

4-4-

0UiN30o-

H

l 1

N

FHA^

L-I

C(H^

L

1

.2

.0^iN

8 EnC

6 c—Ua

4 ^>

2

T .^UCU_

U •^

W

o^

n

c^

0

1.8 20 2.2 24

\ CNATIONAL ADVISORY

\CJ Efficiency. COMMITTEE FOR AERONAUTICS

Figure 12. Concluded. Rotational speed, 1800rpm.

0

2 .4 .6 .8 1.0 1.2 14 1.6

Advance ratio, J

HU,-ca^U4- IUOUU)

C-S

NACA RM No. L6L27a Fig. 13a

Ir1

0 .2 4 .6 .8 1.0 1.2 14 1.6 1.8

Advance ratio, J

NATIONAL ADVISORYa Thrust coefficient. COMMITTEE FOR AERONAUTICS

Figure 13. — Characteristics of NACA 10-(5X08)-03

propeller. Rotational speed, 2000 rpm .

Fig. 13b

NACA RM No. L6L27a

.14

.12

v .10

.08

0 06

3 040

02

00 .2 4 .6 .8 1.0 1.2 14 1.6 1.8

Advance ratio , JNATIONAL ADVISORY

(h) Pr)WPr roa f f icient, COMMITTEE FOR AERONAUTICS.

tinued. Rotational speed, 2000rpm.

.E

U ^^CN

.^ q

w

.c

.I

c

i --

NACA RM No. L6L27a Fig. 13c

1.2

1.0

Z8 L

.6 E

4 UU

2

00 .2 .4 .6 .8 1.0 1.2 14 1.6 1.8

Advance ratio, J

r l CfNATIONAL ADVISORY

`C / LI ficiencyCOMMITTEE FOR AERONAUTICS

Figure 13. Concluded. Rotational speed, 2000 rpm.

12

.10

08w

C

06a^0,.. 04Nit'-- .0 2

00 .2 4 .6 .8 1.0 1.2 A 1.6

Fig. 14a NACA RM No. L6L27a


(a) Thrust coefficient. COMMITTEE FOR AERONAUTICS

Figure 14.— Characteristics of NACA 10(5X08)-03 propeller.

Rotational speed, 2100 rpm.

NACA RM No. L6L27a

Fig. 14b

.12

0

Q. .10U

w

.08

y..0 06U

3 .04Oa.

.02

0 .2 4 .6 .8 1.0

Advance ratio , J

(b)Power coefficient.

1.2 14 1.6


Figure 14. Continued. Rotational speed, 2100 rpm.

I r

'^ I .2

1- Ef r

Fig. 14c

NACA RM No. L6L27a

1.0

.9

.8

.7

.6

.5

v 4caD

.3W

2

0

2iN

..GE

LVv

0 .2 4 .6 .8 1.0 1.2 14 1.6

Advance ratio , J

NATIONAL ADVISORY

(c) Efficiency. COMMITTEE FOR AERONAUTICS

Figure 14. Concluded. Rotational speed, 2100rpm.

NACA RM No. L6L27a Fig. 15a

.12

.10

U.08

ca^U

.060U

N .04it~ 02

00 .24 .6 .8 1.0 1.2 14 1.6




Figure 15. Characteristics of NACA 10-(5)(0%03 propeller.


ca^Uv-NOULN30Q-

Fig. 15b

NACA RM No. L6L27a

0-U

W

0 .2 4 .6 .8 1.0 1.2 14 1.6

Advance ratio, J


(b) Power coefficient.

Figure 15. — Continued. Rotational speed, 2160 rpm.

a .,UCNU L

W

r

.L

NACA RM No. L6L27a

Fig. 15c

.i

C

Figure 15. Concluded. Rotational speed, 2160 rpm .

1.4

1.2

1.0 ^w

.8 EvC

6

Vv

4

.2

a.c^

w

^Ua^

OOU

30Q.

^vc

w

CIA

W

a^Ov

U)LL

.16

14

.12

.10

.08

.06

.04

.02


IfN

L; ! l 1 i! 1 1 i iET [, to J 01.8 2.0 2.2 24 2.6

Advance rat to , i NATIONAL ADVISORYCOMMITTEE FOR AERONAUTICS

(a)Air-stream Mach number at maximum efficiency, 0.611.

Figure 16. — Characteristics of NACA 10-(5)(08)-03 propeller

at high forward speeds. /6 0758 = 45.

