4- *g - nasa

E THE GA(W)-I AIRFOIL ~

l l u 1

&or Langley Research Cmter ~

~ - -- A T l f l N A l AERONAUTICS AND SPACE A GIN WASHINGTON, 0. c.

-

-2833

4 - * G

JUNE 1977

I 1. Report No. I 2. Government Accession No. I 3. Recipient's Catalog No

4. Title and Subtitle

FORCE AND PRESSURE TESTS OF THE GA(W)-1 A I R F O I L WITH A 20% AILERON AND PRESSURE TESTS WITH A 30% FOWLER FLAP

5. Repon Date June 1977

6. Performing Organization Code

7. Authorlsl

W . H . Wentz, J r , H. C . Seetharam, and K . A . F i scko

9. Performing Organization Name and Address

W i c h i t a S t a t e U n i v e r s i t y I Wich i ta , KS 67208

8. Performing Organization Report No.

WSU AR 76-1 10. Work Unit No.

505-06-33-1 0 11. Contract or Grant No.

12. Sponsoring Agency Name and Address

Na t iona l Aeronaut ics & Space A d m i n i s t r a t i o n

Washington, DC 20546

NSG-1165 13. Type of Repon and Period Covered

Con t rac to r Report

14. Sponsoring Agency Code

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

A i r f o i 1

F lap

A i 1 e ron

Pressure d i s t r i b u t i o n s

For sale by the Nat ional Technical In fo rmat ion Service, Springfield, Virginia 22161

18. Distribution Statement

U n c l a s s i f i e d - U n l i m i t e d

Subject Category 02

19. Security Classif. (of this report1 20. Security Classif. (of this page) 21. NO. o f pages

U n c l a s s i f i e d U n c l a s s i f i e d 3 4

22. Price'

$5.00

SUMMARY

Wind t u n n e l f o r c e and p r e s s u r e tes ts h a v e been conduc ted

f o r t h e GA(WJ-1 a i r f o i l e q u i p p e d w i t h a 2 0 % a i l e r o n , and pres-

s u r e t e s t s have been c o n d u c t e d w i t h a 30% Fowler f l a p . A l l

t e s t s w e r e c o n d u c t e d a t a Reynolds number of 2 . 2 x lo6 and a

Mach number o f 0 . 1 3 . The a i l e r o n p r o v i d e s c o n t r o l e f f e c t i v e - n e s s s i m i l a r t o a i l e r o n s a p p l i e d t o more c o n v e n t i o n a l a i r f o i l s .

E f f e c t s o f a i l e r o n gaps from 0 % t o 2 % c h o r d were e v a l u a t e d , as

w e l l as h i n g e moment c h a r a c t e r i s t i c s . The a f t camber of t h e G A ( W ) - 1 s e c t i o n r e s u l t s i n a s u b s t a n t i a l u p - a i l e r o n moment,

b u t t h e h i n g e moments a s s o c i a t e d w i t h a i l e r o n d e f l e c t i o n are s imi l a r t o o t h e r c o n f i g u r a t i o n s .

Fowler f l a p p r e s s u r e d i s t r i b u t i o n s i n d i c a t e t h a t unsepa-

r a t e d f low is a c h i e v e d f o r f l a p s e t t i n g s up t o 40°, o v e r a

l i m i t e d a n g l e of a t t a c k r a n g e T h e o r e t i c a l p r e s s u r e d i s t r i -

b u t i o n s compare f a v o r a b l y w i t h e x p e r i m e n t f o r l o w f l a p d e f lec-

t i o n s , b u t show s u b s t a n t i a l e r r o r s a t l a r g e d e f l e c t i o n s .

iii

I N T R O D U C T I O N

The h i g h pe r fo rmance p o s s i b l e w i t h t h e new GA(W)-1 a i r f o i l

and a i r f o i l - f l a p c o m b i n a t i o n s h a s been r e p o r t e d e a r l i e r ( R e f s .

1 , 2 , 3 ) . The p r e s e n t r e p o r t documents f o r c e and p r e s s u r e tests

of t h e a i r f o i l f i t t e d w i t h a 2 0 % a i l e r o n , and p r e s s u r e s t u d i e s

of t h e a i r f o i l w i t h a 30% Fowler f l a p .

All e x p e r i m e n t a l t e s t s r e p o r t e d h e r e i n were conduc ted i n t h e Walter Beech Memorial Wind Tunnel a t W i c h i t a S t a t e U n i v e r s i t y

SYMBOLS

The f o r c e and moment d a t a have been r e f e r r e d t o t h e . 25c lo- c a t i o n on t h e f l a p - n e s t e d a i r f o i l . D imens iona l q u a n t i t i e s are

g i v e n i n b o t h I n t e r n a t i o n a l ( S I ) U n i t s and U . S . Customary U n i t s . Measurements w e r e made i n U. S. Custov.ary U n i t s . Conver s ion f a c -

t o r s be tween t h e v a r i o u s u n i t s may b e found i n r e f e r e n c e 4 . The

symbols u s e d i n t h e p r e s e n t r e p o r t are d e f i n e d as f o l l o w s :

C

Cd

Cf

h C

R C

C m

C n

C P

A i r f o i l r e f e r e n c e c h o r d ( f l a p - n e s t e d )

