The effect of tip clearance flows on performance of axial flow compressors

T S^..ng% F: TT W*?. *P ' 3 _{*; AdL * -j t .} I-' --I- ", ,* ..

3 2 rj;.p

-

A '*'d -"- *. "~;L~&BL"p&4$J;;C~~ 'yL*f-:..'" 2 % i i

,*."\" --,t,.,c..--i,xn%p,PP~~ii-ii~~p, ,-+--Y1 ,4.:?.-> I y* S Z V - ; . . r T > . - 4 ----

P-2

i or ?..-sod . e S i c i e c y s$ a ;as t a r h i * e cj~cLe, it Be a.z&o.rr.atfc $&az

& t s e ~ o 6 - ~ - , 3 a r e ~ ~ ~ ; r & a % f ~ a B % i ~ I 1 e @ i ~ i e i % c y ~ & a ~ - = i r ~ ~ ; * ~ $ @ 1 ~ ~ ~ & ~ $ ~ ~ ~ f ~ ~ 6 ~ b ; ~ -7 ,

the cazTgra@oor are tE?.::cses due t o l e d c a g e Bows tCre=azzgh eke tip clearaaca. '1, 2, 33

1% ;x?,ae @ : l o Q ~ ~ k tinat t k a var%;i+tio of tip c I e b x 8 ~8 ha@ an %r*$-

portaa:t effect o i ym-fp &ad c:oi%presssr pasformai~se, P:3 ~jardieadar,

f ' 7 $

~&r.:crj""3:l%*e~~~ated fin detail the tip clesrasce Bkivg i m e c h & ~ i a ~ q eIId

variatf o i fia compree;;sor p a ~ f ~ s : : : ~ a n c a with tip clear&ce;e a e t 2 1 ~ deoizs2

-

,-

~ O rS"i@, W e k e inEro&ared

a

perfzct

a~d&

EITW .model and correctiora~ $or

real fluid af$ects to eoml2ara wit?? e : q ~ ~ ~ r i : z e n t ~ ~ 80 t h a t va?:iaa,$~ i n ~'ior~a-

gzeseor pex4sri--:arLc@ could be oszirnated $ 0 ~ ~ t h a r 0;$er&3.:rg eo~-dfj;lo:~a

a d other machinese

~"ile pr@oesiE invastijati9-I f e ssnesrnad with deter;i"s% %2lg the efdecl

o$ tPp cf@arza:~cs; @a;. c o ~ ~ ~ g s e ~ 1 - z o s p e ~ f o m n ~ ~ c e , 2ot 0;11y a0 Bsel2.l c s ~ ~ d i - -

eiafis, but also through a rn, gc sf 2 2 rate@ ~ ~from .tear @tall f=o -;..ell a h v e

d ~ g i g z . ~ for the p u r p o ~ e of gaining i x o r e a ~ ~ d e r @ t a i i & , q of the t i p Bow

n ~ s c h = ~ P @ ~ = &:d to e5ztej-id the

raSs'

~ e , of ~ 1 f 3 0 r n p a ~ r i m of t&@ @~~sri-b~lelrft@ with

-

_{IIYv -A a&@ " v * ^ - 4 ' " t/-'*l-gq *f_37--.}

--

ago ₁₉ fJes.*-; esxMic%cat (> 4 3, -f$* -&I - - - 5 - Q J a h ~ G % & , % C I L - L L

G,

&2r

" j " fi 94 ISe 20 ,, 0

~ ~ a g z e r *.* at, k k3. 4 9 Q n@ 51,yO

57,d"

EX.