1.4

1.2

w

c 1.0 2n^

8 Mw E

.6rv

.4

2

CLU

w

ca^

v=

a^0

30Cl.

cv

Uw

L

Z

wm0U

r

.16

.14

.12

.10

.08

06

.04

.02

NACA RM No. L6L27a Fig. 16b

I r%

1.8 2.0 2.2 24 2.6

Advance ratio l J NATIONAL ADVISORYCOMMiTTEE FOR AERONAUTICS

(b) Air-streom Mach number at maximum efficiency, 0.641.

Figure 16.—Concluded.

i^

1-

U .I 2

10U

08Q)O

.06

04

0- ;

0 .2 .4 .6 .8 1.0 1.2 14 1.6 18 2.0 2.2 24 2.6 28 30 3.2 3.4 3.6 3.8 40 42


(a) Thrust coefficient. COMMITTEE FOR AERONAUTICS

Figure 17. — Characteristics of NACA 10- (5X08) -03R propeller. Rotational speed,

1 140 rpm.

Oq

c^M^N

0r-{

r-a

1Z

0r

Jb _

32 L-- - -r -

iU.28

---I I I

,

n` -- 1-. _ ._ ... .^ . -14-1- - ^.

a> I - - -r- - _ -I ^_ I

t-,

.I2 - - -

441T.08

IR L

- -

-04

--

00 2 4 .6 .8 1.0 1.2 14 1.6 1.8 20 2.2 24 26 2.8 3.0 3.2 34 3.6 3.8 40 42




r•

Figure 17. Continued. Rotational speed, 1140rpm. °^

.0

8

Cll

.6

4U

.2

0v 0 .2 4 .6 .8 1.0 1.2 14 1.6 1.8 2.0 2.2 24 2.6 2.8 3.0 3.2 3.4 36 38 4U 42

Advance ratio, J

(c-) E1 1cl ency. .i

NATIONAL REVISORY

COMMITTEE fO11 AERONAUTICS

Figure 17. Concluded . Rotational speed, 1140 rpm.

c^

I

^Gi

r

C^

0

rrR^

.14

U .12

c.10

U.08

O.06

.04

.02

0

i'I

0 .2 4 .6 .8 10 1.2 14 1.6 1.8 20 2.2 24 26 28 3.0 32 3.4


(a) Thrust coeff icient.COMMITTEE FOR AERONAUTICS

Figure 18.— Characteristics of NAGA 10-(5)(08)-03R propeller.


POCID

La^

P

c-UUG

n

1^JN

0

rC

1.0

.9

.8

.7

.6

.5U

4U_

W2

I

0 0 .2 4 .6 .8 1.0 1.2 14 1.6 1.8 20 2.2 24 26 28 3.0 3.2 3.4

Ad vance ratio, J NATIONAL ADVISORY

( c) E I f I c 1 e n c y.COMMITTEE FOR AEROMAUTICS

Figure 18 Concluded. Rotational speed, 1350 rpm.

00

24

22

20

d.18U

e .16

o .14V

0 1 2Q.

c .100

U08

d

.06NOV

L.04

IE

02

3

3

1.4

1.2

a. 1.0 7-

:^ L

W Ec

3 .6 LV

.4

.2

Fig. 19

NACA RM No. L6L27a

0 i i 0 _— 1 0

1.6 1.82.0 2.2 2.4 26 2.8

Advance ratio , J NATIONAL ADVISORYCOMMITTEE FOR AERONAUTICS

Figure 19.— Characteristics of NACA 10-(5X08)-03R propeller.

Rotational speed, 1500rpm-, / 07513 -45°.

C^

0

t-^

t^

I-

Uca^U

Q)OU

rn

i

I'

v

0 .2 4 .6 .8 10 1.2 14 16 1.8 20 2.2

Advance ratio, v NATIONAL ADVISORY

(a)Thrust coefficient.COMMITTEE FOR AERONAUTICS

Figure 20. — Characteristics of NACA 10-(.5X08)-03R propeller. Rotational

speed, 1800 rpm.

Gq

0

.1611 441

.14-1

I I ^ -

ca_ 12I

.10^V I

o .08U

.0630

04I

.02

iltl N_.

00 .2 4 .6 .8 1.0 1.2 14 1.6 1.8 20 2.2


(b) Power coeff icient. COMMITTEE FOR AERONAUTICS

Figure 20. Continued. Rotational speed, 1800 rpm.