A i r f o i l s e c t i o n d r a g c o e f f i c i e n t , s e c t i o n d r a g / (dynamic p r e s s u r e x c h o r d ) F l a p chord

C o n t r o l s u r f a c e h i n g e moment c o e f f i c i e n t , s e c t i o n moment/ (dynamic p r e s s u r e x c o n t r o l s u r f a c e r e f e r e n c e c h o r d 2 ) A i r f o i l s e c t i o n l i f t c o e f f i c i e n t , s e c t i o n l i f t / ( d y n a m i c p r e s s u r e x c h o r d )

A i r f o i l s e c t i o n p i t c h i n g moment c o e f f i c i e n t w i t h r e s p e c t t o t h e . 2 5 c l o c a t i o n , s e c t i o n moment/(dynamic p r e s s u r e x c h o r d 2 )

A i r f o i l o r f l a p normal f o r c e c o e f f i c i e n t , s e c t i o n normal f o r c e / (dynamic p r e s s u r e x c h o r d )

C o e f f i c i e n t o f p r e s s u r e , (p-p,)/dynamic p r e s s u r e

k c Cove l e n g t h

p S t a t i c p r e s s u r e x C o o r d i n a t e p a r a l l e l t o a i r f o i l cho rd

z C o o r d i n a t e normal t o a i r f o i l c h o r d a Angle of a t t a c k , d e g r e e s A I n c r e m e n t

6 R o t a t i o n o f s u r f a c e from n e s t e d p o s i t i o n , d e g r e e s

1

S u b s c r i p t s :

a A i l e r o n

f F l a p

p P i v o t m R e m o t e f r e e - s t r e a m v a l u e

APPARATUS FJJD TEST PJIETHODS

Model D e s c r i p t i o n

The GA(W)-1 a i r f o i l i s a 1 7 % maximum t h i c k n e s s s e c t i o n d e v e l -

oped a t t h e NASA Langley Resea rch C e n t e r (Ref . 1 ) . F o r tes ts i n t h e W S U two-dimens iona l f a c i l i t y , models are s i z e d w i t h a 9 1 . 4 c m

( 3 6 i n c h ) s p a n and 6 1 . 0 c m (24 i n c h ) chord . The fo rward s e c t i o n

o f t h e model w a s f a b r i c a t e d from l a m i n a t e d manogany bonded t o a

2 . 5 c m x 3 4 . 8 c m (I i n c h x 1 3 . 7 i n c h ) aluminum spar . Wing t r a i l -

i n g s e c t i o n s t o match e a c h f l a p and a i l e r o n were f a b r i c a t e d from

s o l i d aluminum as w e r e t h e f l a p s and a i l e r o n s . A i r f o i l and f l a p

o r a i l e r o n are mounted on 1 0 7 c m ( 4 2 i n c h ) d i a m e t e r end p l a t e s .

A s e t o f e x t e r n a l b r a c k e t s p e r m i t p o s i t i o n i n g of f l a p o r a i l e r o n

w i t h o u t d i s t u r b i n g t h e f low o v e r t h e model. Models a re f i t t e d

w i t h f l u s h tubes f o r s t a t i c p r e s s u r e s u r v e y s . Geometric c o n t o u r

d e t a i l s are g i v e n i n f i g u r e 1.

A s shown, t h e 2 0 % a i l e r o n model h a s i n s e r t s t o p e r m i t t es t s w i t h l e a d i n g edge gaps o f 2 % , l%, and 0 . 5 % chord . T e s t s were made

w i t h z e r o gap by s e a l i n g t h e s l o t w i t h c l o t h - b a c k e d a d h e s i v e t a p e

a p p l i e d t o t h e a i r f o i l lower s u r f a c e .

The Fowler f l a p h a s 3 0 % chord w i t h f u l l Fowler a c t i o n p o s s i b l e

as shown i n f i g u r e l ( b ) . The f o r c e c h a r a c t e r i s t i c s and o p t i m i z a t i o n

o f t h i s a i r f o i l - f l a p combina t ion have been r e p o r t e d i n r e f e r e n c e 2 .

Per formance w i t h s p o i l e r s h a s been r e p o r t e d i n r e f e r e n c e s 3 and 5 .

The p u r p o s e o f t h e p r e s e n t r e s e a r c h i s t o p r o v i d e s u r f a c e p r e s s u r e

d i s t r i b u t i o n and f l a p loads i n f o r m a t i o n f o r optimum f l a p s e t t i n g s .

A l l t e s t s w e r e conduc ted w i t h t r a n s i t i o n f i x e d by 2 . 5 mm (0.10 i n c h ) wide s t r i p s o f 4480 carborundum g r i t located a t 5%

c h o r d on upper and lower s u r f a c e s .

I n s t r u m e n t a t i o n

Pressure s t u d i e s are conduc ted by m u l t i p l e x i n g as many as 96

p r e s s u r e p o r t s t h r o u g h f o u r p r e s s u r e t r a n s d u c e r s by means of a s e t

2

of p r e s s u r e s c a n n i n g s w i t c h e s . The t u n n e l i s e q u i p p e d w i t h a semi-automated d a t a sys t em which c o n v e r t s a n a l o g f o r c e and p r e s -

s u r e o u t p u t s i g n a l s t o d i g i t a l form, and r e c o r d s t h e d a t a on

punch c a r d s . Computa t iona l a n a l y s i s and computer q r a p h i c s are done th rough t h e U n i v e r s i t y D i g i t a l Computinq C e n t e r .

