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Approved for public release, distributionunlimited

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Controlling DoD Organization. Bureau ofAeronautics [Navy], Washington, DC

AUTHORITYBUAER ltr, 31 Aug 1968; BUAER ltr, 31 Aug1968

THIS PAGE IS UNCLASSIFIED

CONFIDENTIAL21

i *-" zl

I _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

CO V F IDE NT I &L

ENCINURING CONSULTING4 SEHV ICES PERFMM) BY

BECCO OffE14ICAL DIVISI1ON OF FOCD MACHINEY AND

CHEMICAL CORP'ORATION IN CONJUINCTION WITH ALTONPROJ-ECT DEVELOir.-NT AT U.S. NAVAL ENGINEERINOEXPERIWNT STATION, AXNAPOLIS, AYTN

4 JUNE 19,5 - JUNE 1956

A Prepared byr

Willard A. Sanscrainte - Senior Development Engineer

James C. McCormick - Group Leader

Ralph Bloom, Jr. - Project Supervisor

Approved byt

Nosh S. Davin, Jr., Manager

Speria1 Projects

Reproductlom of this r ?or In any forin b/'"TII Joc,,,in! eJn$#,An WormjAmn fiT , 104P.M4ne Of Ikie lined l(3fe othe, thon No.iifltiV. k nvt outIhouited

1, 4, th.,, e -', i ot ' -I~ t t 19) 1 .d ,?. Its excect b!,'oczic approvol of ti.. 5.Cratary. ...'i .......,~ . h rized peso of )he Nony.

prcoo~biled b~y

31 August 1956

13ECC;O C4EMICAL DIVISION

FOOD JMACHINERY A0, CI{EYTCAL CORPORATION

ST1ATION B BUFFALO 7, N. Y.

C0N F ID EN TI Al CO'Y NO.

C 0 N F ID E N T IA L- - -- - - - - - -- -

FINI, L REPORT

COVER NG COINTRACT NOnr 1487 (00)

SNGThEIRING CONSULTING SERVICES PERFORMED BYBECCO CHEMIAL DIVISION OF FOOD MACHINERY AND

CHEMICAL CORPORATION IN CONJUNCTION WITH ALTON

PROJECT DEVELOPMENT AT U.S. NAVAL ENGINEERING

EXPERIIE:'N" STATION, .i'NAOLIS, MARYLAND

JTI;'E 1954 - JUNE 1956

Prepared by-

Willard A. Sanscrainte - Senior Development Engineer

James C. McCormick - Group Leader

Ralph Bloom, Jr. - Project Supervisor

Approved byt

Noah S. Davis, Jr., Manager

Special Projects

Itproductin, of this motor In ony f.rm by "This docunen conta;nt;nnform, '- .-.- i , mel,;tNnal defense of the United Statesather ti-,,, N - ,: ,;;le "' rized with h- , - ,, -f t4-[ . - . . . I I I .I -- - " . :, 7 1 n,-4 794. its

* xcept Ly wPoih *J pp)YzU trei -~ -S% r' r 0i -*~ -- l ,, .t - ' co !c ;ii ,I .iy rs..' :- i,. t ,ioriz ed p .ran ii

of th- 1,-, pohiblited by k-i.-

31 August 1956

3ECCO CHEM.ICAL DIVISION

FOOD )!ACIINERY AND CHE.T3AL CORPORATION

STATION B EITFFALO 7, N. :.

C0 N F I D E N r T A COPY NO. ___ ,

DSRBUTION LIST

Noe. 1-8 Chief of Nalaa ResearchDepartment of the NavyWashington 25, D.C.Attention: Code 429

No. 9 Chief, Bureau of ShipsDepartment of the NavyWashington 25, D.C.Attention: Code 320

No. 10 Chief, Bure-iu of ShipsDepartment, of the NavyWashington 25, D.C.Attention: Code 525

No. 11 Chief, Bureau of ShipsDepartment. if the NnvyWashington 25, D.C.Attention: Codo 551

Nos. 12-13 Commanding OfficerOffice of 1' val ResearchBranch Office316 Broadw-&,7New York 13. New York

Nos. 14-15 DirectorU. S. Nnave EcPr(p-.-.ment StationAnnapolis, "Y-l.. ,.nd

No. 16 Chief, Bureau of OrdnanceDepartment of the NavyWashington 25, D.C.AttentLion; Re6

No. 17 Chief, Bureau of OrdnanceDepartment of the NavyWashington 25, D.C.Attention: Ad3

Nos. 18-19 Commending OfficerU. S. Naval Underwater Ordnance StationNevort, Rhode Island

Nos, 20-21. CommanderU. S. Naval Ordnance Test Station, InyokernChina Laxe, CaliforniaAttention: Technical Library

CONFTDENTIAL

CO0N F TDE NT IA L

--DISTRIBUTION -LIST

No. 22 Commanding Officer & Director.A U. 3. NaIv@a Boiler and Turbine Lnboratory

Naval BasePhiladelphia, Pennsylvania

No. 23 Aerojet-General CorporationAzusa, CaliforniaViar Commnanding Officer

Off i,-e of Naval ResearchBranch Office103G East Green StreetPasadena 1, California

C IDEN

C ON F I D E N T IA L

-- TABLE OF, CONTENTS

Page No.

ii-AbstractI. :"Introduction 1

II.. Alton Chamber Analysis and Modification Recommended 3

Ill. Test System At EES 6

iv.. Preliminary Testing 9

V. Results of Test Runs and Conferences Held at EES

During the Test Programa. Conferences and Results of Test Runs #6-71-12B 13

b. Results of Test Runs 71 and 72-12B

Vie. Summary Discussion of Combustion Chamber Modifications 25

VII. Results of Combustion Tests Carried out at Becco 27

VIII. Conclusions and Recommendations 31

Tables

I. Test Data Run #68 Modified CC-12 Combustion Chamber 35

I. Instrumentation at EES 36

III. Run 5-12B Summary Data 38

IV. Data Before and After Temperature Changes 39

V. Data Summary Runs 71 and 72-12B 40

V1. Various System Pressures Additional Data - Run 72-12B 42

VII. Test Results - 90% HsO2 Decomposition Diesel Fuel 43

Combustion at Becco

Plates

1. Fuel Spray Pattern Used in Runs Nos. 1-6 at Becco - 44

Donut Baffle Attached

2. F uel Spray Pattern #70- 80 *onarch Hollow Cone Used in 45

Runs Nos. 7 and 8 at Becc

3. Fuel Spray Pattern #28 - 6 0 ° Monarch Hollow Cone Run No. 9 46

Becco Testa

C-- - -F T-D -

C 0 N F T D E T T A L

-.. ue :Sprav Pattern Solid Co'oe Run NO. 0 ng

Systems No.f 5

5. Fuel Spray Pattern Spraying SyTstems #3.5.Solid Cone Run 48

No. 11

6. Nitrogen and Aluminum Poivde Flow Pattern Through Plastic 49

Mockup with Ring Baffle Installed

Figures

1. Allis Chalmers 10" x 16" Conbustion Chamber

2. Modified Liner in Allis Chalmers 10" x l6"' CombustionChamber (CC-12 Chamber)

3, Modified Fuel Injector Used in Hull Mockup Test Runs

Nos. 69-80

4. Modified Liner in CC-12 Combustion Chamber Used in Test

Runs Nos. 76-80

5. Engineering Experiment Stp tion Designed CC-13 Combustion

Chamber Used in Test Runs LNs. 81-84

6. Modified Head Section for the Experimental Combustion

Chamber CC-12

7. Details of the Modified Head for the CC-12 Combustion

Chamber used in runs nos. 1-72-12B

8. Schematic Diagram of the Flow System at the Engineering

Experiment Station. Used for the Chamber Tests

9. Safety Trip-Out System Incorporated in the Combustion

Chamber Flow System at the Engineering Experiment Station

10. Plan View of CC-12 Combustion Chamber as Modified for Test

Runs Nos. 1-5-12B.

11. CC-12 Combustion Chamber Showing Thermocouple Location

12. Fuel Injector as Modified for Test Run #8-12B

CONF IDEN TIAL

C 0 N F D DEN T T A L

TABLE- 0' C t

iRUn#l.1B )92-BModel- 1.2BF

114. Baffle Evaluated as a Control for the Oxidant Gas StreamUsed in Test Runs #23 - 241-2B

15i. Baffle Evaliated as a control. for th* Oxidant Gas StreamModel #l2B2B Used in Test Run #25-12B

16. Baffle Evaluated as a Control for the Oxidant Gas Streamand as a Possible Flame Hol.der Model 12B2C Used in

* Test Run #26-12Bl

17. Becco Designed "Donutt" Baffle as Mounted on the Fuel NozzleModel #l2BE Used in Test Runs #27 and 29-12B

18. The Donut Baffle Incorporating Various Modifications Usedin Test Runs #30-45-12B

19. Arde Associates Designed Diial Swirl Turbulence Inducer RaffleUsed in Test Run #146-12B

20. Donut Baffle as Redesigned ani Bilt, with 1/h"f Throat to BaffleClearance Used in Test Run #48-53-12B

21. Donut Baffle as Modified for Test Runs #54-56, 58-66-12B

22. Modified CC-12 Combustion Chamber Incorporating a Water SprayRing at the Uncooled Liner Packing Section,

23. Becco Designed Umbrella type Single Diluent Wa-ter Nozzle asMounted in the CC-12 Chamber for Test Runs #53-64-12B.

214. Donut Baffle as Modified by the Addition of Slots Through the

Baffle Spacer Ring Used in Test Runs #67-l2B, 71 and 72-12B.