0

zc^

1Z

zG

rw

I.0

.9

.8

.7

.6

.5

4

U

Li

2

.I

0

H_

0

rrL^

P.2

.0^

.8 2E

.6 °U

40

2

00 .2 .4 .6 .8 1.0 1.2 14 1.6 1.8 20 2.2

JAdvance rat io , NATIONAL ADVISORY

(c) Efficiency. COMMITTEE FOR AERONAUTICS

Figure 20. Concluded. Rotational speed, 1800 rpm.Oz3

0

Fig. 21a

NACA RM No. L6L27a

.10

c) .084-C

x.0600U

04NiLE--.02

00 .2 4 .6 .8 1.0 1.2 14 1.6

Advance ratio, J

NATIONAL ADVISORY



Figure 21.— Choracteristics of NACA 10-(5X08)-03R propeller.


NACA RM No. L6L27a Fig. 21b

12

.10a-

0

C .08a>Uv-o .06U

i3 .040

a_

02

00 .2 .4 .6 .8 1.0

Advance ratio, ,J


1.2 14 1.6


Figure 21. Continued. Rotational speed s 2160 rpm.

Fig. 2].c

NACA RIA No. L6L27a

1.0

.9

.8

.7

.6

.5

4UCN

.3

w

2

.1

0

E7G

Ua

0 .2 .4 .6 .8 10 1.2 14 1.6

Advance ratio , J

NATIONAL ADVISORY(c) Efficiency. COMMITTEE FOR AERONAUTICS

Figure 21. Concluded. RototionaI speed, 2160rpm.

18

a .16U

c .14asUwv-

0 .12ULd$ .10

'O

O .08

U.06

UVV .040U

;? 02L

B

i' 1.4

1.2

w 1.0 Mw

UCY 8

^'^E

Ww

3 .6O

? .4

2

NACA RM No. L6L27a

Fig. 22a

10%

A i 1 0^ 00 I 2-0-

0 - 22 - 24 2.6Advance ra tio

NATIONAL ADVISOPYCOMMITTEE FOR AERONAUTICS

(o)Air-stream Mach number at maximum efficiency= 0.645.

Figure 22.—Characteristics of NACA 10-(5)(08)-03R propeller at high

forward speeds. = 4500.75R

. C►.U

cc^.0

U .14U

L4D

12

^v

o .10

w08

c.06.v

04

CA

t .02

01

Fig. 22b

NACA RM No. L6L27a

I.0

.9

.8

.7 1.4

.6 1.2

.5 1.0UC

L.4 .8

"- Ewc

.5 .6v0

.2 .4

.I .2

.0 10

Advance ratio , JNATIONAL ADVISORY

COMMITTEE FOG AERONAUTICS

(b) Air-stream Mach number at maximum efficiency =0.661.

Figure 22.— Concluded.

fi-__ - .

JtTfil

i

1.0

al

V.9

Cw

,0 .8ww

.7

0

C,

UCNU

w

(a) NACA 10-(5X08)-03 propeller.

b i3 W Iz Ifi I.b ID c)J 4. e- c4+ cb Gd av

Advonce rotio , J

(b) NACA 10-(5XO8) - 03R propeller. NATIONAL ADVISORY


Figure 23.—Envelope curves of propeller efficiency .

w

Fid

Oq

='.8

C

U .7y„ I

v-W

1.0

9 ^,.

Envelope efficiency of NAGA 10-(5)(08)-03 propeller, 1350rpm

— — — -- Envelope efficiency of NAGA 10-(5)(08)-03R propeller, 1350 rpm

--- Optimum efficiency of propeller with Betz loading

60 4 ,8 1.2 1.6 2.0 2.4 2.8 3.2

Advance ratio J NATIONAL ADVISORYCOMMITTEE FOR AERONAUTICS

Figure 24. — Comparison of the envelope efficiency of NAGA 10- (5X08)-03 and

36

10-(5XO8)-03R propellers at 1350 rpm with the optimum efficiency of

a two-blade propeller with the Betz loading.

z0CDrJP^

1.0

i .9a^

5 .8I`sa .72E .6

L .50

40c' 3U

2U_

W

Ernrelo efficiency of 1140 rpm I r Pm O rpm rP mP

2000 rpm

i100 rpm

NACA 10-(5X08)-03 propeller

NACA 10-(5X08)-03R propeller

\2160 rpm

Air-streom Mock number M

1 ITTr,

n

0

L

P

.56 .60 .64 68 .72 76 .80 84 .88 .92 96 100 104 108 1.12Helical tip Mach number, MT NATIONAL ADVISORY


