T S ..ng% F: TT W*?. *P ' 3 I-' --I- ", ,* .. *; AdL * -j t . 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* SZV-; . .rT>.-4 ---- L?:.: c. :.&i&# L>:<-*-.~- ,*i.;&"*,':a t.J.5 ,m L, ,&$.A> -- >a* .%*- * I::, td4 4*.jAS&.k~ *:.?j:;;2&3 3:2!5

2, 'Variatian wI"G:l Tip a e b r a t c s

P-2 i or .-sod ..? eSic ie cy s$ a ;as ta rh i* e cj~cLe, it Be a.z&o.rr.atfc $&az

&tse~o6 -~ - , 3a r e~~~ ; r&a%f~aB%i~I1e@i~ ie i%cy~ & a ~ - = i r ~ ~ ; * ~ $ @ 1 ~ ~ ~ & ~ $ ~ ~ ~ f ~ ~ 6 ~ b ; ~ -7 ,

the cazTgra@oor are tE?.::cses due to ledcage Bows tCre=azzgh eke tip clearaaca.

'1, 2, 33 1% ;x?,ae @:loQ~~k tinat t ka var%;i+tio of tip cIebx8 ~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 imech&~ia~q eIId

variatf oi fia compree;;sor pa~f~s: : :~anca with tip clear&ce;e a e t 2 1 ~ deoizs2

- ,- ~ O W rS"i@, e k e inEro&ared a perfzct a~d& EITW .model and correctiora~ $or

real fluid af$ects to eoml2ara wit?? e : q ~ ~ ~ r i : z e n t ~ ~ 80 that va?:iaa,$~ 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 fe ssnesrnad with deter;i"s% %2lg the efdecl

o$ tPp cf@arza:~cs; @a;. co~~~gse~1-zos p e ~ f o m n ~ ~ c e , 2ot 0;11y a0 Bsel2.l cs~~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 purpo~e of gaining i x o r e a~~der@taii&,q of the t i p Bow

n~sch=~P@~= &:d to e5ztej-id the raSs' ~ e , of ~1f30rnpa~rim of t&@ @~~sri-b~lelrft@ with

the ~ i 2 ~ " g e ~ t .fI?id. ~~~10d41 a id Q ~ i d C Q F ~ ~ C & $ ~ + , @ g i ~ e - 1 %AT FL@fere&zca 2.

- -- IIYv -A a&@ "v*^-4'" t/-'*l-gq *f_37--. ago fJes.*-; esxMic%cat (> 4 3, -f$* -&I ---5-Q

19 J a h ~G%&,%CIL-LL G, &2r

"j" fi 94 ISe 20 ,, 0 ~ ~ a g z e r *.* at, k k3. Q 51,yO 57,d" 49 n@

Angle

EX. RESULTS

Idk3$4ses 'k ;hr~ug;~ the i;let guidca vases should vary as the sguaye og

accor&,?g to the above criteria, us i~lg 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 cu~nPere~ :~& axe raga, Tfxeref ore, ~ ~ o s e deedled sktrvayg %&en at the

daoig~: 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 Qetarn~i:~ed by ~ n w ~ m e r i c d h;1tegr8-

The varia6:isn sf aperage presBure coe&%cisnt with average aovi

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 @@BP 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 in 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 decreaae~

- meagcre;ne:;ts, = ~ / $ ~ t z 'R ~3~ A o seen i n ipi~ure 9. tilo aV@pa$@

0 0

Scee o ~ f y oIIe eircw:&cra~atid eta~oxx was surv~yad be?k%d t LC rotor,

a small cl;ax~g~ Zn the psaosura zooEic5e~t will m-&ce z IB,XCB cUza,;ig~ $23 ef-

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 u~%forn% e 3

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

praBs;.trs to snc%feall-, ~lds aose;r&f&ly a~cha2god $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 ad. suction side 0 4 P

file blade a%zz~q- from, tE%e kip* in i ;nerd ua varfd~ &orz$ the chord,

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

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" Lire seduction oi Y J ~ P L %r.j<*:~t given bg the pzi.sssux& ue~sra~ca

J 'if-righ reference &Q P i p r e 23$ %& caa be ~k3~721. ,"I& doa-~g y =: 3,

RaAns, D e a l A,, "'Tip Clearance Flow@ i~ 343dd Flaw G ~ n % p r ~ s - 3QFB &36 pumpli4, cds~li~1i~ xnl@$u%e of %ydfc- dy_la=ic aad Fb",eci:&~ica Engfnd~ ~ P Y ~ Y LaBosa$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$W R C ~ ~ I O I ~ B P ~ u ~ ~ P ~ ~ rs .Par$ 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 ITcj, 6 [Ma,reh 1957j0

i I ( 2 ) 1 .- I I " I Tq. 25 / Ra1.26. &,rnpe 2% man% , Eq. 27 / ~ ~ ~ w i ~ l ~ ~ - i