RESULTS

Idk3$4ses ' k ; h r ~ u g ; ~ the i;let guidca vases should vary as t h e sguaye og

accor&,?g to the above criteria, u s i ~ l g the desig2-i flow rate value

as

o ba-

was n g t i i n a otrong w&@ at the d@sig;7 ,BOW ;?P&@, f$, is .felt that W&C@S

c f r c u ~ n P e r e ~ : ~ & axe raga, Tfxeref ore, ~ ~ o s e deedled sktrvayg %&en at the

d a o i g ~ :

sow

rate ars ave~agsd ci~ekaderer:%i&Iy asd assurasd ts v a v oa

2 Wotar PerXorma~ce

-

Averaged R e a ~ d t ~

. -%- -- ' '

--

-=---

The aversze

a0.e.s

crjcfBcie:nt i s Q e t a r n ~ i : ~ e d by ~ n w ~ m e r i c d h;1tegr8-

The vazk.i;-ekiar~ of average ?resoak-c cmaici@nt v ~ i t 9 tdp clearance a%

tJi'ee v a r f o ~ ~ Qrsw patee, as shwgxz i t 5 Fi~ure 23) i s @ @ B P to be B T P Q $ ~ C ~ V'd*

aeo plsetsd i x i ;%"iga%ra 6 h8we bwan referred $0 coai2?s%-n flaw rates before

being eras@ -gloBed i n Figuse 8, 'r3esugh 6 ~ r z t i ~ ~ the g e s - d t ~ :*ha8iv that

$he p~essure coeBiei@nt drops .:iaarl.jr. $Il~early At$ ir.rcr;s~lltg tip clear-

c8eara:ce is seen to bs ~ r e a g ~ ~ t a% t2ihr" lo-*@st SOVJ and d e c r e a a e ~

-

meagcre;ne:;ts, = ~ / $ ~ t z

'R

~3~

A o seen i n i p i ~ u r e 9. tilo aV@pa$@

S c e e o ~ f y oIIe eircw:&cra~atid e t a ~ o x x was s u r v ~ y a d be?k%d t LC rotor,

112 %vkLc:: &he ve;~s%ices are shed d s n y kke edges

of

%a sloe ~athsr~r tkwn a$ the t r a i l i r ~ g cdgu. PLmv visnrrlisaBo*- e q ~ r % n ~ e n t o by ~ a i n u ~ " h a v e ahow?

fae%s,

T . ~ B ~JOEQ the $ip cleara2ce ca:? be ei:ought of

az

%avl?,ia _{e 3} u~%forn%

V ~ Z O C ~ ~ Y

&--I t!:e dSrec6on a$ the C ~ O ~+~.*lxi~'P- P ~ ~ 5s cazried $hm~kgh b r m ~ ~ the

praBs;.trs to snc%feall-, ~ l d s aose;r&f&ly a ~ c h a 2 g o d $or Blade@ o+f amaJB thick-

ness, The vePos=fQ ger,>s.i.lae&ar

&o

$%@ ~ l ~ ~ r d $3

wllere p, a-.d p2 are s b t i c pressures on the pressure a d . suction side 0 4

P

d=sr~2p.;.eesoz, &his actio'ia te::&s to increase the pressure o ; ~ the p r e s s u r e

3, R ~ d w ~ e f i a$ ~ H a ~ k Irlput

---

'Zhe

f a c t ~ ~ ~ @%a$ caaas 2 zedactiasz

o,f

work f~xpuk $Y %gge rafmr due

to $1-p e$eara;~ce are:

(I)

911y~icay there be no work done by $22~

0"

RaAns, D e a l

A,,

"'Tip Clearance Flow@ i~ 343dd

Flaw

G ~ n % p r ~ s -

3QFB &36 pumpli4, cds~li~1i~ xnl@$u%e of %ydfc- dy_la=ic aad Fb",eci:&~ica E n g f n d ~ ~ P Y ~ Y LaBosa$sria o, Report

No,

5,

Fisi-y Conlrac:~ Hb-orl-012, ~askY9iJrrlcr 1"-4 a~d. BFZrd 9612,

[s-J.;;e 1954).