25. Donut Baffle as Modified and Mounted for Test Runs #68 and 69-12B

26. Combustion Chamber Configuration Used in Test at Becco2-1/2"1 r x 4-5,, long combustion zone

27. Flow System Used in Combustion Chamber Tests at Becco

28. Becco Combustion Tests Flat Flame Holder Through RestrictedEntry head Insert

29. Becco Combustion Tests Conical Flame Holder Thr-oughRestricted Entry Head Insert

C 0 N F I D E N T I A L------------------------- -- -- -- -- - -

C ABL F COEN T (cotd.

Figures

1' 30. Bec obsin et 1m oder, Straight ThroughHead

31. Reverse Flow Test Assembly Used in Tests atBecco

32. Apparatus Used to Study the Flow Characteristics in atTransparent Model Combustion Chamber Using High SpeedPhotograph

--------------------------------------------

C 0 N F I D E N T I A L

ABSTRACT-

A 10,000 shaft horsepower submarine propulsion system utilizing a closed, steam

generation cycle with turbine - reduction gear drive was assembled and operated at

the U.S.N. Engineering Experiment Station, Annapolis, Maryland, from 1946 to 1954.

The system was designated the Alton cycle. The propulsion unit utilized the

combustion of diesel fuel and decomposed 90% hydrogen peroxide. Exhaust gas from

the water cooled combustion chi:imber war desuperheated to provide turbine steam inlet

conditions of 750 psig and 1300OF nt full power. The cooling and desuperheat water

supply was furnished by the turbine condenser. The Alton cycle represented an improved

version of an H202-diesel fuel propulsion system rated at 2500 shaft horsepower

developed by Germany during World War II.

When the Alton project was teiinated on 1 March 1954, the only major component of

the system requiring further development was the combustion chamber. The first Alton

combustion chamber failed because of burning of the water cooled chamber liner which

was in contact with th-i intense combustion. Modifications of the liner, fuel nozzle,

and liner cooling water system were unsuccessful in preventing liner burnout particularly

at extended full-power operation.

Becco Chemical Division of Food Machinery and Chemical Corporation was awarded a

contract on 1 May 1954 to analyze the failure of the Alton cycle combustion chamber and

to recommend steps to prevent burnout. On 1 July 1954, a research project commenced

at the Engineering Experiment Station to develop a reliable chamber for the Alton

system. The development program was sponsored jointly by the Bureau of Ships Research

and Development Section and the Office of Naval Rebearch. Becco's contract was amended

to provide ei,;ineering consul rig services during the duration of the program.

CONF TDENT IAL

C ONF IDENTIAL

The actual-test work under the new program was startel in January 1955,,utilizing

a combustion chamber liner design and-liner instnmentation previous9ly- proposed by

Becco,. Fuel nozzle., decomposition pas inlet turbulence devices, and combustion gas

cooling water spray modifications were made with varying degrees of success during 71

development test runs. A firal design evolved which gave successful operation for

2-1/2 hours of continuous rinning at near full power in the final run, #72-12B. It is

Becco's opinion that the chamber configuration employed in run 72-12B could successfully

meet the requirement of full power operation for 10 hours, The program was terminated

on 31 June 1956.

A brief decomposed H20O2 - diesel fuel combastion study was conducted at i3eocc in

May and June of 1956 with a smnll combustion chamber. The progran evaluated 8 fuel

injection or liner modifications that had not been evaluated during tests of the Alton

system.

On the basis of the test program at EES and Beccop recommendations are made for

further improvement of the similicity of design and reliability of the combustion

chamber configuration which operated successfully In run 72-12B. -One of the

recommendations is based on an analytical description of the Alton chamber combustion

reaction prepared by Becco consultants. The development of the analytical description

and the close degree of correlation between the analytical predictions and test

results is summarized.

Additional recommendations are given for further test work to help form the basis

of future HeOg supported combustion chamber design. A possible method of more

economical testing of combustion chambers is proposed.

C 0N F I D E N r I A L

COMPYDF, TTAL

Thrinfg World Urnar II a r-i ,-en 'vting trbine system utilizing _high strength

ehydrogn peroxide, fuel, and I.r w 0ns dcveoped by Oermnny for scibmarine propul-

sion. ty the end of the hosti 1 i.ties, any -.. m trials tith the submarines had

been conducted, but the croft ';ad no, ranched the operational stage of develop-

ment. A complete propulsion system -as brought to this country in 19L5. Tests

conducted at the Eninerring Rkxeriment ftation, Annapolis, Md., Twith the

German equipment proved that ! - i,:.ntion of high strength H20 2 )nd fuel

for submarine propulsion was f,.isib].e The Germn system utili7ed 83 per cent

11202 (17 per cent by T,.eipht .,v nr) and synthetic Diesel fuel. At. n chamber

pressure of 500 psig 2500 shaft lhorreno.er could be developed with the steam

turbine- reduction eer. arrnnenent.

Startinr- in 1oi, a nm, nronulsicn system similar to the Germsn plant

was built by Allis-Chalmers 14fF. Corn. nnd was designated the Alton Cycle. It

tans instnlled in a submnrine in][1 mock-up. The Alton Cycle vas oripinallydesijrned to aroduce a mximin cf 7500 shft J at 750 psig chamber pressure and

1300GF combustion chamber discbfrpe temperature. Early in the test program

the output power rnting was increased to 10,000 shaft HP at the same exhaust tempera-

ture ano chnmber pressure. Full power operation was to be sustained for 10 hours.

The combustion chnmber (Figure 1) was fed -.ith decomposition products of 90% H 2s0,

Diesel fuel, and water. The P'0 wns first decomposed il'.a catalyst chamber into

steam and oxygen at 13600F. Fuel i.as injected into the decomposition gases as

they entered the combinstion ch,.mber. Trnition of the Diesel fuel occurred without

the help of an irniter because of the high temperature of the decomposition gases.

The diluent -'ter ,.,hich circulted throurh the catplyst and combustion chamber

cooling passnrns r;s sprayed itto the cem1 "stion gases just above the combustion

C O ' F T D E T T TI AT,

-1-

I." C T E NT T~ T A L

cha-mbe(r cutlrt to rterluco the 'awtomntueto 1300"F.

* fln 1 ' Thrch Ic'! thle or. 'ertnery'. the Alt,-n Cvcle w-7s -termnatedo

* At ther tinc of toktr~int he ':,nly ro-pnnent of the system that refcuired

fuirtber testinf , th- co-Thvr-t.on ch,',bt-r. CNerntirn rit 750 psirr cha'mber

pressure resulted in ccmiistM-~ li~.>rTntir bvrnin;7 Efforts to prEnveft

l-iner damnrej incrensed cooliro- i.,ater vechcityl, thinner liner 1wal1s more heat

resistent rnater-LP1 for liner lniizr,1rr-er liner diimeter nt the com-

bustion -none, swirl impartE-dl 'o -!c "w pray, elimination of helical fine

or other ruide fins in the cocLsnr jrcr, nnrl the lise of Solaranic coating for

the inner linpr et'rfaoe. Twere . ;uicces7sful

As n result of a conferencei- on 7 ay 1Q1L a!t OTWaIshington, De C.,

Becco submittod P, rrorosil tz (17 t,, n~r~c complete rtrdy of th e Allis-

Chnlners chnnmber failure ind -. r .en6 stcrs to p'revent 'burnouts. The

oontr:'ct a*':cito ! zccc on 41-n n-'I- c~terrnspl --,s desic-npted Nonr

11P.7(00). Orn 1 July'I lc-lI, r.ero -rrnc;j(t sron-sored jointly by PuShips

Pesearch -ncl "revelopoment rer - t!he Office of Navarl Resenrch, Pover Branch,

corinonceO at the T'. S. Navarl T-;.ner.r1-nr 7Emeriment Station, Annvpcelis. Md., (E..).

to develop a reliable comhust.,n c'h-,'bc-r fr the Alton Cycle. Becco's basic con-

traict 7-',s Prpnded to rrovide cunsultinf- services duirinr the total time of the

project at E.E.S. 7,hich termin ;tcd or, I Jutly 1956.

Thir rrncrt will, in riart- . n'ri7e the informntion r'resented in P3ecco

Report ITR-1 titled, "Prolimiinary An~~sof Thirnout Failures of the Alton Cycle

Combustion Chnnmber CC-l2", is~tu'!d in Jlr 1055.

In acdtethe reocrt T--7 11 -nmit e a description of the test systemq Ind

the results of the runs maele i-- E.B.S. The inform,,ton --ill nsrillel the report

prepared 1-y E.E.S., but is nrr .- rrnted 'ere to act as a banck!-round for the mclifica-

(I ('11T 77 T r r Ty T T tN I

C ,,; F "DENT TA L

tions advoated by Becco and ""[S ,he r-!-rz'u" of a short H"0O-Dies&l fue±

combution study nnd,;:,ted lae "te :.nact period at Decco and final recommendations

for the combustion system :,. ,,:.,,,u ,': occ .,nCluded.