T e s t P r o c e d u r e A l l t e s t s w e r e conduc ted a t a Reynolds number o f 2 . 2 x 1 0 6

and Mach number of 0 . 1 3 . L i f t , d r a g and p i t c h i n g moment d a t a

a re o b t a i n e d by d i r e c t l o a d c e l l measurements f rom t h e t u n n e l

main b a l a n c e . Drag d a t a are c o r r e c t e d f o r end p l a t e t a re d r a g

b a s e d upon wake s u r v e y d r a g measurements conduc ted w i t h t h e un-

f l a p p e d a i r f o i l .

Wind Tunnel The WSU Walter Beech Tunnel i s a c l o s e d r e t u r n t u n n e l w i t h

atmospheric tes t s e c t i o n s t a t i c p r e s s u r e . The t e s t s e c t i o n w i t h

two-dimens iona l i n s e r t s is 0 . 9 1 m x 2 . 1 3 m ( 3 f e e t x 7 f e e t ) .

Complete d e s c r i p t i o n o f t h e i n s e r t and c a l i b r a t i o n d e t a i Is are g i v e n i n r e f e r e n c e 6 .

TEST RESULTS

F o r c e T e s t s w i t h 2 0 % A i l e r o n

R e s u l t s o f th ree-component f o r c e measurements are shown i n f i g u r e s 2 t h r o u g h 4 f o r 0 % , 0 . 5 % , 1% and 2 % a i l e r o n gaps . C r o s s -

p l o t s o f i m p o r t a n t i n c r e m e n t a l e f f e c t s o f a i l e r o n d e f l e c t i o n are

shown i n f i g u r e s 5 t h r o u g h 7 .

These d a t a show t h a t t h e a i l e r o n p r o v i d e s p o s i t i v e c o n t r o l

r e s p o n s e € o r d e f l e c t i o n s from -60" t o +60° t h r o u g h o u t t h e a n g l e

of a t t a c k r ange p r i o r t o s t a l l . From t h e cI1 v s . a l p h a curves , it i s o b s e r v e d t h a t down a i l e -

ron r e s u l t s i n e a r l y s t a l l i n g , and c o n v e r s e l y f o r up a i l e r o n . T h i s

means t h a t c o n t r o l r e v e r s a l occurs a t p o s t - s t a l l a n g l e s o f a t t a c k .

While t h i s i s n o t a d e s i r a b l e c h a r a c t e r i s t i c , it i s t y p i c a l a i l e r o n b e h a v i o r , and i s n o t p e c u l i a r t o t h e G A ( W ) - 1 a i r f o i l .

P i t c h i n g moment d a t a r e f l ec t a nose-down t endency €or downward

a i l e r o n d e f l e c t i o n s . Drag da ta r e f l e c t a t endency toward g r e a t e r

3

d r a g i n c r e a s e f o r down a i l e ron t h a n f o r up a i l e r o n . T h i s d r a g

d i f f e r e n c e w i l l p roduce a d v e r s e yawing moments on a f i n i t e span wing. I t must be remembered, however , t h a t t h e p r i n c i p a l c o n t r i -

b u t i o n t o a i l e r o n a d v e r s e yaw is induced d r a g .

E f f e c t s of a i l e r o n s l o t gap open ing are i l l u s t r a t e d by com-

p a r i n g t h e v a r i o u s f i g u r e s . F i g u r e s 5 ( a ) t h rough 5 ( d ) show t h a t

open ing t h e gap from 0 % t o 2 . 0 % r e s u l t s i n o n l y v e r y s l i g h t de- g r a d a t i o n o f c o n t r o l a u t h o r i t y . C l o s e e x a m i n a t i o n o f f i g u r e s

3 ( a ) t h rough 3 ( d ) shows t h a t t h e most s i g n i f i c a n t e f f e c t o f gap open ing i s t o increase t h e b a s i c s e c t i o n d r a g w i t h z e r o a i l e r o n

d e f l e c t i o n . T h i s e f f e c t becomes more pronounced as l i f t c o e f f i - c i e n t i s i n c r e a s e d . Gaps o f 0 . 5 % and 1% a c t u a l l y i n c r e a s e cRmax

s l i g h t l y , e v i d e n t l y as a r e s u l t o f t h e boundary l a y e r e n e r g i z a t i o n

p r o v i d e d . A gap o f 0 . 5 % would seem t o b e a good compromise, p ro- v i d i n g a d e q u a t e c l e a r a n c e w i t h minimal p e n a l t y .

P r e s s u r e T e s t s w i t h 2 0 % A i l e r o n

P r e s s u r e s u r v e y s w e r e conduc ted f o r -10' t o +loo a i l e r o n w i t h

zero gap t o d e t e r m i n e whe the r gap s e a l i n g had any s i g n i f i c a n t i n - f l u e n c e ( f i g u r e 8 ) . Because o f t h e e x t e n s i v e t i m e r e q u i r e d t o ob-

t a i n p r e s s u r e d a t a , comple t e p r e s s u r e s u r v e y s w e r e conduc ted o n l y

f o r t h e 0 . 5 % gap c o n f i g u r a t i o n ( f i g u r e 9 ) . Comparison of f i g u r e s 8 and 9 shows t h a t t h e gap h a s l i t t l e e f f e c t on o v e r a l l p r e s s u r e

d i s t r i b u t i o n s . A i l e r o n h i n g e moment d a t a w i t h r e s p e c t t o t h e 8 0 % c h o r d h i n g e -

l i n e l o c a t i o n were o b t a i n e d by n u m e r i c a l i n t e g r a t i o n o f t h e s u r f a c e

p r e s s u r e d a t a . R e s u l t s o f t h i s a n a l y s i s are shown i n f i g u r e 1 0 .

