7 5AJ

NASA TECHNICAL NOTE

CO10

NASA TN D-7753

t ,ft

EFFECTS OF LEADING-EDGE SWEEP ANGLE

AND DESIGN LIFT COEFFICIENT ON

PERFORMANCE OF A MODIFIED ARROW WING

AT A DESIGN MACH NUMBER OF 2.6

by Robert J. Mack

Langley Research Center

Hampton, Va. 23665

JAN 2 - 1975

,\

-

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON, D. C. DECEMBER 1974

1. Report No.NASA TN D-7753

2. Government Accession No.

4. Title and Subtitle' EFFECTS OF LEADING-EDGE SWEEP ANGLE AND DESIGN

LIFT COEFFICIENT ON PERFORMANCE OF A MODIFIEDARROW WING AT A DESIGN MACH NUMBER OF 2.6

7. Author(s)

Robert J. Mack

9. Performing Organization Name and Address

NASA Langley Research CenterHampton, Va. 23665

12. Sponsoring Agency Name and Address

National Aeronautics and Space AdministrationWashington, D.C. ^ 20546

15. Supplementary Notes

3. Recipient's Catalog No.

5. Report DateDecember 1974

6. Performing Organization Code

8. Performing Organization Report No.

L-9446

10. Work Unit No.

760-65-11-0211. Contract or Grant No.

13. Type of Report and Period Covered

Technical Note14. Sponsoring Agency Code

16. Abstract

Nine wing models were tested in the high-speed section of the Langley Unitary Plan windtunnel to study the effects of the leading-edge sweep angle and the design lift coefficient on aero-dynamic performance and efficiency. The models had leading -edge sweep angles of 69. 44,72.65, and 75.96 which correspond to values of the design Mach-number sweep -angle param-eter (j3cotA)DES of 0.6, 0.75, and 0.9, respectively. For each sweep angle, camber surfaceshaving design lift coefficients of 0, 0.08, and 0.12 at a design Mach number of 2.6 were gener-ated. The wind-tunnel tests were conducted at Mach numbers of 2.3, 2.6, and 2.96 with a stag-nation temperature of 338.7 K (150 F) and a Reynolds number per meter of 9.843 x 106.

The results of the tests showed that only a moderate sweeping of the wing leading edge aftof the Mach line along with a small -to -moderate amount of camber and twist was needed to sig-nificantly improve the zero-lift (flat camber surface) wing performance and efficiency.

17. Key Words (Suggested by Author(s))

AerodynamicsWind-tunnel modelsSupersonic speeds

19. Security dassif. (of this report) 2

Unclassified

18. Distribution Statement

Unclassified - Unlimited

STAR Category 010. Security Classif. (of this page) 21. No. o * 1 O"1 U* } p i C O < j h - U O C O f i ^ O C C f M ' ^ O ^ C M Cr> "-1 co o PJ o co cr *j- * PI * oi r1 PJ PJ oin m ^t s PI PI CM -) -i o c- c- c- c- C' o o

'

S " 2- ^, S t ^ ** r w S ? ? ? ? r , IM ^ r

c

co PI cc PI ff o 0' CD o r*- t PI p. p1. PP o* c

%4.- f U - ^ P . P i P l C M * - . O C - C C C C C : C

C

c o < ] -J r- M cr u u f^ co p. r- , - , - , - c ost *t U.

T3

I14O

OU

wWH

Q

WO

^HX, O

X

!HQ

4-

odaCO

DO

cQ> WE Uj._ 00>Q.X

LU

ooO

O

CMO

0)

h 730) 0)

TS T3

i "o^ CS O"rt U

"to '.