II. ALTON CHAMBER ANALYSIS A:" 1. DZ:TF:.......ED

Based on exoerience .... .c< ,- testing at EES from 1L8 to 1950 a

prototype combustion chamber ae3 . cx: a ,s 0C0. was dn igned in 1050 to be fabricated

from 3L7 stainless steel. (Fig. I) Th. CC-12 chamber comnleted a total of about 10 hours

of successful operation in bunkl? tcets : f i:-ort diirtion duiring 105 and l02. In 1953

the chamber was onerated a tota. ur -mnty 23 hours during 62 test -rns in the

submarine hull mock up. In the .,tnr f rie of tests the general trend was increased

power develop-ent for successivc runs. Runs "9 thru 62 were made at 735 psig turbine

inlet presiue ciich is dpprox.Lfr, ieull -. , r. th , . r.n. which was

scheduled J or 10 hours at full c;,.er. the exha-st temperature and pressure began to

decrease after 3 hours * nd 7 min:.es on ze-t. The unit was secured. Examination of the

chamber liner revealed numerous ,:s a.1 seve-re burning in the conical head section and

approximately 1/641" of scale ori .he wae: ido of the liner.

The chamber was renairec, .d mePin.... by replacing the 347 stainless steel conical

section of the liner with a ceraric-coated -20 staiLnless steel section of the same

dimensions. The ceramic-coatei 7 -20 st.a~ness steel was expected to be more heat

resistant. The conical head of the liner buned out iifter a few minutes of operation at

700 psig in run Nc. 65.

The liner was then made wi3h 1 nicklie wires to control the coolant flo:

pattern over the head section. The ..at.. - s e clenrance between the head and jacket

was red.ced to 1/8.. (Figure 2),. Thiner showed signs of burnout after 5 minutes oper-

ation in rur, & wrbe was m,....,,2a Kr, tfa inlet rresureo.

T

AV OO'. I

C "N T D E N T I t L

A new a, .2 n<z- wi 5 t ,. .. tn boes t ,nglc t- both the vertical

and ror zontii axs of the -, ecto n aF the m, irl pattern of the

decorros, , (Fi, r . ) ... t i'u r, PJ F 1. stain.es. steel in the head

sect:.'n ws ni,' :...d .C5c" r.. ... .. " O neration for 8 minutes at

720 psig in run 7-1 rOsulted , .--"e': :n:.r ng.

The next mrodifcaticn ic:n-. '.- ., -,, the liner wall T,h.:kness to an average

1,/8 of an inch. R',ns ,2 thn, " . :a--.-:- n "3t .50 nig were suz'e3sfu.. Three hours

operation at 650 psig In rn 7. : t.: burrout.

A new chamber was evala 'n -.. L , P.- (Figire 4). The lower diameter of the

con... .ton was increa.- r., - ,i" ths ,endin to gi. the linera bell shate. The cne angle , ';,si--itl -.r ,, der, The coolng water

pass ~~~~~-er ninth cooin wat.,ehrk,: ",:r ,,''

passace r., th and liner thickne-a it .-ras hoped that the flame would

maintain :zs~q previous dimensaC.- & ~ ~ Sace. of. no combustion next to the walls at

the turn ,' the belied section, ;at . r's ;u and 80 at -50 and 60C p3i. of

metal flow wTas found in the head sac'

The EES coombusi.ior charbs: CC. .- ,;a.3 then installed. (Figure 5) Liner naterial was

25-20 stainless steel, 7/61" th:h&a , imb-r pressure was increased during runs 81-53.

Run 84 was made at 600 psig for 7 .te. -,ner inspection after the run disclosed that

the liner had :- llarsed inward : l.. ir a-.t cf the straight section. No burning

at the 'r--. ......... ed The . test.: tcsP nrogram was termir-+ed with ran 8L4.

At the outset e. cr.rlt w;r ;i heat transfer anal',sis of the Alton combustior

chamber (1) using data from ran Ti T-b'e 7 wa, nerformred and Becco submitted a modified ane

completely ins i trented (ther"ci7 - s.- nressure t.ape) liner design (Figures 6 & 7).

fAlten Cycl Cc7n1M,. . n Chap..er CC-12"'..hnic,' Rert NR-. Be " Ccmia D iv.,ion, Jnnua .ry .9'5

F F E N L

Best Available Copy

C C U: D,: E 1: T T A L

A prehmunor- he,,t transfer -, ;: , ton charim -vr as presented by Becco at a

conference held on 19 July T' S. P ,nor .est!r. drawings were sent to EES

in Aulust '.. The princip2eo " r.i-1-, the proposed liner design were as follows:

a A flat t.yne head ':- : .- ded to redice the gns velocity in the zone where

"ur-.. occ'..rre '......... - ., This reduced velocity would decrease the

,,eat trqnsfer fil r -r, ine side of t). liner and consequently

reduce the tenper. . . r: of th.e lirer.

h. The cross-sectiona _ -r; t: cooin ,rter annulus r. the heed section- " . - as des, d t aow ga

-;Ps increased fro- c,.± . ~ ~:c 't~a ~-'~

!-bhles formed by b- -... *.e.-. -,..t heir:g trnpred end ciu!ing a hot

snot. The elimint.<.-, 3f cs wb, vns deemed more important than the

hither water veloc L, nL.., rithI-he 1 /R1, dimension.

... e - c o ..... - -. d .1. thus pr-viding .. ore

heat transfer arec -- i h , or '.ater velocity beyond the are9 where most severe

bu-in, occurred wit the A7.'on 1cc!' liners. Continuing the helical coolingfins to the throat " ..l ,rrc. s- becn found to be unsatisfacto~r.

An extensive therrmcco~tnl r- on the outer surface of the inner liner was

proposed in order that the affe:.ts of the 'uel nozzle and liner design variables could be

obtained ouantitatively and wit:i q mun-.nc of testing. It was honed that the tests withthe ins- -n. d ine " wci sL-e as a guide ir: -eri-- which design change would

be best in carrying on a succesn<-fv.1 test program. The reconr-ended liner design and

thermocoupie installation werp 2ncor,-d... in the combustion chanber development

progra:.

A-ditlenal recomrendati m for The -rogran wer: included in report NR-I. The use

of nokle 'Ilk" cr Rosslyn retal c rtainless steel for liner fabrication would

de.r..... thc tnqr tleerat r . -'-d thrEK tle incresed thermal conductivity

Best Available Copy

C 0 N F ID E N T T A L.

of. the nickle "Al and Rosslyn',iftal. Elimination of scale on the water 'side of the

liner was considered to b6 ori tA tIro mos i important factors in successful operation of

the chamber. The continued une. of a closed wnter system was sugrnested in order to

reduce the scale buildup. The angle of fuel injection could be investigated. to, reduce

the direct impigment of burning fuel on the liner walls. The effect of inlet oxidant gas

"wirl might also be evaluated.

The recommendations given in report NR-l were based, in part, on the advice

solicited from individuals outside, of Becco who were experienced in the field of high

energy release combustion sy, te-s and in. transfer.

These individuals were cntacted during the period July 1954 - January 1955.

Additional information was gaine'd by Mr. Ralph Bloom, Jr., of Becco, on a trip to

the United Kingdom in January of 195(2 Thus the background for consulting services

that Becco had gained through previous test work at Becco was augmented by several

sources#

III. TEST SYSTEM AT EES

The test system employed at EES for the combustion chamber tests is presented

schematically in Figure 8. Tho system was installed in a test bunker at one end of the

building. A reinforced concrete wall separated the system from the operating station.

The instrumentation that was incorporated is given in Table II.

The complete H202 flow System was as follows:

a. HkO2 was pumped from 30,000 gallon storage tanks to a small "day tank" which

had sufficient capacity for approximately one hour of chamber operation. The large

storage tanks and day tank were located in a separate building and are not shown on the

schematic diagram of the system.. .

(2) British Submarine Plant CnLustion Chamber and Other Hydrogen Peroxide Developments

Report of Visit to GreatBrtain, 31 Janary- 16 February, 1955,

9 0 N F T D E N T I A L

6-

,

b. From the day t;;nk thoIT- flowed down through a degassing-pot to the H-N

booster pump. The degAssing Tn t. removed anyr gps entrained in the HO,,.

co After passing throuvir a propo~rti.oning device the H- reached he aucotion side

of the triple foed pump. The triple reed pump consisted of three positive displacement

pumps, one for each of the system flida driven by a single motor throug h speed Increa sers 'M

The pump raised the liquid preisure from the 30-40 psig discharge pressure of-the booster

pumps to about 200 psig above combustion chamber pressure. The flow of H20 2 through_ the

proportioning device controlled the flow r ntes of the coo2.ing water and fuel in preset

ratios.*

d. From the triple feed pump discharge the Hc-Op passed through a two way ir-

operated pressure valve. Actuation of the valve by-passed the 110O2 flow back to the

degassing pot.

a. Normally the HpO2 passed through the two-way'valve to a throttle valve which

was operated from, the main cont.-ol panel located outside the bunketo

f. Next the H20a reached a cam stop valve. The cam valve was also manipulated A

from the main ,control panel. The hand wheel1 had [4 positions: off; No. 1, HP,02 only;

No. 2p HnO2 and cooling water; No. 3. H 22. water and fuel.

' go After passing through the cam stop valve the H20z- entered the catalyst chamber.

The water system was a closed loop with the followin'g flow sequence:. .*

a, The water booster pump took auction from a .feed tank located inside the

bunker., A strainer was installed in the line to help prevent scale build-WxpI

on .the combustion chamber liner. ,

b. The water booster pump discharged through a filter to the triple feed pimp .

auction.