The d a t a show t h a t t h e h i n g e moment v a r i a t i o n i s n e a r l y l i n e a r w i t h

a i l e r o n d e f l e c t i o n . The 0 . 5 % gap h a s n e g l i g i b l e e f f e c t on h i n g e moment. The a i l e r o n i s s u b j e c t e d t o l a r g e u p - a i l e r o n moments w i t h

z e r o d e f l e c t i o n a t h i g h a n g l e s of a t t a c k . T h i s i s a t t r i b u t e d t o t h e

r e l a t i v e l y l a r g e camber n e a r t h e t r a i l i n q edge which c h a r a c t e r i z e s t h e GA(W)-1 a i r f o i l s e c t i o n .

P r e s s u r e Tests w i t h 3 0 % Fowler F l a p

Optimum s e t t i n g s f o r t h e 3 0 % Fowler f l a p w e r e d e t e r r r i n e d from

f o r c e t es t s r e p o r t e d e a r l i e r (Ref . 2 ) . Subsequen t t o t h o s e t e s t s ,

4

a s l i g h t l y m o d i f i e d 40' f l a p s e t t i n g w a s d e v e l o p e d t o s i m p l i f y

f l a p t r a c k d e s i g n . The cR vs . c1 per fo rmance w i t h o r i g i n a l and

m o d i f i e d f l a p s e t t i n g s i s e s s e n t i a l l y t h e same, as shown i n f i g -

u r e 11. The p r e s s u r e d a t a p r e s e n t e d h e r e were o b t a i n e d w i t h t h e

m o d i f i e d s e t t i n g f o r 40° f l a p , and o r i g i n a l s e t t i n g s f o r a l l o ther f l a p d e f l e c t i o n s . E x p e r i m e n t a l p r e s s u r e d i s t r i b u t i o n s are

p r e s e n t e d i n f i g u r e 1 2 .

The f l a p cove on t h i s model h a s a f a i r l y a b r u p t e n t r y . Theo-

r e t i c a l a n a l y s i s o f t h e a i r f o i l - f l a p combina t ion ( u s i n g t h e method

of r e f e r e n c e 7 ) w i t h t h e t r u e cove s h a p e i n v a r i a b l y r e s u l t s i n a

computer p r e d i c t i o n o f f low s e p a r a t i o n a t t h e cove e n t r y . I t w a s e x p e r i m e n t a l l y o b s e r v e d t h a t t h e f l o w does separa te i n t h e r e g i o n ,

b u t r e a t t a c h m e n t o c c u r s ahead of t h e s l o t e x i t . S i n c e t h e p r e s e n t

t h e o r e t i c a l t e c h n i q u e s do n o t a c c o u n t f o r f l o w r e a t t a c h m e n t , i t w a s

d e c i d e d t h a t t h e e f f e c t i v e a i r f o i l c o n t o u r s h o u l d b e m o d i f i e d i n

t h e cove r e g i o n t o approx ima te t h e s e p a r a t i o n and r e a t t a c h m e n t .

F i g u r e 1 3 compares r e s u l t s o f a n a l y s e s u s i n g t h r e e cove c o n t o u r s w i t h an e x p e r i m e n t a l p r e s s u r e d i s t r i b u t i o n f o r 30' f l a p a t 1 0 . 3 '

a n g l e o f a t t a c k .

Based upon t h e s e r e s u l t s , a d e c i s i o n w a s made t o approx ima te

t h e e f f e c t i v e shape o f t h e f r e e s t r e a m l i n e w i t h i n t h e cove by a s t r a i g h t l i n e from t h e cove e n t r a n c e t o t h e 75% assumed r e a t t a c h -

ment l o c a t i o n . I t i s s e e n t h a t t h i s m o d i f i c a t i o n r e s u l t s i n con-

s iderable improvement i n t h e p r e d i c t i o n of p r e s s u r e s n e a r t h e a i r - f o i l t r a i l i n g edge . Two a d d i t i o n a l d i f f i c u l t i e s a r i s e i n u t i l i z -

i n g t h e t h e o r e t i c a l computing r o u t i n e . F i r s t , t h e c o m p u t a t i o n a l program may i n d i c a t e f low s e p a r a t i o n . I f s e p a r a t i o n i s p r e s e n t

a t 0 . 9 5 ~ o r f u r t h e r a f t , l i t t l e change i n p r e s s u r e d i s t r i b u t i o n i s e x p e c t e d , and t h e program r e s u l t s are p r o b a b l y v a l i d . However, i f

a s u b s t a n t i a l r e g i o n o f s e p a r a t i o n i s p r e s e n t , l a r g e chanqes i n

p r e s s u r e s are e x p e c t e d . C a l c u l a t i o n o f s e p a r a t e d f low cases i s beyond t h e c a p a b i l i t y o f t h e p r e s e n t computer program, and t h e r e -

f o r e c o m p u t e r - p r e d i c t e d p r e s s u r e d i s t r i b u t i o n s are p r o b a b l y i n -

v a l i d f o r t h e s e cases.

