REPORT No. 365

AERODIN4MIC CHARACIWIUSTICS OF CIRCULAR-ARC AIRFOILS AT HIGH SPEEDS

By L. J. BEIGGSand H. L. DErDEN

SUMMARY

The aerodynumie charachv-ietim of eight oircular-arcairfoils at speeds of 0.6, 0.66, 0.8, 0.95, and 1.08 time8the 8peed of 8ound hare been ddermined in an open+air dream $ inches in diameter, um”ngmodels of l-inchchord. Tle lower eurjace of each airfoil was plizne; theupper swface was cylindrical. A8 compared m“th themeasurements descm”bed in N. A. C. A. TechnicalReport No. 319 (Reference 1), the circular-arc airjoilaat 8peed8 oj 0.96 and 1.08 times the speed of sound aremore efia”ent than aiq%ils of the R. A. F. or (lark Yfamilies. At a speed of 0.6 times the speed of .wund,the thick circular-arc sections are extremely inefficient,hut thtk wcthas compare jarorably with those of theR. A. F. family. A moderate rounding oj the ~harpedges changes the characterisii~ rery little and b inmany instances benej-cid. The reiwdta indicate that ihesection of the bludee of propellers intended jor we athigh tip-speed8 8hou~d be of thti circulur-arc jorm forthe outer part of the blude and should be changed graduullyto the R. A. F. or Clark Yform as the hub is approached.

INTRODUCTION

In the course of the measurements of the aerody-namic characteristics of the 24 airfoil sections desoribedin Tecbmical Report No. 319 (Reference 1) of the Na-tional Advisory Committee for Aeronautic, the authomfound that it was advantageous to move the maximumordjnate of the section further back from the leadingedge as the speed was increased. A segment of acircular cylinder with the m&mum ordinate at 50per cent of the chord was found ta be more fioientat high speeds than airfoil sections of the R. A. F.or Clark Y families of the same thickness. It wasdeemed desirable to determine whether this increasedefficiency at high speed is characteristic of circular-arc sections of all the thickness ratios from 0.08 to 0.20times the chord and to determine the effect of roundingthe sharp edges, which would be nezcxx+aryin practice.These werethe object. of thework now ta be described.The measurements were carried out at the NationalBureau of Standards with the cooperation and fhanoiaIassistance of the hTationaI Advisory Committee forAeronautics.

APPARATUS AND EXPERL%lENTAL PROCEDURE

AirfoiIs,-The sections of the -8 airfoik used areshown in F~g 1. Each airfoil had a chord lengthof 1 inch and was 6 inches long. In conformity withthe notation adopted in TechnicaI Report 319 @efer- .—

R= L603

I

t =2. f 13

CA8

CA8a _

,. -----CA8h

--—

CAJ2

4= L /9/

CA12a

\= 1.300

CA12b

~c..

= 0.725

FIG= LJJ3M drfoll sectfons●

ence 1), the circuhir-arc sections are indicated by thecapital letters CA. The number following denotesthe thickness in hundredths of the chord length, andthe smaII letters following the number refer to thedegree of rounding of the edges. When the leadingand trailing edges of the section are sharp, no smalIletter is used. The letter a denotes that the height of

67

_..

. ...=

—

–--——

,,. —--

https://ntrs.nasa.gov/search.jsp?R=19930091437 2020-03-12T13:58:26+00:00Z

68 REPORT NATIONAL ADVISORY

the ci.rdar-arc above the lower surface at the leadingand at the trailing edge ia 0.01 times the chord length;the letter b denotes that the height is 0.02 times thechord length, CA8 is the airfoil called “ circulm-arcairfoil” in Technical Report No. 319.

Air stream, bahmce, nozzles,-The equipment usedis described in detail in Technical Report No. 319.The airfoils were mounted so as to span the cylindricalair stream, which was 2 inches in diameter. Measure-ments were made at speeds of 0.5c, 0.65c, 0.8c, 0.95c,and 1.08c, where c denotes the speed of sound at thetemperature of the jet. At 20° C., c is 1,126 feet persecond, and the corresponding airspeedswere 563,732,902, 1,071, and 1,218 feet per second.