C 0N F IDE NT I A L

C N F I D E N T I A L- -. - -,, -.

c. From the triple feed pump the water entered the p:'oportioning device where

the water flow rite was controlled in a ratio of- approximately 2 to 1 gpm

of H:. flow.-

d. Water flow from the proportioning device entered the cooling water passages

of the combustion chamber and catalyst chamber in that order.

e. Part of the water discharge from the catalyst chamber could be circulated

through a cooler and pumped back to the combustion chamber inlet to increase-,..

the flow of coolant through the cooling passages.

f. The heated coolihg water then passed through the cam operated valve-and

entered the water spray arrangement located inside and at the bottom of the

combustion chamber.

The fuel system followed a similar path from storage tank, booster pump, filter,

triple feed pump, proportioning device,, cam valve, and solenoid valve to the fuel nozzle

located at the top of the combustion chamber in the flow of decomposition gases.

The combustion chamber exhaust passed through the following units in order-

a. Steam separator - removed entrained liquiid or solid particles that would harm

the turbine of a complete propulsion system.

b. Orifice - simulated the pressure drop through the turbine. A

,c. Desuperheater- supplied the reduction in temperature of the turbine exhaust, A

d. Condenser - as in the Alton cycle.

e. Condensate pump.

f. Water feed tank.

During operation of the combustion system the excess water produced was

dumped"down a drain,

The test system incorporated a trip out circuit (Figure 9) both for safety of

operation and ease of shutdown. The entire system. could be secured by a manual switch

-- -

C 0ON F I E EN T T A LS.... ,

on the main control panel or would trip out automatically in the event of:

a. loss of control air pressure

b. loss of triple feed pump lube oil pressure

c. excess temperature or exhaust either in st~am separator or exhaust line loop,

When the trip out circit was opened either with the hand switch or because of

emergency conditions, a, b, or c Ahove, the triple feed pump and booster pumps were shut

off, a solenoid valve in the fue3l line to the combustion chamber stopped fuel flow and the

air operated H2 O2 by4-pass valve stopped the flow of HPO 2 to the catalyst chamber.

In addition, red wa'rning lights installed on the main control board flashed on in

the ever.. of

a, loss of lube oil pressure to triple feed pump

b. loss of control air pressure

c. loss of condenser vacuum

d. high temperature, triple feed pump lube oil

e. excess pressure in steam separator

f. loss of seawater pressure to uond.nser

g. high temperature, water to catalyst chamber cooling passages

h. high temperature, H,02 after throttle valve

1V.. PRELIMINARY TESTING

The installation of the test system at EES was completed in early January 1955.

The catalyst bed used during the later Alton runs was reactivated with samarium nitrate.

The bed consisted of 4 - 10 inch diameter silver spirals each 2-1/2 inches thick. The

first few preliminary runs at EES were operated with decomposition only; no fuel was

injected. The catalyst bed functioned as desired. On 24 January 1955 the first

combustion run was made at 300 psig combustion pressure employing a fuel nozzle that

had been used in the Alton runs (Fig. 3) and with a chamber configuration as indicated

CONFIDENTIAL

-9-

C h - - - -,

CONFIDENTITAL

by Figure '10. The run Was.designated 1-12B'o Inspection of the combustion chamber liner

after the run revealed that nn damage- had occurred due to overhenting of the metal. The

Teflon tips of the wall temperatore thermocouples were found to be, crushed by the

expansion of the liner during combustion. It was decided by EES and Becco to replace

the Teflon tipped thermocouple arrangement before the next r.n with wires peened into

shallow holes drilled in the outside of the liner. Thermocouple location and number

designation is given in Figure 11. -

The second run, 2-12B, was conducted on 3 February 1955. Chamber pressure was

raised to 450 psig. The thermocouple installation was found to be satisfactory although

the wall temnerAtures were lownr than recorded in run No. 1 and the; difference between

readings for thermocouples in the same plane was as much as 4000F. The insulating affect

of the Teflon tips accounted for the lower wall temperatures in run No. 2 but no

explanation could be advanced for the large difference between readings of thermocouples

'9 installed in the same plane. Each well temperature reading remained essentially constant

after a rapid rise when combustion was initiated.

Chamber pressure was increased for each of runs 3, 4, and 5-12B to 650 psig in rur

* 5-12B. Data summary for run No. 5-12B is given in Table III. The liner was removed

after run No. 5 for inspection. Metal flow was present in two areas about 120" apart

and approximately 2 inches below the beginning of the straight section. A red oxide

deposit was present in the dome, extendin!' about an inch below the beginning of the

straight section. This was followed by a black carbon deposit around the circumference

of the liner, about 1-1/2 inches wide. After inspection, the liner was cleaned of all

deposits.

The test procedure developed consisted of the following major steps:

a. booster pumps on

b. triple feed pump on, low speed

SC 0 N F T D E N T I A I,•- 1 0 - _

C 0 N F. I D2 E N T I A L

*c. Hgem throttle valve'opened part way

d& H202 cam valve opened - decomiposition stairted

es Combustion chamber pressurs from decomposition-increased to approximately

150 psig

f.- water'cam .valve op-ened briefly to check correct'operation of water systemn.

Water cam valve c0losed. (filuent water ilwindicated by rapid drop of exhaust

temperatuire.. This check was Made as a precaution against combustion without

cooling water which would res~lt In immediate severe damage to the combustion

chamber. The recirculitlon or witer through a heat exchanger was maintained

during. ata rtup',),

* g. water and fuel csmr valve opened almost sirmultaneously. Combustion initiated.

* h. visual. observation of the test sirst~m was made through peep holes in re-

inforced wall between operating station and combustion chamber. Instrument

operatiofl.checked.

i. booster'.p pumps and tripl e feed.-pump speeds increased until desired chamber

h., pressure attained. Average length of starting sequence approximately 2 min,

The water cooler could be by-passed if and when desfired.

5 A J. readings taken off non-recording instruments on signal.. Data points marked

Z., on recording..instruments'. Orsat analysis samples taken.

k, triple feed pump speed decreased until chamber pressure reached approximately

150 psig.

* 1. hand trip switch opened' - fuel flow stopped, triple feed pump off, booster

pumps off, system secured. Recording instruments off. (stopping sequence

duration 80 seconds).

CON F I D ENT T A L

m CONFIDENTIAL

m. HoOa lines from day tan' to combustion chanber drained if no further runs

were to be made thi same day.

During thel period that the first five runs were made,.Becco contracted

Professor Warren Rohsenow of MIT as a consultant on the test program. Professor

Roheenow had been associated with the program under consulting contract with EBB.

Arde Associates, an engineering consulting firm, in Newark, New Jersey was also

contracted at this time by Becco to mpke a preliminary analysis of the fuel spray

pattern for the fuel tips and chamber configu-ation utilized in runs 1-5-12B.(3 )

After run No. 5 Becco obtained thermocouple wires that were insulated and

bound together so that -a single hole theerocouple packing gland could be used, reducing

the time required to install the. thermocouples. A double hole packing gland had been

in use. After the thermocounle Wiret were peaned into the liner wall, installation of

the liner in the combustion chamber jncket was complicated by the need to pull the

thermocouple wires out throujh holes in the jacket and then thread the wires through

the two hole packing glands,

After run No. 5-12B the Becco representative at EES suggested a light and mirror"

arrangement that would permit inspection of 'the liner in place after the catalyst

chamber was removed. The method was employed in subsequent tests. The liner was

removed from the combustion chamber jacket only for repairs.

4

(3) Arde memorandum "Alton Combustion Chamber" March s 1955.,,., : , C 0 N F T D E N T T A L ;

- 12

_. C N T D E N T I A L

V. RESULTS OF TEST RUNS ANT) CONFERFAYCU TIMtD AT EMS DURING THE TEST PROGRAM

A. Conferences and Requ1Il.s of Test Runs #6-71-12B

A conference was held at E"S on 11 Varch 1955 to discuss the results of Runs

1-5-12B and to determine the procedure to follow in future'. test work. It was generally

accepted that the burning of the liner was due to liquid fuel hitting the walls and

burning there. The EES representatives pointod out that changing the position of the

fuel nozzle would not be a desirnble method of preventing liquid fuel from reaching the

walls. Tests with the Alton syitem had shown that the nozzleposition was critical;

either raising or lowering even slightly, adversely affected combustion efficiency. For

the ext teat runas it was decided to first double the number of holes in the fuel nozzle

to reduce the fuel droplet velocity. If the increased number of fuel holes would not

prevent burning, the H2O gas swirl vanes on the fuel inlet pipe were to be removed. As

a last step the gas swirl in the dischnrge from the catalyst chamber was to be eliminated.

- It was also agreed that Arde Associates would be contracted by Becco to mqke a complete

analytical analysis of the fuel injection and design a iew fuel nozzle to eliminate liquid

fuel from reaching the wall.