The second c o m p u t a t i o n a l d i f f i c u l t y i n v o l v e s a n a l y s i s o f t h e

c o n f l u e n c e of t h e f l a p and a i r f o i l boundary l a y e r s . I n a number

5

o f cases t h e program p r i n t s a " c o n f l u e n t boundary l a y e r e r ror"

message, i n d i c a t i n g t h a t s l o t f l ow v e l o c i t y and o u t e r f l ow v e l o -

c i t y are n o t w i t h i n l i m i t s s p e c i f i e d i n t h e program. No means

f o r o b t a i n i n g proper convergence f o r t h e s e cases are p r e s e n t l y

p r o v i d e d by t h e program.

F i g u r e s 1 4 t h r o u g h 1 7 compare t h e o r e t i c a l p r e s s u r e d i s t r i - b u t i o n s w i t h ' e x p e r i m e n t a l d i s t r i b u t i o n s f o r a number o f cases.

Normal f o r c e c o e f f i c i e n t s f o r a i r f o i l and f l a p o b t a i n e d from i n -

t e g r a t i o n o f s u r f a c e p r e s s u r e s are a l s o compared w i t h t h e o r y i n

t h e s e f i g u r e s . The agreement i s g e n e r a l l y q u i t e good f o r f l a p

d e f l e c t i o n s up t o 30' and a n g l e s of a t t a c k below s t a l l . F o r 40'

f l a p I t h e t h e o r y c o n s i s t e n t l y o v e r - p r e d i c t s t h e f l a p uppe r s u r - f a c e p r e s s u r e s I i n d i c a t i n g t h a t t h e f l a p boundary l a y e r i s t h i c k -

e r t h a n t h e t h e o r e t i c a l p r e d i c t i o n . U n f o r t u n a t e l y p r e d i c t i o n s o f s e p a r a t i o n are i n c o n s i s t e n t ,

and f r e q u e n t c o n f l u e n t boundary l a y e r e r r o r s w e r e e n c o u n t e r e d .

CONCLUSIONS

1. F o r c e and p r e s s u r e tests have shown t h a t a i l e r o n c h a r a c -

ter is t ics f o r t h e GA(W)-1 a i r f o i l are n o t u n l i k e a i r f o i l s w i t h more c o n v e n t i o n a l camber and t h i c k n e s s d i s t r i b u t i o n s . The a i r -

f o i l p r o v i d e s e x c e l l e n t a i l e r o n c o n t r o l e f f e c t i v e n e s s .

2 . Hinge moment c h a r a c t e r i s t i c s of an a i l e r o n a p p l i e d t o

t h e G A ( W ) - 1 a i r f o i l a re r e a s o n a b l y l i n e a r and o f e x p e c t e d magni-

t u d e s . The a i r f o i l a f t camber i n h e r e n t t o t h i s s e c t i o n does re- s u l t i n r a the r large u p - a i l e r o n moments, p a r t i c u l a r l y a t l a r g e

a n g l e s o f a t t a c k .

3. P r e s s u r e d i s t r i b u t i o n s f o r a 3 0 % Fowler f l a p a p p l i e d t o

t h e G A ( W ) - 1 a i r f o i l i n d i c a t e t h a t w i t h p r o p e r gap and o v e r l a p ,

a t t a c h e d f low can b e p r o v i d e d f o r f l a p d e f l e c t i o n s up t o 40°, a t

least f o r a l i m i t e d a n g l e o f a t t a c k r a n g e . P r e s e n t v i s c o u s f low c o m p u t a t i o n a l model ing i s i n a d e q u a t e f o r many p r a c t i c a l f l a p cove

d e s i g n s i n which f low s e p a r a t i o n and r e a t t a c h m e n t o c c u r .

A e r o n a u t i c a l E n g i n e e r i n g Department W i c h i t a S t a t e U n i v e r s i t y W i c h i t a , Kansas 6 7 2 0 8 August 1 9 76

6

REFERENCES

1. McGhee, R . J . and B e a s l e y , W.D.: Low-Speed Aerodynamic Charac- t e r i s t i c s of a 1 7 - P e r c e n t T h i c k A i r f o i l S e c t i o n Des igned f o r G e n e r a l A v i a t i o n A p p l i c a t i o n s . N A S A TN D-7428, 1973.

2 . Wentz, W . H . and See tha ram, H . C . : Development of a Fowle r F l a p Sys tem f o r a High Pe r fo rmance General A v i a t i o n A i r f o i l . NASA CR-2443, 1974.

3. Wentz, W . H . : E f f e c t i v e n e s s o f S p o i l e r s o n t h e G A ( W ) - 1 A i r f o i l w i t h a High-Performance Fowler F l a p . NASA CR-2538, 1975.

4 . M e c h t l y , E . A . : The I n t e r n a t i o n a l Sys tem of U n i t s - P h y s i c a l C o n s t a n t s and Conver s ion F a c t o r s ( R e v i s e d ) NASA S P - 7 0 1 2 , 1969.