Reduction of observations.—

NOTATION

p{ = absoluta static pressure inaide approach pipe(velocity prewure negligible)

Po = absoluti static pressure in jet (equal to baro-metric pres9ure)

pi –p, = impact pressure

v =speed of air in jetc = speed of sound at temperature of jetco = speed of sound at OUCP = density of air in jet

= MP V=velocity pressure> =mechanical equivalent of heatc, = specific heat of air at constant pressurek = ratio of specific heatsc. ‘ liftcoefEoientCD = drag coefficientA - area of airfoil taken as chord times exit diam-

eter of nozzle.L =liftD = drag

The following relations are derivedTechnical Report No. 255 (Reference

[ k-1.

in N. A. C. A.2):

9=’4’CVWE)‘ -’t(-1 k-1

jfp v,=288 X 0.00122651013300 J@@l&) ‘ 4

p,-po (1+ 0.19991 P /&) 7’2– 1— .gpv 3.5088 XU.19991 “V/cg

. . ..

The lift and drag coefficients are defined by theequations:

L

CL=~A

D

C“=j4p VA

COMMITTEE FOR AERONAUTICS

The quantities V/c, CL, and CDwero computed bymeans of these equations from the observod lift anddrag, the pressure inside the approach pipe, and thebarometric pressure.

RESULTS AND DISCUSSION

The results are given in the form of polar diagramsin Figures 2 to 9, incl@ve. Numerical valuea of thelift and drag coefficients for various angles of attackare given in Table L

A comparison of Figures 2, 3, and 4 and of Figures5,6, and 7 shows that the effect of rounding the leadingand trailing edges is small. The degree of roundingindicdied by a produces very little effect, tho differ-ence at positive lifts being within the experimentalerror, except perhaps for a slight increase in the dragcoticient at high lift coefficients. The greaterrounding of the b sections gives a further small in-crease in drag coeiXcient at high lift coefficients, but aperceptible decrease in the minimum drag coef3cient. ●

As a whole the rounding of the edges does not greatlymodify the efficiency.

& with other sections, the effect of thickness is verygreat. The thicker sections are much less efficient at --all speeds and the increase in drag coefficient withincreasing speed is greater for the thick sections thanfor the thin.

Figures 10 to 29, inclusive, ?how the c~~acteristicsof @cular-arc sections in comparison with airfoiIs -of the R. A. F. and Clark Y families, the data for thelatter being taken from N. A. C, A, Technical Report -No. 319. Each &me contains the curves for a singlespeed and a single thickness ratio. Figure 10, forexample, givw the curves for a thickness of 0.0S timesthe chord at a speed of 0.5 times the speed of sound.The circular-arc section is seen to compare favorablywith the corresponding R. A. F. section except athigh lift COS&iSllt9. It is not quite as e5cient as thecorresponding Clark Y section. Figures 11, 12, 13, and14 give the curves for the same sections at speeds of0.65c,.O.8C,0.95c, and 1.08c. At a speed of 0.8c (l?@&12), &e circular-arc section is appreciably better overa large part of the. working range than either of theother two. At a speed of 0.95c (Figure 13), it is de-cideQly better, and at a speed of 1.08c (Figure 14),the ~ag of the circuhi.r-arc section over a large partof the working range does not exceed 70 per cent ofthe drag of the Clark Y.

-.

Comparisons for other thickness ratios may be made _in like manner. Passing to Figures 25,26,27,28, and29 for a thickness of 0.20 times the chord, we find at .low speeds (Figures 25 and 26) that the circular-arcsection is extremely inefficient as compared with thecorresponding R. A. F. and Clark Y sections, At aspeed of 0.65c (Tigure 26), the circular-arc sectionbegins to show an advantage at large lift coefficient.This .& more pronounced at 0.8c (F@re 27), and atspeeds of 0.95c and 1,08c (Figures 28 and 29) the cir- -

AE130DYNMdIC CHARAOTERISTTCS OF CIRCULAR-ARC AIBFOILS AT HIGH SPEEDS 69

cukr-arc section is the beat over most of the workingrange. At a speed of 1.08c, the drag of the circulax-arc section within the working rmge does not exceed80 per cent of the drag of the Clark Y section.

These results indicate that it would be beneficial touse circular-arc aectioDs for the outer part of a pro-peIIerblade intended for use.athigh tip speeds, retainingsections of the conventional type nearer the hub wherethe thickness ratio is Iargs and the speed low. Thelength over which the circulax-arc section should beused depends upon the thickness of the blade and itsintended tip speed. The results of these tes@ shouldin any case be supplemented by measurements onactual propellers at high tip speeds, and in such teststhe best length could be determined. It seems notunreasonable to expect that a circular-arc section canbe used profitably over the outer third of the blade.