The test program was resumed with runs 6 and 7 employing a fuel tip with the

number of holes in the periphery of the nozzle increased from 12 to 24 and the diameter

of the holes increased from .O625 to .067 in. The chamber pressure for runs 6 and 7 was

650 paig .And time on fuel wa. 26 and 31 minutes respectively. Inspection of the liner

after run No. 6 revealed a red oxide deposit as noted for runs 1-5, extending from the

silver deposit on the inlet neck to about 1-1/2 inches down the straight section. There

was no evidence of metal burning, flow, or slag deposits. After run No. 7 the liner was 7

slightly pitted about 1/2 inch below the neck. A very slight evidence of metal flow

was observed approximately 2 inches down the straight section about 2 inches wide. Runs

C 0 N F ID E N T I A L

13 -

" ~- . . - .. '

,-C 0 W Y Ii D E N T I A L.- .':1 . -

CO, XD. : . , •

Runs 6 and 7-12B showed marked improvemunt over runs I thraugh 5^12B'(reduce 1iner,

temperatures with approximat.ly the same combustion efficiearcy) but .the evidaoe o*f

metal flow in run 7 indicated the need for further changes.

'Following run 7-12B the fuel nozzle was modified by adding 12 -'1/16,, die.

holes in the bottom of the noz-Lo parOl.lcl to the chamber axis (Figure 12) to further

reduce fuel 1bjection velocity. Run No. 8 at 610 - 670 psig chamber pressure for 24 min.

with'the 12 additional holes in the bo',tom of the nozzle resulted in more serious scale

formation and pitting at the top of the.lirner dome. Metal flow in small rivulets was

-present around the entire 'circurerence of the liner about '1-1/2 inches down the

straight, section. Run No. l0-12B was condunted with the number of holes in the bottom

of the fuel tip decreased to 4 es recommended in Beccos letter of 4 April 1955 to the

Director of, ES. No date was taken during run No..9 because diluent water pressure was

lost soon after the start of the run. A repeat run, No. 10, caused increase in the .metal

flow and pitting observed after r'a, 8-12B. The liner was cleaned of all deposits after

Runs 11 and 12-12B were run with all holes in the bottom of the nozzle plugged

except the central drain hole and the diameter of the 24 peripheral holes increased from

.067 to .070 inches. Run No. 11 was conducted at 610 psig chamber pressure. The

chamber pressure was increased to 650 psig during run No. 12; time on fuel for each

run was about 14 minutes. 'The Liner was inspected after ti.u- 12-12b and slight pitting

was found just below the inlet neck. Run 13 was made at Beeco's suggestion with

decomposition gases alone and indicated that the liner wall temperatures were highest

at the beginning of the straight section of the liner as noted for the previous

combustion runs. The run indicated that the liner burning problems were related to the

HqOR decomposition gas flow patterns in the chamber caused by the swirl vanes on the fuel

9 nozzle.G. O N F I D E N T IA L

--Q -

TI

S! t. I. vZ'rV ct :

At 61 ( psi -a were near- those8 cb-scc< for r',.7rs 6 pilt7 the 00ombu sti1on) p:rssr tto wans ri,- Ied

to 72psig (maximum design op,!srat.'on pressure) u rnin un 165 and 171-12B, The Inside of

the zombustIon liner was innectcd- after each r. n tind n o burning was noted .~ WllI temp.-

- r, Lure reflrinrs w(-r) BIS oC '' n~n~r thaIn A t>v~Ugr

-ut sti'l higher0

[Rukn 18-12-,B was condwuct tn-i I%]L. nn bo:nit lof asn snvirl vanr.: cim the iThat

inlet ,.and 8 ue nozzle dei~ o. ~ vth l-t of ruans Cand T-123 (2K- - .06*1 holes[r u r'ipherj plus 1/161' K.iam, iiIle). ' r L o )f. -bcfuel vies attn laid but thec comhbuation

K ~ ~ V1 was .r, with Great ua >.t.YQvorslu5 Approxnna"tocwt for all

urt'V JOLU5 TIfIS Th th e neU [o aC1 c1 "'oratio7 suh as the il vanes to p.rovide

. tuiiuontmixing of 'Jdecaiposisia.s -,msc s -. 1 7 fywscery .. ~~-.

Run No. 19-12B demonstro--tod.: th reslt of rns U and <11 with

_ Lc-BE (Eigpre 135) z;oV ,d haror.o n' o ron had- ocrela*:r'lt of n *.

±IB.'.28B. No data was taken during runs 20 and 2' tjocaiise of mnaiunrction of' the .,Ipropor~-

[oning devi1ce. Run, No. 22-312B3 with flozZ,,c 12-31F was inaae to check out the rpaira-d

"rOpo)rtiorin', 1evice ond to 5C:1j''1*r~'?ULJ. i)2?exctcnded 4.,[ T ±e on fue r this run 22 cni-' T;im~i's i- oy prerioun; run w-1ihnzl 2-

vi 26 T.I. WO sco. in inr 16-211. i eeue the L-iner vtil edn'.nt above those

I, -

21(1 S. r&.t,--rin o '

Y 'DI F 1 N'I

* A

C,% r)

J1 T!. . I -f,* tho

15 Wfi~f!i~~ 10 ~ .-9~ C~ tli 1 4a tAm w-1 an- (> oe he jareC

no~L ith gas swtirl, novd (rTun IA-1.201) TIir liner was excnminod. and f ound to 1be inA

3t I 3fto)r condition.

A se.cond c ftrnevi h:I i.. I' ' ''Mylt P~de~ te. t rst r.emlts

i t tlit3 o f thej an 3 1 -,r 'nvn o ~aVn of ~ 1t t, mor. f1r eV-i2 and coment.I

F Ther v - V- Yid .n- -sC 'ht ft

ccsrebydr-,plet ptcntral. Lc~r ±4 t Tre T APt 1!k) ITIOS b deriornrient on chamlber

fl'issiS'z The toraUei nil- .fbr rlro plet s:LZ(' ca1c',iatons vs qetire but it'was!

thst ,~ otter fcynwi I. e m!n av,i!g W~l Tho a Cfnrt of the fe rrtsi l

j ai,~~ ua a dti u~qci6 thr-e.foldoi *. was acepe ot was1

lo ie ta 1~~totImof' fi'i tore thiat . ffr:)lnrlf nicrh: -..T ffiin

to :on',TUnus tven -if vuch ar n.'statcr wv)i'rLJ elii.ato) the roshfV of A 10-hour JA

r,.)n wYiA.rhr the H.:%, that vus1 01n howLnd (The nror'ranm won started with a L.1nited amount of*

r r nd no funds wore rTrovirled t~o purchasei mre-) It was further n[,r~ed that additional

:3wu.y of folinlet velocity (cv njlro tir hoit, 3 / itot ;zat oos

f ter tiirovmrnent5 M)1?ront.Iy 'ri" 1)x_ f" to' r,'rn Iitbe'cer I tidi t? e:ThCrjiM'f1t..l

qrtL9.Tncreasl n g the fiel. 'tin Unit a f rom .006. to .070 inchies! ii limAur had

rti~iltaiIn onl~fsight chaEnge -s in, blid ( c-ton'orOanig Wr Ut

~Q ., q~- to to dirct-A twa F, t, t.. 'rom nt. ofst i. o 5Xf 8 I'rr; '

iK. V fit ;:t'iiI v 2tCS2 ~ ''IIU'H\'.;-, at ihd'V to the

.0~ A9 L\.,,

e v s to i i u ate et .'e:' u1 .. oU.H ',c.xa

Run 2) - 28B mna on jcr.,to a o, ;yf 3i t(5~'1"f'ile

d,bsin s a s n ,1o1212A vihzIiinU2' L"~: 17u !Ai f/vsr In ano 22oir

tho 1u"fl inlEit 1Ape Aver,,go nnee. The results were diLscc'rvagUg 0ti''re wOrn nly a almtte

An as1 P,13 3 *The readiers;'aP, Tu1 w eda o0 th LEfr ~s

ter.,::ek a--rid the dome. Th). T. rA-r, .'' r E! tt soe c-,d! 1\,(r et 2sb d 4

-. After the Iiiner wai .r--t-,aind .rtn 2 < 2 'wle lt a small eca;JaxI olbaf fle

vith titurbuilence ring added- to the ba~x edo te ffle. Th'e --swirl vanns on' theI

vrA er#. removed. (FI4gure 1 -. C'nm, et rll- 5 n t 1 .. f td aJY "C- "

i ier 1-,baffle damnage -occurrod,

F:ran 26&-i2B a l/8)" ivi Yti cr'r. 'vI F, Vld Ft:o tlhe 'A' etc iiF.:i1)

Thec' t .~sbrned off and combt nr, vis 3:zt 'atr 0 a7%

Run 47i-125 evaluateda a' flecef opAdtru~c onut wlrel ded to the

V eI nozzle which was positioned Lc it.iuce tefuel sr a I '.

3rt C.17 In runs lh1 through0- 17-1213 a nd 1 9 Uhrou 1,1i'h -I2 B (Fiara#3 17) The r-un wea

rti t 60C psi g chamber prenar,!-i forv 11' n-11tio11 f ri. I? -ie. Con wra5 8,65 wall -2

towperiture readings wore) low vi 32t oI le <fe !,I.-:l;t 'F?%Lar3 The'ru

-712B wva-s cons-idered more enfm-pn:thi. C' ~O731 ~stu. Tr; f- v- -er 1 .a des igned

tc reat?- fuel1 and oxidant aix 4 f iI;e i:I tCi!0211Ci' .2::*'Le

cs~tr ofthe iarrber

C , F- D N T TA L.' , .

W ith the .fel nozzle confiur. itin z, rune- 1.1 and 12-.12B. 'Phe resulting wall

temperatures and C02 were similar t.(,. th,: d 1 6e of ruun YL ird 1 . A hole was burned in

the doae of the liner.