5 . Wentz, W . H . and Volk, C . G . : R e f l e c t i o n - P l a n e T e s t s o f S p o i l e r s on a n Advanced Technology Wing w i t h a La rge Fowler F l a p . NASA CR-2696 , 1976.

6 . S i ew, R . : C a l i b r a t i o n of a Two-Dimensional I n s e r t f o r t h e WSU 7 ' x 1 0 ' Wind Tunne l . WSU AR 73-2, 1973.

7. S t e v e n s , W . A . , Goradia, S . H . and Braden , J . A . : Ma themat i ca l Model f o r Two-Dimensional Multi-Component A i r f o i l s i n Vi scous Flow. NASA CR-1843, 1971.

7

208c A i l e r o n C o o r d i n a t e s

Upper Surface L o w e r S u r f a c e

. o o o

. 0 0 5

.017

.035

. 0 6 0

.085

.110

.135

.160

. 1 8 5

.2 10

.235

.01960

. 0 3 7 5 0

.05000

.05286

. 0 4 6 4 6

.03988

.' 0 3 3 15

.026 39

.01961

. 0 1 2 8 7 -00609

-. 00070

L . E . Radius = 0 . 0 3 4 4 3 ~

-000 .01960 .005 . 0 0 3 7 5 -017 -. 01040 . 0 3 5 -. 01600 .060 - . 01200 . o a 5 - . O O G G O .110 -. 00560 -135 - . 00360 -160 -. 00250 .185 -.00260 .210 -. 00400 .235 -. 00800

(a) 20% A i l e r o n .

F i g u r e 1 - Model Geometry.

a

aJ

u \ Dl a O r ( P N 0 r( O P . 3 N O L m o o 0 0

5 c nj

c 0

(d u 0 d

u Ln ln InO \ m N W m (3, 0 0 0 0 0 (d . . . . . 0 1 0

U4 0 m c 0

0 n4 u l O c 0 N

u v m m w \ 0 0 0 0 0 * r

CJ a

m u l o w m m m o

\ O N N C J ~ ~ , . . . ' . a r5 U

X O .. a, c, 0 z

0 0 0 0 0 $4 0 0 0 0 0

w ,-4 c.1 m v

0 (3 c 3 0 0 0 0 0 0 0 0 0 0

07 o i c;. o ii) m 03 in m N c1 v 03 rl c1 c4 N d r- 0 0 0 0 0 0 0

I I I I I I I I I I I I I

'J L'J XI. 0 TI' 0 0 UY 03 U.3 U! LC 0 0 -, 'U

N 0 0 0 0 0 0 0 0 0 0 0 0 0 . . . . . . . . . . . . . a V O a J

m k

u O m 0 t n o m o U ! o U ! o m O \ c3 N in r- 0 m in I-- 0 N m I---0

!LA 0 0 0 0 r i r i d d c 1 " m m x . . . . . . . . . . . . . 0

w I-, . . . . . . . . . . . . . . .

I.,

9

\I

1 2

t-I , .005c Gap

S Y M & a - - 0 " 5 "

l o o 1 5 O

n 30 O 0 4 0 " 0 50 O 0 6 0 O

0

8 R. 2 0 "

-1

16

n 3 0 O n 4 0 " 0 50 O

Aileron Down

- 2

-1

L U

.02c G a p d / c \

SYM c1 -8 .0

-4 O

O 0

0 8 "

25

-8-00

-7.00

-6.00

-5l-00

C P

-4- 00

-3.00 I

-2.00

-1-00

0.00 .

1-03

A I L E R O N DEFLaZTIDN = -10-00 CEGREJS

MACH N3* = 0-13 "[xes m. = 2-2 E 06

SYMBOL ALFHA

+ -8 O X O0 D 160 v 2oo

Flagged Symbols Denote L o w e r Surface Pressures

\

(a) -10' Aileron, Large e ' s .

Figure 8 - Pressure Distributions with 0% Gap.

34

-8.00

-7.00

-6.00

-5.00

cP -4.00

-3.00

-2"

-1-03

0.00

1-00

+ 00 Y 8' D Eo v 16

( b ) -10" Aileron, Moderate a ' s .

F i g u r e 8 - Cont inued . 35

C P

-4.00

-3.00

-2.00

1-00

( c ) - 5 O A i l e r o n , Large a ' s .

F i g u r e 8 - Continued. 36

-8.00

-7.00

-6 9 00

cP -4.00

-2"

-1.00

0.00

+ 00 x 8' D v

t

( d ) -5' A i l e r o n , Moderate a ' s .


43-00

-7 -00

-6-00

-5*m

C P

-4.00

-3-00

-2-00

-I -00

0.00

1-00

(e) 0" Aileron, Large a's.

Figure 8 - Continued. 38

-8 00

-7 -00

-6.00

-5- 00

cP -4 00

-3.00

-2.00

-1.00

0.00

1-00

x 8' b eo 7 16'

( f ) 0' A i l e r o n , Moderate a ' s .


-8-00

-7.00

-6.00

-5 ao

cP

-4.00

-3.00

-2.00

I

-1.00 '

0.00 '

+ -8' X O0

v Eoo 16

w c 1-00

(9) + S o A i l e r o n , Large a ' s .