I

CONCLUSIONS .-

lt has been found that circukr-arc sections are moreeflicient at high speeds than either R A. F. or Clark Ysections. A moderate rounding of the leading and ~~_- –—trailing edges is not detrimental. It appears desirableto use circubm-arc sections for the outer sections of .. ...

.—

propeIler blades designed for use at high tip speeds.

ACKNO~EDGEWIN’l?

We V&h to acknowledge the ef3cienti assistance ofMr. P. S. Ballif in the conduct of the tests and in the

---—

. computation of the remdta...--—

BUREAU OF STANDARDS,

WMHINGTON, July, 19S0.

-l—(x— 04”-0 e 100-0 (316°+J+ti-00°0 06”-0 0 /2” -0 0 /8” -8 Q 22”@ 2._@ a) 8“-fD @ /4” -@ Q 20° -Q c) 24°

.95.6

.4

.2 -

0

-.2

0 ,0.5 Joc=

Ram 2.—Polar d@rma for drfoll CA8 for five V811MEof Tqc

+cY– 040-0 e /0”-4 a16°-O+tY-00”0 06”-0 0 /2° -0 0 18° Q 22” ‘(3 2“+3 (D%”* Q64°-@ ‘020° 024”

).95:

.8--5 0

.6

.4

c?’

o.5.

-.2

0 .0s Jo % .6 .20 .25 .30a=

FI(IUEX 4.-Pohr ~ fm afrfafl CA8b fw llva vahrm of WC

+ct– 040-0 e IOO-e 0160-0 i-u-00°0 0 60-0 0 12°-0 D 18”-0 Q 22”@ 2“+3 a) 8“4) @ /4° Q Q20”-Q a 24°

.6

.4

.2

0 -

?2 w.5.-Y ~ -2.00

0 ,05 ./0 .15~ .a .25 .30c=

litamt~ 8.—P0Iar diagram for afrfoil CA8a for five vaha of V/C.

— 04”-0 e 100-e G3/6°+r+ct–:%0 0 60+3 a /20-0 a /8°+ Q 22”

.80 2“- al 80-0 @ /4” -9 Q 2001+? 024”

.6

.4

CL

o

.5-.

720.05 Jo .15 .20 .25

c=.30

ElmM &–Pti dhm%mm& tifl CA12h 6Vb +abmo of W“

sVI

.’ I ,1 :

.

+a– Q /-0 Q 9 10” -e B/6 °-@+ct–00”0 06”-00 2’+

@ 1.2”-@ o /8° Q Q 22”

.8[ –- -..7 –:- .!! !Ol%__e. q.*- _,-Q-q,:,a 024”-“”” -~-l

,8- 24”

.6.65

,4

CL

.2 -

:5

-.20 m Jo ,/5 “’ ~m .25 .30

.6

.6

.4

CL

.2

0

-,2

G=

Frawn 6,–Polar rllw’ams for afrfoll CA12a for five vakrea of V/c.

I I I I IJo .15. ,20 .25 ,30

c.~OURX S,—Polar dhgrbraa for drfoil CA16 for fire valuaJ of ~J

;,65 24.

.6 -K95:P” y ..-~

.m” -fl ..

m“”.4 ~

,.--%-

C.‘%08

,2

0,5-’

:20.05 ./0 ./5 :20 .25 .30

~Dl?rau~ 7,-Polar dfagrmns for tircdiCA12b for five VMJM of Tqc

-Frx- : ::Q e /0=-0 : ;:;$ ;2$. -00°0 0 f2”-0

.80 2’-0 al 8“-(D (9 /4”* Q 20”+) Q 24”

.6

.4 -

a

.2

0

-.20.05” .10 ./5 ,20 .25 .30

c’,’,~muBx 9.-Polar dhgrama for afrfoU CA20 for five values of V/c

I I

+a– c)4°-o e 100 * a/6°-a+ci-00°0 0 60-9 a /2” -0 0 /8” -’0 Q ,22”@ 2“* d) 8“4 a /4” Q Q 20” -Q 024”

.6 .