A third conference, was held at I1BS on 7 Ju)y 1955o Runs 24-12B'through

2-12B were reviewed. The burning of the lower end of the liner where it is backed

with packing in run 24-12B was attrilhu'ted to cont.nat with burning droplets of molten

metal from the baffle and the liner neck. It was felt that the hole burned in the

liner dome in run 28 resulted from tlicwo dnc.,easfd cooling water iassape width at the

dome which was caused by the repair of iner damnge from run 21L-12B. The conference

discussEd thl r'ad for a new liner, because tho EES engineers felt the liner in use

..was near the end of its life. Beoco had ben In contact w:i.th the Youngstown Welding

and Engineering Corporation of Youngsto)Nm, Otio. concerning the fabrication of a liner

from Rosslyn metal. The contact resulted from Becc's search for a material suitable

for liner. fabrication .nd which had ; _-tater heat .transfer coefficient than stainless

steel. The price of the Rosslyn rntqpl 1injer, wes approximately twi.ce the cost of

fabrication of a 25-20 stainless Fteei Iner from stock that was on hand at EES. It

was resolved tu make a new liner out o the 2,-2O stainless steel for economy reasons.

The ONR representatives pointed out that the entire Alton propulsion unit

would be held in reserve until such lime a8 it might be needed in the case of serious

national emergency. 'The need for , f '5 hour, full load, continuous test run

f was also stressed.

Arde Associates presented a c.ounter swrl fPil nozzle Jacket design that was

Sccepted for fabrication and test. it w-i , cided tat the nexte t

SwlVn'' turbulence rings added to the. IPi'"., . t);at h.wd given .oc results in run

- ' - 11 . TVes % rbulence,

2:,' ,7-1.2B after the results of i ,.,v c *wr ,e relvod,,t u

0.,14 FI IVT I L

tq

00- ON-F 1DT EN T I A Ld- ,!;

U ringst were to increase mixing and thus- Tftfpr65Va ~~1~~if efficiency. It was hoped

an opt-imum design would be indic nted. .

Run 29-12B on 22 July 19,1' : demonstraited the reproducibility of run 27-12B.

Ingeneral, runs 30 through 45-12B, evalunt; d the acid Itiori of turbulence rings ofIIP

increasing thickness to the ball baffla.(Figure 18). The affects of closing the 1/16",

drain hole in the center line of the .07,2'-1( and thO idditton of two holes in the bottom

of the tip plus the drain hole were also determined. One other slight modification

evaluated during runs 43 through L~i-12B (Fi'gure 18). During the series of tests 29

through 45-12B.9 which were completed on Octobear 12, 1955p difficulties were encountered

both with the catalyst bed and the proportioning device. No light off was attempted

during runs 36, 38, 39, and 41l-12B because of excessive pressure drop across the

catalyst bed. The bed was changed for ruan .37 and activated f or. ra-n 39,:40, and 42-12B.

Some of the successful runs had to be re-run because of oxidant rich operation due to

* malfunction of the proportioning device.

Runs 29 to 45-12B yielded the following results:-

(a) The optimum arrangement of' ba'A-1 baffle ai~d -turbulence ring occurred when

the gap between the liner throst and turbulence ring 'was 1/4 in. With

the 1/40 gap the CO-2 was 92-93%.

(b) Plugging the fuel tip drai~n nole reduced perf ormarnce

(c) Addition of 2 1/1611 diame'.ter holes to the bottom of the fuel tip reduced

performanice.

(d) Increasing the spray angle of the fueil slightly by cutting back the

bottom of the ball baffle (run~s h-.l2)did not affect performance.

(e) No liner burning or fliel tip melting occurred.

Ru~n 46-12B on 13 October 19 '; evaiated tthp ArdO dual swirl nozzle (Fig. 1.9).

Performncne was fair with 91.8% CO-_ but 4.he- lower end of the nozzle sa burned.

C 0 ,;F TD 1 . T T A L

A-

0. N ' .O F [1DEN T IA I.

.-The next series of testsq ruris bBf th rough 0i53-12B were made with a 3" ,diameter4 n bffle; that 'gave atfrt!aih leer-,n(.e between the rincg and the liner bhroate

(P iTe 20) Additional modifications made toc the 3"1 ring hnffle during the runs are

indicate6d 6n1 iigure 20. Runs 48.-53-12B which were completed on 7 November 1955 gave

r e'su that were inferior to the optimum arrnngement of small ring baffle and

tu rbd ,ten~ce ring.

I Y During the fourth conference held on 8 November 1955 at EES it was agreed

athat Sk uccessful 5 hour run could be made with the small ring baffle plus turbulence

ring.- Thie 5 hour run would have to wait until the new liner was completed. In view

of the poor results of runs 48 through 5,3-12B it was decided to machine a rihg .baf fle

wvith- the same shape and dimensions as the baffle with added turbulence ring that had

given the best results and to check the reproducibility of those results.*

Runs. 54. through 56-12B were made in accordance with the decisions of the

8 November conference. The fuel nozzle employed Is shown in (Figure 21). Guide vanes

were .installed on the fuel inlet pipe in runs 54 and 55-12B. Run 51-2B at 650 psig

ohamber pressure was without incident; CO2 was 91,,6%. The new liner (EES designation-

No, 14) which was designed by Arde AssociateSe ()was installed for run No. 55-12B. The

change's made to the previous design were as follows:

(a.) reduction of wall thickness' to 1/8"1 (from 3/1611 in the present liner')

Mb reduction of fin height tm 3/811 (from 51/11 in the present liner)

(c) increase in liner I.D. to 10-3/81" to incorporate (a) and (b) above and

maintain the transverse dimension of -the previous liner, 11-3/8"1.

(1"Modified CC12 Liner Design",9 Arde A rLt,it.port No. 455~3-1 26 July 1955

L 0'NV7 TDZ:Tj IAT

0 C N 1' II D' V.'P A .I4

-- ru 1B' at 645 priig for 6 8. t'UmiLn oy'eu red at the lower end

LI. 1Izle r wliero i t i.~backed with' pickug, 'Tie~ )'rrned a rc 1a wa q diroectly below the

-;i~7 I,(!p elbow. The fuel injoctoci 1 ',!,r mh1y -lund io be tilted slightly towa nd

To 1iuvnv~d iirca. aiide lutgs were a'dded t., ho blli1 h.-ffie for rn'5 6-l2B in an attempt

~. W. ih.rigofthe fuel InJector. In r,ri 56-128 on 11 January 1955, which was

cniitd at 650 psig chamber pressure for 6 miii. r) snc., addttiofnll Trning of the

k L-At-c'Y A 'Qie liner oucurred in two -deo ire ctly above diluont spray nozzles.

A: fith meeting wasi hold at EES -ii 1a~~r 9j, 195c). to discuss the 'liner

d~nae aused by runs 5r: and 56-1l2B. B-~- ~'n dtwo methods of' providing more

y_:,stive coolin .) about the -n)r ~ *f the linei- at its lower edge. One

ffluthc-d was to add a cooling water ring j.uqiL abovto the critical .43RtioT.. The ring would

be tnipplied by. four pipes one fron~ eadit o-1 thr. fnur diuent nozzles (Figure 22). The

appr~ionch would be to inistall a SiTmgdO Watr SnTry nozzle bo replace the four

Uiat had 'been in use (Figure 23). The !.ddit16n of a gas deflector ring to

.~' t gses away from the dead space pr~~ f'r liner expansion was also discusseidu., iT Ojlii of preventing burringo impro ir. -nts to theAddul irnozewe

a-jvcr.xed bncoe this nozzle was still beittved to be of' superior design. Steps for the

next :7ns wvere agreed to and were carried out in r'uns 57 through 62-12B,

Ru~n 57.-12B was made with a slightly imodified Arde dual swirl fuel nozzle.

Hlci c~cmbust~lon efficiency was obtaned, ,. COe, but srrAous birning in the dome

~ ~e ine c cured Fo n n 8 the fo o )I~l~ uel nozzle (Figure 21) was

K ±--nstaiLed and a gas deflector ring 72 n al juot abovc h diluentnzls h

Jjt.i ing was installed to prp)Veot wj: ri>. full from collectir., In

*l: :.'i~~'ceprvided for linor exn~~~Th H-i off almost comtetely

.i;gruns ' 9 and (@O- 12B thy 1IAW. 1v~'63 W O-Z1.e-9 WVr bffled

c c 2.~~D: Tr A 1,

C 0 N F T D E N T A L

in an aittearpL to proo±de complete i.ner wall coverage. DI ing uln 60-.12B ninor liner

burning near the diluent nozzles occurred. Tt was ai reed that the baffling of the 4

no, z.Z1es was not a satisfactory approach.

*For runs 61 and 62--12B the cooling water ring and It dilhent nozzle arrangement

was evaluated. Burning of the liner at its lower end was muccessfully prevented at

650 psig chamber pressure for a total run time of about 24 minutes. Data was obtained

in run 62-12B for liner wall and jacket temperature changes that had been noted

preiioualy in runs 56,6o, and 61 (Table TV). The temperature changes occurred rapidly

*after varying periods of operation while the system feeds9 pump pressures etc. remained

essentially zonstant. The liner wall and jacket readings remained ateady before and

a.fte the change. It appeared that the ro gion of most intense heat release siddenly

d-opped lower in the chamber because of some change in the character or geometry of

combustion independent of the external system. The change was marked by a decrease

in C02 Te phenomena was of concern because it was an Indication of unstable

! Ombustlon.