Ci rcumfe ren t i a l a v e r a g e o f 4 r a d i a l surveys 7

o Single r a d i a l su rvey w i t h co r rec t i o n f a c t o r determined

f r o m a v e r a g e

a Single r a d i a l s u r v e y w i thou 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

FIG. 5 - A V E R A G E GUIDE VANE PRESSURE LOSS AS A FUNGTIQN OF AVERAGE F L O W

COEFFIC IENT

FIG. 6 A V E R A G E PRESSURE C O E F F I C I E N T VERSUS AVERAGE F L O W C O E F F I C I E N T F O R VARIOUS T I P C L E A R A N C E S

Average flow coefficient , d,

FIG. 7 AVERAGE WORK C O E F F I C I E N T VERSUS AVERAGE FLOW COEFFIC IENT FOR VARIOUS T I P C L E A R A N C E S

-----_

i

1

-=I=- --m- -- - --

--- Calculated, no scraping - - - Calculated with scraping

0 0.004 0.008 0.012 0.01 6 0.020 0.024 Tip clearance /b lade height, 1

F l G . 8 A V E R A G E P R E S S U R E COEFFIC IENT AS A FUNCTION O F

TIP C L E A R A N C E FOR VARIOUS FLOW R A T E S

0 0 . 3 4 3 A 0 . 4 0 0

0 . 4 5 0 ---- Experimental

- 0 0 . 5 0 0 -- Calculated, Eq. 3

A 0 . 5 5 0 _ - Calculated, Eq. 3 f 9

I I I I 1 0 ' I I

0 0.004 0.008 0.012 0.01 6 0.020 0.024 Tip clearance / blade height, k

FIG. 9 AVERAGE WORK COEFFICIENT AS A FUNCTION OF

TIP CLEARANCE FOR VARIOUS FLOW RATES

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 lx 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

FLOW COEFFICIENT FOR VARIOUS TIP CLEARANCES

1

0.7. I I 1 I 1 I i

0 0.004 0.008 0.012 0.016 0.020 0.024 Tip clearance / blade height, X

FIG. I I ROTOR EFFICIENCY AS A FUNCTION OF TIP C L E A R A N E FOR VARIOUS FLOW RATES

I I r o 0 6 a ad-OpC,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 - - - 6 0 0 s

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 OF T H E ROTOR A V E R A G E D O V E R FOUR 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 ti

- I

-

1 1 I

0.6 0.7 0.8 0.9 I .O

R a d i u s ra t io ,(

ld -3 • a 4

C C . C 4

0 . - c- at;:

4 /4 ' iuai31j jao3 poaq jo io l paz l l o l o l o~ 4 4 a poaq lo io 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

s4 n 1 0 w-3 43 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 a LLJ 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 & G

1-- 1

3 0 3 0 N C- 2s iw 2.a - . * 3 t3

L "3. - Lt

- - - G

$+ L i u a ~ 3 i j j a o 3 poaq i o j o ~ p a z l j o l u ~ o ~

/fi /4 ' (ua !3 ! j j ao3 poaq 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 am .- -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

ad-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 kI- 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 separat ion doe to ! ( I I

I \ 1 f l ow e n t e r i n g a sharp I I \ \ edged o r i f i c e I I : 1 I 1 \ I

I I 'w- Reattachment I I

I I 'L

DEFICIENCY FROM FLOW INTO A SLOT FIG. 23 - PRESSURE

FIG 24 - VELOCITY DIAGRAM SHOWING FLOW ENTERING

AND LEAVING THE ROTOR WITH RELATIONS

TO L I F T AND @ R A G

FIG. 3 0 - G R A P H I C A L DETERMI NATION OF BOUlalCikRY L A Y E R OlSPLAGEMENT THICKNESS 8*

,. 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

'+- , -*--

GIG. 31 COMPARISON OF CALCULATED AND EXPERIMENTAL ROTOR EFFICIENCY AS A FUNCTiON OF TrP CLEARANCE FOR VARIOUS FLOW RATES

Y- w L

0 4-

0.90.

w a

24 0 C w

1 -.- --- - -+-

1. - -L. -2-- \ -v,- i;;----- \ - -==----- '<- - - - --

- -- -- - ----- Experimental P --

-1.00 Calculated .\- . - - Calcula t ed with scraping

- - - - Rains' model with scraping