NASA AVRADCOM

Techmca} Memorandum 789'/0 Technical Report 78-38(PL) ....""t

(NASK-TM-78970) INFRARED SUPPRESSOR EFFECT N79-11043 "ON T63 TURBO._HAFT ENGINE PERFORMANCE (NKSA)14 p tiC AO2/MF A01 CSCL 21E

Unclas

G3/07 36980

https://ntrs.nasa.gov/search.jsp?R=19790002872 2020-03-22T02:22:48+00:00Z

.._...... _t , .... _...... l ._1_ I 1 I t _1 .... i I i i . i. _' ..... I I I _' C.._,_, I i 4 V

I ,i

I

SUMM2tRY , '

]

Tesl.s were ¢ondue|od to determine if th0re are performance penalties associated .:with-the instalhlt'ion of infrared (IR) supprossors on the T63-A-700 turboshaft engine...

Tile testing was done in a sea-level, static test nell at the NASA LOwis P_seareh

Center, The same el_no (A-E.102808 13) was rtul with tim staIldard OI.1_58 airer:fft

exhaust stacks and with the Ilughcs-desiga_ed, ejector-type IR supprcssm:s in order

{o make a valid comparison. Repeatability of the test results for the two config_ara-

tions, was verified By rertmning the conditions over a period of days. Test results

showed no measurable difference in performance betwe_tl the _.mdard exhaust stacks

and the IR suppressors.

1i INTRODIJCT1ON

J IRecent U.S. Army combat experience with helicopters has shown a considerable [ :threat to their survivability from infrared (IR) heat-seeking missiles. The prime I

,t _ source el: 1R radiation oma.heltcoptor is, of course, tlm engine exhaust, One approach

!] _ to the problem has been the development of devic_es that suppress file IR slg_mture t

i'!l _ by either cooling tho hot metal parts a_d the plume or shickting them from view. One _".I:_ V' !such Ill suppressor tlesi1231ed by Hughes for 1.11oT6q engine ix ml ejector-type device ,,

that simply replaces the standard OI.I-58 aircraft exhaust stacks: Althou#l such tte- t

vices improvo.,_urviv.lbility, they may impose performance penalties on the enKine.'.E

" In the tests dese-ribod ill this report, themffore, "i T63 ellgine was rtln with and without

i! suppl:essors to determine the performance penalties, if any. Tile testing xv:ts done at:!'l the NASA..£l_vis Research Center.q

\:'i A P PARAT1 !8 ........ "....'1

:l Engine

Tim T63-A-700 (fig. 1) is 't small i tlrbosha[.I eng'ine tlsod ill tho Army Ktowlt

O11-58 light observation helicopter, The o1112,illo hllS It pressure raiio of 8, a sin#e- t,

spool gas producer, and _1 free power I.urbino. At the takeoff rating, lh0 el_gine

deveh_s 'i tnaxlmUln of 236 ldlowatts (, 17 lip) arid has It gas-prodtlcer otttlet [¢,IlItR,r-V---

atur¢' of 1022 K (1380 ° l,'), EMerna| cotltrols consist el" it g_ls-producer Itlel cot_irol +.

h, vt, r and tl power-turl)iuo gllVol'nor level'. Ai power settings higher thall groutld idle, iiI, _ ,i

the engiut, is controlled by numipttlattng only tilt' power-turbine governor h, ver. Ex- !i

IllltlS[. is dtrt,ei.t,tl up,,v:trd l'l't)lll the t'll_2,illt, i]ll'ollgh tWO ducts. In the tlirt,l'aft installs ......

lion, two ,_llort, ctlrvt,d ('N]IlIII_i Stllcks nR}lllli directly on the t,nginc. As _]lt)V¢ll ill ,'

ligtlro 1, tilt' st_lmlal'd stacks are elliptic, snloothly curvt,d duels th:tt tttrt,ct lilt, ox- :I

! hatlsI backward alnloHI horizonilllly.1 'I

e

t '

1979002872-TSA03

F(W)act

I" (Wt_)c°r'r v_ ,_

. and- ..................................................

' (tl P)act¢,

(ltP)eor r '- V/_ ,Si.'1' where. 0 m_d 5 are the ratios of actual to st:mdard.temperature ,,rod pressurc_

I r_spoctivcly. Ftml flow was also s_aled to a referowat_mating value of .t2 831joules per gram (18 .i00 Btu/lb).

RES[ LTS AND DISCUS_qlON.!