.4

~ R.A.15--------1 1

~ Clark Y—-——

c=I

~ Circular urc

o +\

-.2 =

<200

0 .05 .10 .15 .20 .25 .39c=

Fmumi10.—Polar dhgrruns for airfofh 3 R8, C8, and CA8 for V/c. O.60. Maz or&-O.IB

-t

.6

.4

c“

.2

c

.-.<.0.5 Jo .

ti

24-e----- -

..-+----- ~_,---- *-

==+=- R./l. f.-.---.--I I—~ C/urk Y —————I I

~ Circular arc

.20c.

.25 .:

.t

.6

.4

c.

.2

0

:<

:$; 04 °-eel06°-001

~ 20+ (D8°-d) 19/

eI/6”-c+;-“-0 a 18” Q 22°“-s Q 20” CJ24°

*

24”---------0-------- --------Q

-- +—--+

c .----------

1.~ -——-1

T

/?.A.E

Clot-k Y —I

Cixulor orc

I

.20 .25 .:c“

FIGURE11.—Pofnr dfagmrw for WOW 3 R8, C8, and CA8 for V7c-O.8& Max. ord.-O.O3

.8

.6

.4

c=

.2

0

:2’

?

040-0 e ./0” -e:%6

0 16°0 60-9 @l f2° o 18° :25 -

@ 2“-0 a ‘8° 4 @ 14” 020° C)24° i

24°

//’ -

..#?=&

- fl.Af

~ Clurk Y—— -_I

I~ Oircuhr arc

> ,

I1 1 I I 1

.05J

JO ./.5 .20 .25 ..50G

3100’EE 13.-Pohr dlWUM for alrfds 3R8, C8, arid CA8 for W-O.96. Mu md.-o,m

-3ha

Pm URE Ei.-Pok di~ f(msh’fdfn 3 R8, C8, md CA8 for V7C-O.80. Mu m&-0~

.4

c.

.2

G

-72

l-d- cJ4’’-f3 e 100 @ 16” -l-a-00”0 0 6“-0 @ 12” Q /8° Q 22”0 2“-0 fD 8“ Q 14? Q 20” 024”

TA < ‘2 :’ ‘q

,— ——-

24°

s-r”.9*

A

d

-60

,05 ./0 ./5 .Zu ;25 ,GuCD

FImrRn 14,-Polar den for alrfolla 3R8, C8, and CAB far ~c-lld, Max, orrf,-O,t@

+d- 0 40-0 8 /0” -e a /6° -o +ci-00°0 0 6“-0 0 /2” * o la” -Q ; g“”Q29+ al 8“* a 14” -S Q 20° -Q e

.8

,6

.4 i

c’ - fi,A,~

.2 & ~,or; y—

4!

----

4n I

Cikcuhr or

o“%...

‘bw..

720 > P“ A,05 ./0 ,/5 .20 .25 .30

c=Fmuua 1O.—POIIWdlagraros for airfoils 3R12, C12, turd CA12 for ~c-0,66. Mu, md.-O.l2

.(

.6

.4

c.

,2

0

,.4

.6

.4

c!

.2

0

72

+ct– 04”-0 e 100-e a Il?e -a -I-*.00”0 0 6“-0

---0 ;2” * 0 18”-6 Q 2%(32** 0 8“-0 o /4” -&l Q 20” -Q 024”

.

I Iw ‘# I

-it——-—Clark Y

- 1“

+ “m., Cimuk7r or-c

h

. 1.

720”

.05 ,/0 ./5 ?20 .25c.

.30 .35

FIQUUE16.—Polar dhgrama h airfoils 3t?12, C12, and CA12 for V/c-OMI, Mu, oral,=0,12

o 40-0 @ /0” -9i:”; 0 60-0

0 /6” -o +d-0 12° -@

@ 20*o /80-0 Q 22”

d) 80-0 s 14”* Q 20” -Q o 24”1 1 1

. . . . . .. . .dd ——_—Cbr/f Y—

Circular arc

+ ~‘h

,a5 ./0 ./5 .20 .25 .30 .3:P.“

hwm 17,—PoIw dfagrams for slrfoll.s3R12, Cl 2, and CA12 for V/c-0,311, hfax. oral,-0,12

+ci- 0 4“+2 e 100-e00°0 0 6“-0 0 12°-00.2”+

.8 -rD 8°-rD @ 14°+

.6

.4

CL

.2

0-%.

h b w.$.*-9-. &w -w-/6’”

720 .05 .10 ./5 .2

c“

e /6° -o +d-0 /8° Q 22”020” D 24°

,

)-Q.