Runs 63 through 65--12B evaluatd the Becco "umbrella" diluent nozzle

(F.gre 23) one central nozzle replaced the .t nozzles used previously. The nozzle had

•r !:been lnsta.led lower than Becco had recommended. Minor liner burning at its lower e d

occurred during run 6h-12B. A deflector ring was added to the nozzle to depress its

spray for ran 65--12B. Severe liner damage resulted. The bottom of the liner was

completely melted around one half of its bottom circumference. The burning extended

!om the bottom of the liner up to a point corre:3ponding to the height of the packing

,baci.,ng the liner. The liner was removed f.r repairs. fle central nozzle idea was

aL rc-ned tecause the H,,02 ovailable for testing vas LImited and the addition of the

--Ing bad proved succeisful. Bocce felt t1::d, the central nozuze ,.. bc rnde

4.. . y Incredsing Its height ahov, thn bot,t~x .If the charter°

C0 1: F T . L

C0ON ; T DENT T A L

-he old liner that had been iised ear]y in the test, protgram was installed for

Piun '%-.1 2B and the !1 no-.,zle. cooling rlnr nrrann:;mon ws tested at 700 psig chamber

ptessure. No burning or liner wall temperahure shift occurred during 11 minutes of

operation. COg was 91.4%.

The percentage of CO2 in the non-condensibles of the exhaust gas decreased

from approximately 91% at 650 psig to 91% at 700 psig chamber pr,-zsure. It was decided

theat .more intense mixing of the decomposition gases and fuel spray was needed to keep

the CO? above the accepted minimim of QO% when full power operation at 750 psig chamber

pr'essure was attempted. Becco felt that additional turbulenc) would prevent the liner

*wall i w c. ,e " aes t' n had occurred previously. -".r to run 67-12B, ,-rcrlve

45" angle slots, each 3/32 of nn innh wide, were cut in the lower end of the donut

r i baffle in order to increase the turbulence (Figure 24).

Data was taken at 650 and 750 psir,. chamber pressure in run 67-128. The

percentage of COa of the non-condensibles of the exhaust gases was 94.O and 905

respectively. The slots in the fuel nozzle did not increase the CO2 but were successful

in pre-rent.ng the liner wall tomperature change. No liner burning occurred,

Four small swirl vanes were then added to the slotted ring bvffle in an

effort to improve mixing (Figure 25). The swirl vanes improved the combustion il run

68-12B. The CO was 95.9% at 650 psig chamber pressure, The same fuel nozzle was

evaluated in liner No. 4 in run 69-12D. "',o was 9 ao t 675 psig chamber" pressure

but s ight burning of the liner dome occurred. The swirl vaneR were reduced in width

for -mn 70-12B with liner No. 4. No burning occurr(ed in run 70 but there was little

performance increase over the slotted ball baffle without the swirl vanes.

After run 70 it was apparent that an extended run could he attemoted using

11 nc I~ o. th, slotted ball baffle fuel nozzle, and the Li nozzle., cooling ring.,

diluent water arrangement. The length of the final extended rin was reduced from 10 to

C 0 N F I D E N T I \ L

i C).NF IDENTI£hL

h1 5 hours and finally to 2-1/2 hours based on the amount, of HO; expended for the

development of a satisfctory combustion c;hamber configuration. ON'R's decision to go

ahead with the extended run was prompted by the Hj-1O that was on hand and slso by the

desire to complete the program by June 30, 1956. A brief check out run and the final

2-1/2 hour test are described in the next section.

B. Results of Test Runs 71 and 72-3.2B

Run No. 71-12B was conducted to verify the assumed trouble-free operation

of the combustion chamber configuration consisting of the slotted ball baffle fuel

nozzle, liner No. h, and the cooling ring, It nozzle diluent spray. The slotted ball

baffle fuel nozzle had not been evaluated in liner Nn. 4. The results of run 71-12B,

no liner buining or liner wall temperature changes, 9h5% C02 at 660 psig chamber

presbure, and stoichiometrlc fuel and H102 proportioning demonstrated that the long

run could be attempted. Data summary for run 71-128 is given in Table V0

It was decided by EES and Office of Nlival Research representatives that

the final run would not be made at full rted power with a combustion chamber pressure

of 750 psig. Instead, to help insure a successfal testthe flow rate was to be

limited so as to hold the chamber pressure at approximately 650 psig for a duration

of 2-1/2 hours.

The final run was made on 7 May 1956. Data summary is given in Tables V

and VI,. With reference to the data summary, the vari°'tn in chimber pressure readings

was due, in part, to an accumulation of foreign material found after the run in the

line to the Bourdon tube pressure gage and the continuous recorder. The Bourdon tube

pressure gage located on the main control panel showed decreasing chamber pressure

after completion of approximately half of the run because of the restrictions in the

line. The operators increased the flow rates when the false decrease in chnmber

pressure was noted, The chamber pressure also varied as 8 result of slight changes

CO ONF DEN T I A L

--L-

in the dihlei w'ter flow'to t~lho noz.zles (riot. shown I-y the water/11lno flow ratio). A

relatively small amun-t of cllient w.'tLr wa b.-pase ed during the f£iTr-t half of the

rur iii ordecr th't a high exhlaflst tenm-'eraturo coul~d bo.rnaiLntairled. Thre pyrometer[ giving the oxfoaust temperature Indicated occaslonal niirges. DurinL, the second half'

cof' the run1 , less diluent watenr was by- pissed thus roducing the exhAust temperAture

* and the Thssibility of plant trip-out diring exhaust temperature surges.;

Ths3 increase in CO tr;rother w-ith the rise in liner wall temperature readingep

jacket water temperature readingsq cooltr[. wakvr and. diluont, water temperatuire readings,

in the f irst 36 minuter.s of operation on fuLindicated that the data -of previous runs

taken nt short~r IrtervAlq sfter stairtup d~d rr4 roflect 'tho steady state operatio~n of'

the system. Some of the linorv anid jacket witer tEjmperatuare readings did not settle outIuntil 'atcr in t-he run. M~an- u f the li"ner temperatures were above values that had

boen observid ri previous runs whetn lner burning hid resulted. Inspectlon of the

S lizi'.,r aftpir nir, '72.-12B reveale.J that no h:arring had. occurred.~ In addition the fuel

noZZlIe W88 undamaged. The rur. was successful,

It was the opinion of the EES persone a nd th e Beccorpeettv h

had witn~essed the final run th~t the run would have been equally successful at It)Opi

chamber pressure. In run 67-12B which utilized the slotted bell baf'fle fuel nozzle,

the liner wcill temperatures r .;orded at 650 and then 750 ps g showed an average increase

(i' 240 ror the 750 psig operation. Par' -f the inc.rense is the normal rise for the

system.

VI. S-ammarv Discussion of' Coubistion Cha'mber Modifications - Project _"Hill"f

Chaning the design cf the head secb io~ of tecomuto chme inrfo

tf. :ionlcal shape utilized ciur-:ri, the~ Aiton projiect to thte dome shape reoommended by

B e~ 4iri r(t, eliminriae b'riiof u-hf. t~op portion of the lincir (Flities 1. and 7).

TheI ru~.*n~ in: w 4- trib cd to ~d ftrzl re-c c.g th, w anr Iv a and burin

CO 0 1I DE N T I A L

CQNVT-E N-TIA

4hee. ttepts to reduce thc fuol spray penetration by,reducing th f uel, injection

veac.ty gYa-ve Liproved o te ra t I It lis- mu f< ~~ll occurred. Tho fnel. injection

A wis l1ocreasod fro'm 7..' ft/s'mi. abot'.t20 ft/sec. -by inc'reaping the number

of ho1las in the fuel nozzle (F.iguTes 3 and 12). A 24 hole fuel nozzle giving a

con-Icni spr'ay patfern and an In srio velocity of 30 ft/sec. gave the beat e t

results. DecreaisIng the inciiided fue~l spray aigle also proved to be urnsucce.;sfi4 in.

pravrontInug liner burning.

The original combustrI,.( i nctrporag.ed an H20 2 decomposition gab sW.rl

:4 ut above th4 fuel tip. Data taken durin~g a test without combustion showed that the

4.location of the. hifhpest liner terneraLtires was the same for the non-conbustion and

combustion runs. 'The pas swir'. was cau3L-ng lncriised h-tat transfer by reducing h

thickness of' the gas film at thfe liner wall.. A combustion min with the gas swirl vanes

removed gave poor performiance U79.6% C02). The need'f 4'turbulence producing device

other thian tie gas swirl vanes was indicated.

"Coaia lff baffles, arrI IHdual swirl"' turbulence producers werl unsuccessful

(Figur~es IL , 15,. 16, 6nd 19). A ring baffle proposed by Becco (Figure 17) approached

the desired results. No liner burning ocuzred but the combustion efficiency.-was low

(CO2 - 89.6%)* Modifications -were made to the ring baffle to' give an optinum

performance of about 95% C0z (Figures 18s.20, and 21).

Hfigh performance of the ring or 11'onlit" baffle- risulted in chamber liner

bu= ing at its lower edge where it was hacked with-packing as indicated on Figure 10.