The rcsu],ts of the T63-A-700 porfovnmnce tests with and withoul, IR suppres-

sors are presented in. terms of corrected fuel flow and power, lx, ast-squares

linear re_,n'cssien lines are drawn fllrough fl_e data. The correlation coefficients

for the linc¢_r regTession fits _,r¢. all better than 0.99. Wllen the data arc plotted

in tibia-rammer, an iuercasc in corrected fuel flow for the same corrected power _.

t indicates a loss in performance, _,': The results from three separttie runs with the stm_d:trd exhaust stacks in-

._ stalled are sho_xa_ iu fig_arc 6. The total number of data points, tim standard dcvi- II.atiot_ of the dat:1 about the regression line; trod the average percentage el devi'lt ion

[:!_. from the line are given in the figltre. Individual regression lines through the datat

\from each of the rams in this figure wotlld show a maximunl sprtwat of about 0.75 per-I:,i Celli I11performance level. This is a measure of the repeatability achieved. :

, ,I Test results from four rims wtih 111oIR sttpprossors inslallcd qrc shown in fig-

:; ure 7. The same statistical information is giv,,n here as ill l'iglu'e 6. Approxi- I

rim/ely the same lcvc] of repeatability was ,u,hicvcd with the IR stlppressors as wiih

tl_¢ standard exhaust slacks.

"i l,'i/_n'c_,lshow8 lilt'l'CSl.l]tsof 'Il'Ullwllhthe IR 814|;)}11'essorsinstalledbut with ihci ' outer ejectog.sln:ouds removed. These resulls agree wt:ll wiih those el lhc complete

I IR suppressor installation shown in fig_r¢, 7. In case of sizeable tlilh, rt,nces in per-

"! ' fOI'IIHI|ICt' bciweoll i|R' tlill|Idtll'd lll"Id ll_supprossor stacks, lhis run was illi¢'lR|cd It)

: separate lhc cjcclor el'feel from that of lhe IR suppressor prinmry nozzle a|ollt,.

I The pcrl'ovnmncc rcsulls with and wllhoul the Ill suppressors, al ready presenled

ill [lglll't',_ 6 tllll| _, :11'(' ropcalt'd ill 1"i/2.llr¢, I) l'Of czls¢' Ol ¢'Olllt_lll'isOI1. The dlllt, rcnc¢,

el los8 !h/Ill I/2 pcrl't, llt bt,lw(,oll lhe two ¢'on[Jgtll':liiOll8 t |oV¢']_ el |_t,l'l'orlwlnc¢, is well _'

wiihlnthe ]iluilsel repeaiabililyfor either¢'onljl2,111'lllJtHlalone, Within theaccur:u'y

:. 0|' lilt' dllitl, [h¢'1'¢'|'O1'¢', I10 Ill¢"ll,'qlll'HblU dift'crence in Pl, l'[orllHIIlt'_,, WllS o!)sCI'V¢'d,

i

1979002872-TSA06

' i

" ' -.... 1979002872-TSA08

iI

..j IC-76-3742

:1 Figure3.- T63engineteststandshowlrKJflywheel,waterbrake,andfacilityexhaustduct.

"I

,!

t

I ! 1t 1tlt!t I It'' ' ' i- q,T -' :_! -:7 -_• _ I t i1 . |

OI{IG|NA|, P;\_;k

'.i i"" II //

I i.I

' i

i:i '".... ' " r, _' '1""--.. ' :_, , ,, -, , '_ , ,; ,.. ', .'

I:i I '',, , ,,,'"', ''":'.b"jl,' i''''ll.:i 1c,; L,, I ' , [i.!. t_ll,, IIIP J _'_

_'i ' t,l¢lllh t"%ll,ll.lS| _'Ll.l_,| [ _l J_

/

"'! t i,,llll'l_ ,_, Mlll',milti_," ¢,f 101 t'll_lil't_' Lest ',l,md

!d

.,.I F-

"'i IIon,_'onst,ml,m ii I _tO

Iltqlllt_'Ol.lfd¢ t \\ -_-..._

'/',/! \\ ':i "" "_ X ; . ,_J,t|,,'1h I" u'h"olnl'h"_ dihlPl t'._ Ill t' till',:"i , I_xdh'dII_ tlll._IqdtR'

:: _ tlIPSMI¿ o

'_ i ' Ih'll _OllSJ,lllldll

' ! j Iqllll' " hlh'l l_'lll'mt_|l_ IIl_,jl ¿Ii_IPB|,IjIOI1

": i

1979002872-TSA10

", ....:, ......'--,-._-',-+_w.+....I,._+__+j+ + _I.._+++....++ + ' ' • +_

1979002872-TSA13

:! ORIL'_INALPAGe'.,l_£)P P("__),", '_l_._,I II'V