———.A-y..&-~ Z..924.

./a~.----~,~.. ,

RA.E [I

-------— ——-.

AI

C/ark Y

Circub ffrc

.25 .30 .35

MoumlS,-Polnr dfagramfor afrfofls3R12, C12, mdCA12for V/c-O.g& Max. orU..O.l2

+d - 04°* e Ioo-e00”0 06°m

a /6” + +d -D /20-0

@ 2** ar 8°4a 18”m ; $2;

.8G 14”4 020” -Q

1

\‘.. \ m 24°

.6-..

k -“P<.

~*--

d~,4 J .

d ?CL

$ $

.2

1———-

a Al“’-’’-.= —

Cimub of-c

o ‘‘%

&q -a-20 “

720.05 Jo .15 .20 .25

CD..w .35

3MUEX X).-l?olar dtagrsm fm alrhffa 3R16, C16, and CA16 fw WC-O.KI. Max, ord.-O.l6

o 4“-0 e 100:~”o O 60-9 @ /2”@20@ o 8“ @ 14Q

.8 -

.6

.4

c.

.2

0

720.G

I I.10 ,15 “ .

c..

a /6° +d -o 18° Q 22”Q 20° 0 24”

--l--i----

I I

~ ~. A. f.---------

—,- __T _ Clark Y—

~ CiFculor arc

_L1___.25 .30 ..5

FIcJum 19.—Polar dfsgrams for alrfolla 3R12, C;2, and cA12 forV/c-l,@., Maz ord.-O.l2

I I I .1--4”-1:240

1-720.(

:@+

‘1 n.........A. ——.—

-=--* ‘ A. --- I

1-a1-

1R.A.E

C/ork Y —

Cie& arcI

Jo ./5 - .20 .25 .30 .3CD

FIatmE 21.-P&r d&sma fm d.IfOfh 3Rlq C16, aad CA16 for V/c-O.6& Msx. ord.-O.l6

: 20~;012~5~,3

CD2’IWEE 22.-Polnr diagrams for drfolla 3R16, C16, and CA16for~c-O,&l, Max,ord.-OJ6

!0 -0 e 100 @ /6’0:0 0 /2° o 18° & 2%10 @ 14° Q 20° E)24”

. . . . . . ..-

——-—~ C/urk Y —

al Circular arc

4

-4”

-

c.Fmvm M,-Polar dhgmnu for alrfofh SRI 6, C16, ●nd CA16 for V/c4,~, Max. ord.-O.16

72J I I I.(25 ./0 ./5 .20 .25

c..30 ,35

hmmn 22,-Pohr dhgmnu for afrfolh SR16, Cl;, mid CA16 for V/c-O.96. Mar, ord,-O.10

.4jj:fl’ / (

c. ~ R.A.E------- . .

.2 b Clark Y —I -=3. _—T _

L. _ ‘w.W.m

‘+&w ~1 Cimu/ur arc“m.

o ‘-%.

‘w -72”--0 Q

-,20,G5 ./0 ./5 .20 ,25

Cn.30 ..3

B’mmm2E.-Pofsr diagrams for clrfolln3R20,, C20, and CA20 for V/c-O,&l, Mu. ord.-O.l6

-l–cY– Q 4“-0 e 100+ : ;:::00°0 06°-fJ

Q 22°Qg ;.2:g) a 24” 4)

@ ~o+) CD 80-0 020° -Q.8

26” +)

-+%

.6~.. .*&

--- - -

.4 I

CL!‘

.2* _ ‘-’-

---%

0 w w-*y a

72A.05 .10 .Is” .20 .25 .30 .2

c=FIa urm M,—Polar dlagrama for afrh[ls 3 R20, C20, and CA213for V/C-O.O& Mu. ord.-O.2O

+cY- 040-0 w /0” -e g m: :00”0 060-0 @ 12°-0 : 2?” -

.8@ 2“-(3 a)8°-o s 14” + 020-4 024”

I~ R. A.!--------

.6 — k Cbjk Ym 24Q-.

_—T—

.4

CL

,2

0 T*.*-S--* .*-

J -200

720.Qs ./0 .15 .20 .25 .30 .35

.6

.6

.4

c.

.2

L

.—.<.’