F i g u r e 8 - Continued. 4 0

-8.00

-7-00

-6 00

-5.00

=P -4.00

-3.00

-2.00

-1 -00

0.00

1.00

+ X go D 120 w so

X/C 1.00

(h) + 5 O A i l e r o n , Moderate a ' s .

F i g u r e 8 - Continued. 4 1

4ILERlJN OEFLECTIaV = 10=00 DEtREES

MACH M- = 0-13 "DS m- = 2.2 E 06

SW3OL ALPHA

+ -8 O

X O0 D 16' t zoo -7.00 .-

-6.00

-s. 00

C P

-4*00

-3 00

-2 * 00

-1.00

0.00

1-00

(i) + l o o Aileron, Large a ' s .

Figure 8 - Continued. 4 2

-B*oo I -7 00

-6.00

=P -4.00

-3”

-2 - 00

-1.00

S ” M a ALPHA

(1) + l o o Aileron, Moderate a’s. Figure 8 - Concluded.

4 3

-8.00

-7.00

-6-Do

-5.m

cP -4.09

-3.30

2.00

-1.00

c3.m

1.00

+ -BO x O0 b so v 20°

Flagged Symbols Denote Lower S u r f a c e P r e s s u r e s

( a ) -60 ' Aileron, Large a ' s

Figure 9 - P r e s s u r e D i s t r i b u t i o n s with 0 . 5 % 44

Gap.

-8.00

-7.00

-6.00

-5 00

-3 00

-2.00

-1.00

0.00

1 DO0

+ x b 1 2 O

16' ..

x/c -a0

(b) -60' A i l e r Q n , Moderqte a ' s .

F i g u r e 9 - Cont inued . 4 5

-8 00

-7 00

-6.00

-5 00

5 -4 00

-3.00

-2-00

-1.00

0.00

1.00

+ -ao X O0 so

2oo D v

k (c) - 4 0 " A i l e r o n , Large a's.

F i g u r e 9 - Cont inued .

46

-8.00 +

-7.00

-6-00

-5.00

cP -4-00

-3 00

-2.00

-1 =oo

O*oO

1-00

.

, *

'.

AILER#\I u n c i r r m =-4o-00 E- MACH M* = 0.13

R3Na-E M a = 2-2 E 06

S Y M B l l ALPHA + O0 % Elo

1 2 O 16'

0 v

1 - 8 0 x/c 1-00

(d) - 4 0 ' A i l e r o n , Moderate a ' s .


4 7

+ -8' x O0 b 16' 7 2oo

-5.00

=P -4.00

-3 00

-2. DO

-1.00

0.00

1.00 x/c BO m x/c 1.00

( e ) - 2 O O A i l e r o n , Large a's. F i g u r e 9 - Cont inued .

4 8

-8-00

-7 00

-6 00

-5.00

-4.00

-3.00

-2 00

-1-00

0.00

1-00

\

*=eo x/c 1-00

( f ) -20 ' A i l e r o n , Moderate a's. F i g u r e 9 - Cont inued .

4 9

-8.00

-7-00

-6.00

-3.00

-2.00

-1.00

-83

(9) -10' Aileron, Large a's.


-8.00

-7.00

-6-00

A I L E f X N EFLECTION = - I O * M 3

MACH NO- = 0.13 REYNOLOS No* = 2.2 E 06

SYMBOL ALPHA + 00 X 80 b 120 v 16'

'.

-5.00

cP -4 00

-3 00

-2 = 00

-1 *oo

0.00

1.00 c =EO X/C 1.00

(h) -10' A i l e r o n , Modera te a's.


5 1

-6 00

-5.00

=P -4.00

-3.00

-2.00

-1.00

1.00

(i) -5" A i l e r o n , Large a ' s .


5 2

-8.00

-7.00

-6.00

-5.00

cP -4.00

-3.00

-2.00

-1 =00

0.00

1.00

+ U x Eo 120

16' 0 v

0 8 0 wc 1-00

( j ) -5' Aileron, Moderate a ' s .


-e oo

-7 00

-6 - 00

-5-00

cP

-4 - 00

-3 00

-2.00

-1 00

0.00

1-00

+ -8 @

x O0 b 16 v 20

a

(k) O o Aileron, Large a's.

Figure 9 - Continued. 5 4

x c 1-00

-8 00

-7.00

-6.00

-5.00

cP -4.00

-3.00

-2.00

-1.00

0.00

1-00

+

8 l 2 O

x U

8 O

v 16

(1) O o Aileron, Moderate a's. Figure 9 - Continued.

55

ArL" U5LEc-r" = +5.m LEG-

MACH No- = 0-13 REYNOLDS M= = 2.2 E 06

S Y m ALPHA -8.00

-7 00

+

..

+ -80 x 00 0 16 7 20 O

-6-00

-5 00

=P

-4-00

-3.00

-2.00

-1 00

0.00

1-00 80 .€Q x/c 1.00

(m) 5 ' A i l e r o n , Large a ' s .

F i g u r e 9 - C o n t i n u e d . 56

-6 - 00

-5 00

cP -4.00

-3.00

-2.00

-1 00

0.00

1 a 0 0

AILERDN CEFLECTIDN = +5*00 E G =

' MACH NO- = 0.13 RCIN@LDS NO- 2-2 E 06

SYMBOL ALPHA + 00 x 80

12 O 16

0 0

i

- 80 .=Bo X K 1-00

( n ) 5 " A i l e r o n , Moderate a ' s .