Figure 25.—Effect of compressibility on envelope efficiency for NACA 10-(5X08)-03

10-(5X08)-03R propellers.

and

MC-,n

.9w

8

V

w .7

E2•E .Exa

Figure 26. Effec t

1 .Q

.54

NAGA 10-(5X08)-03 propeller— — — — NACA 10-(5XQ8)-03R propeller-----NACA 4(5X08)-03 propeller (reference 3)

.5

a_

CD

14

0rIv

.6 .7 .8 .9 1.0 1.1 1.2 1.3Helical tip Mach number M NATIONAL ADVISORY

^ t COMMITTEE FOR AERONAUTICS

of compressibility on maximum efficiency.

0.7 5 =45 .

1.0

.9

.8

.7

.6

TUc 4Uw

00 4 .8 1.2 1.6 2.0 24 2-8 3.2 3.6

Advance ratio , J

w 3

c- .5

2

CP =.10C=.20

P.15

.1020

All, 1A,

NACA 10-(5x08)-03 propeller

- - - - - NACA 10-(5x08)-03R propeller

Helical tip Mach number

Air- stream Mach number

04.0

.6

E4

.LUO

2 ^

1.0

8

NACA RM No. L6L27a Fig. 27

NATIONAL ADVISORY


Figure 27.— Efficiency of NACA 10{5X08)-03 and 10-(5X08)-03R propellers

at constant power coefficients and constant rotational speed of 1140 rpm .

Mt

Ca^ 8^U

.0 6

a^UC24

O2

i1 .0

c

.8 aa

.6v

Fig. 28

NACA RM No. L6L27a

14

,_ 12CUia10

_Difference in efficiency

--44500200 250 300 350 400

Airspeed, mph NATIONAL ADVISORY


Figure 28. —Variation of the difference in efficiencybetween NACA 10-(5)(08)-03 and 10-(5)(08)-03Rpropellers with airspeed. Constant propellerrotational speed, 1140rpm; constant powercoefficient per blade, 0.1.

1.0

8

C)

0

rw2

6 a^E

C

4 -c

0

2

7TUC

U+-.6LIJ

5

4 00 4 .8 1.2 1.6 2.0 2.4 2.8 3.2

Advance rat io, J NATIONAL ADVISORY

COMMITTEE f01Z AERONAUTICS

Figure 29. — Comparison of envelope efficiency for NAGA 10-(5)(08)-03 and

4-(5)(08)-0: propellers. (Data from reference 3.)

1.0

9

8

Envelope efficiency of NAGA 10-(5X08)-03 propeller

Zvelope efficiency of NAGA 4-(5X08)-03 propeller

Helical tip Mach number

Air-stream

i

Mach number

14

.12

w

CZ .10

w-a^

e 08i

06

:.J4

02

00 .02 .014

Thrust

.06 .08

coefficient, CT

.20

.18

16


------NACA 4-(5X08)-03 propeller

0.75R-- 250 -

I Z 20°

/i

10 .12


(a! I ]= O 20. NATIONAL ADVISORYCOMMITTEE FOR AERONAUTICS

Figure 30. — Comparison of chnracteristics for NACA

10-(5X08)-03 and 4-(5X08)-03 propellers. ( Data from

reference 3.)

NACA RM No. L6L27a Fib. 30b

00

P0.75R- 40°

350

30°

i


- ----NACA 4-(5X08)-03 propeller1 1 1 1 1 i

.02 .04 .06 .08 .10 .12

(.^ (^

Thrust coefficient, CT( U) M = 0. 35. NATIONAL ADVISORY

COMMITTEE FOR AEkONAUTICS

Figure 30: Continued.

.20

18

.16

14

0 .12

c: .10

.08

3 .0600-

04

02

02 .04 06 .08 .10 . 1 2

a) .06

.18

.04

.14

.02

20

16

00

1A0.75R= 145

/Z400/

i

/

NACA 10-(5X08)-03 propeller -- INACA 4-(5X08)-03 propeller11—i—L- 11 1 1 1 1 1_

4

x.1 2

wt^

.10U

0.08U

Fig. 30c

NACA RM No. L6L27a

Thrust coefficient? CT(c) 0.43.


Figure 30. — Concluded.

NACA RM L6L27a - Propeller Shanks

Documents

Transcript of NACA RM L6L27a - Propeller Shanks