0(7”0 06”a 0 /2” -0 a 18°4 D 24”4Q 2** a) 8°-fb &l /4° -6) Q 20° * 26° +o 4“+ e 10* G O 160-0 Q 22° * 28° ~

~ R.A.)---------

– & Clurk Y——T—

~ CixL7r ore——

k“ ~

-28”

1 1 1 I , 1

Jo .15 .m .25 .30 .35c.

Blaum 27.-Pohr diagmms far airfofk 3R20, CEO, arrd CA20 for VYC-O.BO. MU ord.-O3O

+ci- 0 4“ e 100 0 /6°00°0 0 6“ @ /2° o 18° :2$’

.8@ 20+ a 8“ Q /4” Q 20” m 24°

I~ R.A.~

. . . . . . ..- 24”I.6 — ~ c/arf Y—-T-

~ Cimdor arc

.4

$.s”c.

.2 .

fo .

L-.20 J_.fo

=, ii-.

b h%’-2”

./’5 - .20 .25 .30 .35c= CD

Fm- z&-Pok dhgrams fa afrfofb 3R20, C20, and CA20 h V@-O.M. Mar. md.-O.2O FrouEB ~.—Pofu @a’amE for airfalb 3R20, C20, and CA20 fca ~c.=LOR Max. md.-O~

AJ3RODYI’TAMK! C!HARA~ERISTICS OF CIEC’CJIAWARC AIRFOILS AT HIGH SPEEDS

TABLE I

AIRFOIL CA8

L4ft Coemcientq CL

-J-I-I--U-LVjc -W -w –w –14” -w --1-1 !-Ion~-&-p-@-P

--–-+---l----l–-–+-----+-+---—-i -“% -“0l“’’’’’”

V/c PP4°608”l!Y W I 14” w w

! Drag ec-efaolenk+c.

AIRFOIL CA8a

—y—a

i

0,

i.

I I I 111 [11D- c&Eaients, CD

Lift mef%dent& CL (abore tsbbcontLnuedJ

TABLE I-Continued

AIRFOILCA8b

77

.—

I DX mefident& CD I

AIRFOIL CA12

. . .

LKtMemdmb C%I

4+ Lm‘ w‘I%,

*C -m -I& -16” -14” -I!P -w -’s” -& -4” -P— —

‘%&g,--: --.% zgl! m% :@ -’y’-%J ‘%J ~‘%J-. —. -. -. -.

Jf-t= - 3

.. . . . . —.. —-- .-. —--- ----- -. :Oa6

. . . . . . . . . . -.. -- .-. —---- —---- -. .W7

I Ding cOOmcfent&CD I

-

I

—

78 REPORT NATIONAL ADVISORY COMMITI’EE FOB AERONAUTICS

TABLE I—Continued

AIRFOIL CA12a

Lift COetlhient%CL

Drag WM1.cients, CD

am 0: El ~ O& mw o. 0s7 0.009 aosz 1“.(lb

O.o?qO.ow~;lJ o.lbl.061 .Wo .07c

:% :g.171

040 .048 .Wa .L27 . 17s:96 ::67 .Ow .W6

I.w. .074 .074 .Wi’w .(W .W4j

.1111, .lm ::2 :E!

AIRFOIL CA12b

Lfft cchchta, CL

<:: ““ ~ w

.-

Vfe –m” –18°

J+ -

“-l@ -14” -w –w -8° - 0“I

-i -w. — —

a60-:y. --pf4 -0.163-_:g -o. –a 079-a–.la -.

am,” ao7 il.166

–: 14a

7

:011.W, :% :;{ :%

.......

77:95------------ -:-? -z.-.. -I---- ----- --.:-. -. ‘ -. @l .W4

L~..... _.--- ------ ..-—- --.-— .-.-... .... .. ....... –. Ow .(KMt ! ,, 1 ,!. - I

Drag dclents, CD

rkyl 0.19’ CL]:? cL:4 o.q al o.A

.,Jg .’: 1 I ,;

I:Ij Ml& CM&o.~.

------- :m“ :116 ::93_.._._!!6 ...”2

.On .M1 .~

!

:046------ ----- ------ ..=-.. .m!

----------- ---—- --—-- ---- ------------ ---—- :& :%!

Lifi @@hlarI@ CL (almva table CDn@@)

;’ .]”” “q ‘ A

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