P J ~ U S ~ B ti, ~ ~ ~ a p a a , , u~2:pa &SP,WLL~S L$W R C ~ ~ I O I ~ B P ~ u

rs

~ ~ P ~ ~

.Par$ HHa

,

maw T ~ r b o " ~ w ~ a ~ h i ? ~ t ~ @ $ ~ Z d S ~ r ~ a i a Iaati@ate 0.f

T~eFfiollkogy, Z-Py4x+adgi:-~~x:fcs axxd ldsc&Waic<a Z:;xglna@r%ag Lab-. o r a t a x f e ~ , N a q Ca:.ztract Maaar-220$123), NR 097-0010 Rapart

i I

( 2 )

1

.-

I I

"

C i r c u m f e r e n t i a l a v e r a g e o f 4 r a d i a l s u r v e y s 7

o

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

f r o m a v e r a g e

a

S i n g l e r a d i a l s u r v e y

w i t h o u t c o r r e c t i o n 1

W

eu I

0. I 0 . 2 0 . 3

-

A v e r a g e f l o w c o e f f i c i e n t ,

$I

Average flow coefficient

,

d,

---_

i

1

-==I- --m- --

- --

- - - C a l c u l a t e d , no scraping

- - - _{C a l c u l a t e d with scraping}

0 0.004 0.008 0.012 0.01 6 0.020 0.024

Tip clearance / b l a d e h e i g h t ,

1

F l G . 8 A V E R A G E P R E S S U R E C O E F F I C I E N T A S A F U N C T I O N O F

0 0 . 3 4 3

A 0 . 4 0 0

0 . 4 5 0 ---- E x p e r i m e n t a l

- 0 0 . 5 0 0

--

Calculated, Eq. 3

A 0 . 5 5 0

_

-

C a l c u l a t e d , Eq. 3 f 9

I I I I 1

0

'

I I

0 0 . 0 0 4 0.008 0.012 0.01 6 0.020 0.024

Tip clearance / b l a d e height,

k

1.0 5 - - - -

3 A

a

@

2

@

Q-:i

0

o

m

El El

0 . 9

-

El

W

I

" >r 0

I

C

I

w

.

-

X

I

I

U

.- _{0 0 . 0 0 2 5} I I

-

0 )

0 . 8

-

A 0 . 0 0 6 4

L

o @ 0 . 0 1 2 9

I

I

t

o a 0 . 0 2 5 4

l

x

i

1

I

I

I

0 . 7 I I I I I

0 0.

I

0.2 0.3 0.4

-

0.5 0.6 Average flow coefficient

,

FIG. I 0 ROTOR EFFICIENCY AS A FUNCTION OF AVERAGE

1

0.7. I I 1 I 1 I i

0

0.004 0.008 0.012 0.016 0.020 0.024 Tip c l e a r a n c e / blade h e i g h t ,

X

FIG. I I ROTOR EFFICIENCY AS A FUNCTION OF TIP C L E A R A N E

I

I r o 0 6 a a d - O p C , O )

I _{r o ob a O Q C n m}

I

a El. a I* LC,,%,,

0

d o ; d d d

0 0 a e r l B T

CV

-

0 0 a3 r'- a

FIG. 16

-

A X I A L V E L O C I T Y S U R V E Y A H E A D O F T H E R O T O R A V E R A G E D O V E R F O U R

C I R C U M F E R E N T I A L S T A T I O N S ,

=

0.0025

1.1 1.0 0.9 0.8 0.7 0.6

.

0 0 0

o

0 0 ~ 0 0 0 0

00 0 0 0 0 0 0 0

0 0

-

0

1

0

i

0 0

0 0

1

-

0 !

0

I

0

0 O

I

-

O

/

I

0

I

I

8

oi

t

i

-

I

-

1 1 I

0.6 0.7 0.8 0.9 I .O

ld -3 • a 4

0

. -

4 /4

'iuai31jjao3 poaq j o i o l p a z l l o l o l o ~

4 4

a poaq l o i o j p a z l i o w ~ o ~

-

-

-

J-'( 0) _w

-

₀

a

IX)

-

-

0

-

-

_- 23, 0

0 - -.- -

*

a Ow.e--- i- - --- -- - - _- -

Q rn

I

h

a . e

*

.Bb FJ

n~ o c ~ r , 3

D C _X.

ec

0 I3 0

i A

0- QCPC) B LL

n

E rZl

1

₃ 5 Cr)

2

17 8 ' 0 -

i CK

5 . - G Q

,

a Q

i

sz

>

3 ag n !?$# C.