. 0>T3 *H

'g>O

roOr

CVJqi

qi"

0= '0 IDUl

'09

OQ

37

00)f-

r-

x OLU

toUJ

. oO

O /O D oot.3U)

0)N

Q.O

O0)

COIUO o>

0>T3

oo

CO

CO

M

GO

(0

o

CO(O

CVJ

0)

gW)rt

I

0

T3

rt-Hrtu.!-(

s1

OJ

CO

CD

GO (D

OO

CM _O

41

oo>

x O D O

CJ

CO{ilO

O

.COo

inuj

S! S

CM

00o

CM

00O

CD

esiII

CO

rtiioa

I %% %

r-H

rt

CO

aoIIra inH co

J9' &^< CO

o0

o

COUJQ

CVJ

0J-lo0)

t-i-H

0

be

CMO O

O

(0O

COoo

42

o0)

Q.X

UJ

V)UJQ

O

O D O

8 ~

COUJQ

O

00o

enUJQ

oJ

(O

CVJ

00o

(0

OJ

00o

COhO

0)

-i in co t- -S

M OOT .w '.

'rt 5 ?w ,. A

CD .

qro

CDcvj

cvjcvj

Q^J"

g -oRt T3g CS rtO

4-1hCD

(H73

aI

ICOi-H

0)'M

45

CJ toN-S-t0)

-4->

cvi oJ c\i

10N-

UJ0

ooca

iq

O

iSPrt

a0)

I

h0

|

Ort

o

T30)

ioO

CO

a>

IO

COrt

CO

46

CDO>

OJ

00o

COcvi

QLx

UJcnUJo

O D O

*r IOR CO 1^ O>

CVJ

00

y .s

a.**o

_l0

rr>VXO)T>

8

EO

.14

.12

.10

.08

0

4

3

2

1

0

-1

0

-.01

-.02

-.03

((3 cot A)DES

hExp.

.04 .08 .12

Figure 19.-Variation of CL, a, and Cm with design lift coefficientat (L/D)MAX and M = 2.6.

48

O)

CVJ

GOO

CO

caII

D

uio D

oo

O

O

Ono

c.O)

Q.XLd

OJ

COO

OJ

COo

nJO

3(-(bflrt

iu aQ

a

0)

s

o>TJ

rt^H

rtO

-

NATIONAL AERONAUTICS AND SPACE ADMINISTRATIONWASHINGTON. D.C. 2O546

OFFICIAL BUSINESS

PENALTY FOR PRIVATE USE *3oo SPECIAL FOURTH-CLASS RATEBOOK

POSTAGE AND FEES PAIDNATIONAL AERONAUTICS AND

SPACE ADMINISTRATION

PHILCO FOBD CORP

~TT?: TECHNICAL INFO SERVICES30 ADS

POSTMASTER : If Undeliverable (Section 158Postal Manual) Do Not Return

"The aeronautical and space activities of the United States shall beconducted so as to contribute . . . to the expansion of human knowl-edge of phenomena in the atmosphere and space. The Administrationshall provide for the widest practicable and appropriate disseminationof information concerning its activities and the results thereof."

NATIONAL AERONAUTICS AND SPACE ACT OF 1958

NASA SCIENTIFIC AND TECHNICAL PUBLICATIONSTECHNICAL REPORTS: Scientific andtechnical information considered important,complete, and a lasting contribution to existingknowledge.

TECHNICAL NOTES: Information less broadin scope but nevertheless of importance as acontribution to existing knowledge.

TECHNICAL MEMORANDUMS:Information receiving limited distributionbecause of preliminary data, security classifica-tion, or other reasons. Also includes conferenceproceedings with either limited or unlimiteddistribution.

CONTRACTOR REPORTS: Scientific andtechnical information generated under a NASAcontract or grant and considered an importantcontribution to existing knowledge.

TECHNICAL TRANSLATIONS: Informationpublished in a foreign language consideredto merit NASA distribution in English.

SPECIAL PUBLICATIONS: Informationderived from or of value to NASA activities.Publications include final reports of majorprojects, monographs, data compilations,handbooks, sourcebooks, and specialbibliographies.

TECHNOLOGY UTILIZATIONPUBLICATIONS: Information on technologyused by NASA that may be of particularinterest in commercial and other non-aerospaceapplications. Publications include Tech Briefs,Technology Utilization Reports andTechnology Surveys.

Details on the availability of these publications may be obtained from:

SCIENTIFIC AND TECHNICAL INFORMATION OFFICE

N A T I O N A L A E R O N A U T I C S A N D S P A C E A D M I N I S T R A T I O N

Washington, D.C. 20546