-8.00

-7 =00

G.00

-5-00

-4.00

-3.00

-2.00

-1.00

0.00

1.00

L

X

b 2oo .c

9 8 0

I (0) l o o Aileron, Large a ‘ s .


-8 00

-7 = 00

-6 - 00

-5 00

-4.00

-3-00

-2 00

-1.00

0.00

1.00

x 0 120 0 16'

( p ) 10' Aileron, Moderate a's.


;1 x/c 1.00

-8.00

-7.00

-6.00

-5 00

=P -4.00

-3.00

-2.00

-1.00

0.00

1-00

-e O O0

+ x

16," 20

b t

-80

(9) 2 0 " A i l e r o n , Large a ' s .


-8.00

-7-00.

-6- 00

-5.00

=P -4.00

-3 00

-2.00

-1.00

0.00

1-00

c V x eo eo

16' b v

( r ) 2 0 " A i l e r o n , Modera te a ' s .


-8.00

-7 00

-6.00

-5.00

cp -4.00

-3-00

-2.00

-1.00

0.00

1- 00

SYMBO,

+ X

b 7

ALPHA -8 00 16' 20°

=80

( s ) 4 0 " Aileron, Large a ' s .

Figure 9 - C o n t i n u e d . 6 2

-8.00

-7.00

-6-00

-5 00

cP -4 900

-3 00

-2-00

-1900

0 =oo

AIiiERON E F L E C T I 0 \ 1 =+40-00 oEG9 MACH N3- = 0.13

"OLE NO- = 2.2 E 06

SYM3M_ ALPHA + O0 X eo

I 2 O

16 0 v

-8Q

(t) 4 0 ° Aileron, Moderate a's. Figure 9 - Continued.

6 3

.

-8.00

-7.00

-6.00

-5.00

=P -4 00

-3.00

-2.00

-1.00

0.00

1.00

1:: x b v 20

1 f

( u ) 60’ A i l e r o n , Large a ’ s .


-8 00

-7 00

-6 00

-5 - 00 cP

-4 00

-3 00

-2 00

-1 - 00

0-00

1-00

AILERON C€FL€CTIDN =+60=00 E G *

MACH M= = 0.13

Rc/NcLffi M= = 2-2 E 06

SYMBOL ALPHA + 0: x 8 0 12 v 16

(v) 60° A i l e r o n , Modera te a ' s .

F i g u r e 9 - Concluded . 65

F i g u r e 11 - L i f t comparison between modified flap geometry and original flap geometry, 6 f = 40'.

6 8

FLAP D E F L E C T I O N = 1 0 . 0 DEGREES

-8-00

-7-00

-6.00

-5.00

5 -4-00

-3.00

-2-00

-1.00

0.00

1.00

MACH NO. = 0 . 1 3

REYNOLDS NO. = 2 . 2 E 06

nnaoLALPHA + 0.20 X 5.2' D 10.3" 7 12.80

F l a g g e d Symbols Denote Lower S u r f a c e Pressures

W C 1.00

(a) 1 0 ' Flap. Figure 1 2 - Experimental Pressure Distributions.

6 9

FLAP DEFLECTION = 2 0 . 0 DEGREES

MACH NO. = 0 . 1 3

REYNOLDS NO. = 2 . 2 E 0 6

+ 0.10 X 5 . 2 O 0 10.3O

12.8O v

(b) 20' Flap. F i g u r e 12 - Cont inued .

7 0

-70 1-00

-8 00

-7.00

-6 -00

-5 -00

6 -4.00

-3.00

-2.00

-1 -00

0-Oa

1-oc

F L A P DEFLECTION = 3 0 . 0 DEGREES

MACH NO. = 0 . 1 3


SYMBOL

+ x 0 w

ALPHA 0 . 1' 5 . 2 "

10 .3 ' 1 2 . 7 "

9 -8.00 -

1.

(c) 30' Flap. F i g u r e 1 2 - Continued.

7 1

-8.00

-7- 00

-6.00

-5.00

5 -4.00

-3-00

-2- 00

-1.00

0.00

1-00

F L A P DEFLECTION = 4 0 . 0 DEGREES

MACH NO. = 0 . 1 3


SlMBOLALFliA + 0. 1' x 2 . 6 " b v

5.2 ' 7 . 7 "

10.3' 1 2 . 7 '

4

I, I

(d) 40' Flap .

F i g u r e 1 2 - Concluded.

7 2

-1

-1

7 3

F i g u r e 14 - concluded 7 7

Figure 1 5 - c o n t i n u e d

8 0

F i g u r e 1 5 - concluded

8 1

Figure 16 - continued

83

Figure 16 - c o n t i n u e d

8 4

Figure 16 - concluded

8 5

GA(W)-l w i t h 3 0 % F l a p

E x p e r i m e n t

_ _ _ - - T h e o r y ( R e f . 7 )

No c o n f l u e n t b o u n d a r y l a y e r e r r o r

(a) c1 = 0 . 2 0

Figure 17 - Experimental and Theoretical Pressures,40° Flap

8 6

F i g u r e 17 - c o n t i n u e d

8 7

F i g u r e 1 7 - coni ; inued

8 9

NASA-Langley, 1977 CR-2833

F i g u r e 17 - concluded

91

4- *g - nasa

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