4 n f 6

i illr

s 4 n

1

w-3 4 3 0 LC

i

.

a

~7 j 3- K

6,

i

b-

B

0

9 I m2 2 0 Cc:

W

s, 130 w I

k-

7 833 m

tl]

ax

Ls)

0

ir

BIglij

3

dEf; i

-< 1 3

t- 2

- 4 0 m Z _LLJ

a

_CE

4 c

ma

5

-

2

a 1) 4 0

L

ii

c 1) 40 z .s$a

o

a

r-

z 9 % ca& 0

a

Z:

L cW.

%'

sea,

4

z

i; ee

C @a

&

_1--

G

1

3 0 3 0 N

C- 2s iw

2

.

a

-

.

* 3 t3

L "3. - Lt

-

-

-

G

/fi

/4

' ( u a ! 3 ! j j a o 3 p o a q lolo4 paztlowdoN

e

-0 -'J

-

0

m

BD k

rQ '3 9

-

-

-

-

- L2J 0

6

d

-

-

a

0

z

-

9

-

a

cn

W I-

a

o a 0

cr

0 B e

3

0 Q . 0 0

d

LC.

m

O Q e -3

I 0

rn

_{0 q e a} -

0 CE

q0.a

"

3

C r

a .a0 0

L L

E

0

E O S e I-

'icp 0

.

.

oa "a c)e:

0 . -

8 a0 + 0 Q D

0

% $

OD 0 I--

a e .a a g)c

cj

*

'9 d z m

0- .

-

a *

cn

tE

0 , 0

E iB, 3 bK

o a m .-

-a 3

D c l o o c.3

a

cc

I-

0 Q13 Z

W

-

0 am

-

C3

LL

0 - 0 CL

u r n

R h 0 b-l

5

6

d c s

PI a d - B , d- o g

a30 dlil C U C B O J ~

x 0 0 - w

6 1 . m

0 8 0 0

o d o o

==$

-I

<

00. 0

0

a u Q

Q + a

0 0 0

-

o Q u BPO k I -

U CJ C i W O

u .,a o

,

I

'a

0 % B

0 dl N

f'

-

6

OJ

r3 - 0 o", 00

-

-

-

-

a;

₃

0'

_c3

-

LL

4

/h

' J U ~ ! ~ ! J J ~ O ~ poaq lo(o4 paz!lourlobd

i

I

X

'-

Pressure d e f i c ~ e n c y

8

I

' i _{, "Flow}

s e p a r a t i o n doe to

! ( I

I

I\

1

f l o w e n t e r i n g a s h a r p

I

I\\

e d g e d o r i f i c e

I

I

:

1

I 1 \ I

I

I

'w-

R e a t t a c h m e n t

I

I

I

I '

L

DEFICIENCY FROM FLOW INTO A SLOT

FIG. 23

-

PRESSURE

FIG 24

-

V E L O C I T Y D I A G R A M SHOWING FLOW ENTERING

A N D LEAVING THE ROTOR WITH RELATIONS

,.

h

0

I

0 . 4 50 Rains' experimentai points

0 0.004 0.008 0.012 0.0 16 0.020 0.024

Tip clearance / blade height

, A

C

--

w

.

.

-

-v.

-.

.g 0.95 \ w

'+-

,

-*--

G I G .

31

COMPARISON OF CALCULATED AND EXPERIMENTAL

ROTOR EFFICIENCY AS A FUNCTiON

OF

TrP CLEARANCE FOR VARIOUS F L O W R A T E S

Y- w L 0 4- 0.90. w a 24 0 C w

1 -.-

---

-

-+-1.

-

-L. -2--

\

-v,-

i;;----

-\

'<-

-

-==---

-

-

-

--

-

- -

- -

-

--- _Experimental

P --

-1.00 _- Calculated

.\-

.

-