*wAI~lihgof the diluent spray nozzles was unsuccessful in preventing the damage to the

bottom of the liner. The add Ltion oil' a water sprayr ringr at the orit~cal section

provided a somexhat make-'shiff4 soiliiion. A centr~tl rozzle was partial'l evaluated

(Figure 23) but ruitur-f to 'th-) L~ nozzle -sprayv ring arranfget-ent wq ma de bacause of

limited 'projes~t fuind s.

* -0 N, ID.-. I N r I L

26.

C0 NF ID X NT IA L

'A linorwyoll tempo t) re fluctuation noted durilng the high performance

(95% 00) with the donut bafflp was eliminated by adding slots to the baffle (Figure 25).

The slotted donut. baffle turbu.Lence ring together ,-rthi the conical fuel spray and dilluent

irrangement of h nozzles and kbe cooling ring gave high peribrmance (average 97% CW~

f or a 2-1/2 hour run at 650 pgchamber pressure without any liner damage.

VIL Results of Combustion Tests Carried Out at Becco

DIn aceordance with cor. tract, amendment No. 6 dated 29 February 1956, a brief

H20,a-diesel fuel combustion study was conducted at Becco from the middle of May to

the end of June 2.956. The bssic combustion arrangement of HmO0, externally decomposed

and Iii -4 1 c~ fn. injer'Jon employed at ERS was retnined with a 2-1/2"1 T).

combustion chamber.

Flow rates of HriO2, fuel, and water to the 2-1/2"1 chamber were-based on a

combustion zone cr088-section area ration to the mnodified'Alton unit. Thus the heat

Srelease rate per in. of liner area was approximately equal- to that of the modified Alton

chamber. The combustion chambe r run at Becco had an effective combustion zone length

of abouit 4 and later 5 inches taking the distance from the throat of the head' to the

W point where the flame was qiienched by diluent water. The effective length of the

modified Alton chamber was about twenty Annhes.

The first fiv e runs at Becco were a simulation of the combustion chamber-a

arrangement thAt proved successful in t'~runs at EFS (Figure 26). All subsequent

tests incorporating changes to be described later, were compared to the simu~latedInAlton grrangement. The changeg made in the chamber configuiration and fuel spray were

an attempt to study configurations which might yield significant increases in

performance over that attained -in Runs 1 through 5 or at least to point out fruitful

avenuea-of Approach in future. combustion chamber development work utilizing decomposed

H~a02 and fuel.. Emphasis was placed on evaluating as many configurations as poSil

-27

CONFIDEN.T IAL

rather than gaining optimum performance for a few changes. Therefore, the test-

results are to be considered is preliminary only. A schematic jlagram :or the test

system employed at Becco is shown in Figure 27.

Runs 1 through, h were conducted for system check out and to familiarize

operating personnel with test procedures.

Run No. 5 gave results for comparison with later runs, Table VII. All tests

were of approximately 5 minutes duration and utilized diesel oil as futel. Run No. 6

was made at increased flow rates and chamber pressure and indicated 4 slight decrease

in C02 (82.3 vs. 81.6%) correlating with slight COP decrease with increased pressure

obtained during runs at ES. The fuel spray pattern for runs 5 and 6 is shown in

Plate 1.

The first change in the combustion configuration was an attempt to reduce the

size of fuel droplets. Both Arde Associates and the engineers at Becco favored the

* approach of reduction of fuel spray droplet size. (5) A Monarch #70-806 hollow cone

nozzle was used together with the flat baffle for Run No. 7 (Plate 2). C02 decreased

from 82.3 to 75.4%. In runs 5, 6, and 7 operation was oxidant rich. Correction for the

oxidant rich combustion was approximated by subtracting the volume of excess 0

from the sample volume.

Run No. 8 was an attempt to increase the ,chamber performance by lowering the

diluent nozzle to increase the effective combustion length from 4to approximately 5

inches. No increase in COe was noted. Combustion was fuel rich which accounted for

the increased chamber pressure with lower C02.

(5) "Analysis of Combustion in the Alton Chamber" Dr. E. Mayer, B. J. Aleck, ArdeAssociates Report No. 2567-1.

C NF T D ETIAL

..---

CONF IDENTIAL

* For run No. 9 ths fuel spray droplet size was further reducold by employing a.

#28-60* Monarch hollow spray nozzle (Plate 3). The percentage of 00 in the non-con-

densibles of the exhaust gases was lower than Run 7 which employed a #70-800 Monarch.

Further reduction in droplet size was considered useless.

Runs 10 and 11 wereto evaluate solia.spray nozzles (Plates 4 and 5) and

indicated an increase in CON" with decreased droplet size.

Run No. 12 incorporated a fuel nozzle configuration that had proved

successful in previous test work at Becco. The arrangement utilized a bluff body

type flame holder (Figure 28). The fuel tip was a #70-80* Monarch. A comparison of

runs 7 and 12 indicates excellent operation with the flat flame holder.

Because flow patterns about a conical flame holder appeared to give more

intense mixing(° ) a conical flame holder was installed for run No. 12 (Figure 29).

Performance decreased.

The "straight through" head arrangement (Finire 30) for Run 14 was evaluated

to explore the possibility of a simpler head design in comparison to the trestricted"t

entry used in the previous runs. Performance decreased. An interesting effect of

the use of flame holders was noted. The straight through head insert had never been

exposed to high temperatures before the run. After the run an inspection of the insert

revealed only very slight discoloration of the metal. The flame holder stabilized theF?combustion in a manner that eliminated high heat transfer to the head section.

Runs 15 and 16 incorporated a rather drastic change over the general

configuration tested at EES. The fuel tip was installed in the diluent spray nozzle

giving "reverse flow" fuel injection (Figure 31). It was hoped that the stay time;

---- ---- -- -- --- -- -- -- -- -- ---- ------(6) "Some Experimental Techniqueg for the Investigation of the Mechanism of Flame

Stabilization in the Wakes of Bluff Bodies" H. M. Nicholson, J. P. Field, LWdr,

USN, Bureau of Ordnance, Contract NOrd 7386C 0 N F I D E N T I A L

-,29-

C ONF TDENTIAL

ise." the length of time each particle of fuel could burn before being quenched byI ,'1

the diluent water spray, would be greatly increased thus assuring efficient combustion.

0: A baffle was installed just below the throat at the liner inlet to prevent any fuel

from being sprayed into the uncooled chamber below the catalyst bed. The fuel sprays

were checked before each run by removing the catalyst chamber and baffle at the head

and observing the amount of fuel spray emitted through the throat of the head insert.

Very little fuel was sprayed out of the chamber with the #70-80* Monarch at rated

flow. Considerable spray was emitted when the #50-350 Monarch was installed. Runs

15 and 16 gave poor results. No difficulty was experienced with light off and chamber

pressure remained steady.

The preliminary conclusions from the H-O , decomposition liquid diesel fuel

injection tests made at Becco are as follows?

(a) Reduction of droplet size in a hollow cone spray by increasing the

pressure drop across the fuel nozzle will not increase combustion

ef ficiency.

(b) Decreasing fuel droplet size with a solid spray increases combustion

efficiency.

(c) "Restricted entry", flat flame holder below the throat, will give good

operation and reduce heat transfer at the head of the liner.

(d) "Reversed flow" fuel injection as performed resulted in poor

performance.

.(e) Removal of the restricted HP.Og decomposition gas entry passage decreases

performance..

(f) A flat flame holder gives better performance'than a conical flame holder.

In addition to the combustion tests, flow tests were conducted with a

plexiglass mockup of the combustion chamber. An attempt was made to obtain a picture

, ,. C 0 N F I D E N T I A L

-30-

CONFIDENTIAL

of a 2 dimensional flow pattern within a 3 dimensiVnpl flow (Figure 32). Nitrogen

and. entrained aluminum particles passed through the mockup. Difficulties-experienced.

fabricating the plexiglass and obtaining satisfactory pintures within the short

test period (Plate 6) prevented the possible use of the flow pattern pictures iL. the

seleotion of test set-ups that would give better performance. The degree of

correlation between the intensity and geometry of turbulence obtained with the

plastic chamber and the performance of the stainless steel combustion chamber would

have determined the usefulness of the plastic mockup. More development work is

required before adequate flow pattern pictures can be obtained with a 3 dimensional

mockup of a combustion chamber under consideration.

The shortness of the test program prevented experimentation with other

types of fuels. An analytical description of combustion preparedby Arde Associates(7 )

for Becco predicted a gain in combustion efficiency when more volatile fuels than

'diesel oil are burned in a given short combustion chamber.

A summary of the analytical description of combustion is presented in

Appendix A.VIII, Conclusions and Recommendations

Full power operation of the H10 2-diesel fuel Alton combustion chamber

called for maintaining 75O psig chamber pressure and 1300OF exsaust continuously

for ten hours with a minimum of 90% CON by volume in V.- n,,n-condensibles of the

exhaust. The combustion chamber developed during Project "Hill" demonstrated near

full power operation for 2-1/2 hours with an exhaust temperature at an average of

approximately 1200"F in run 72-12B. The C0 of the exhaust during the 2-1/2 hour .

run was well above the minimum of 90% and the combustion chamber liner burning that

(7) loc. cit. Arde Associates No. 2567-1

. 0 NF.'TD"E 1'T IA L

-31-

C 0 NV! Fl T E NT T A L

occurre.d diuring full power op.et ion 0'o l!.or, system was eiiinaltcd. 1 4 ~s

Bocce Is opinion that the c'-- er e~hbor con~r,,rtin Lest. wa~s empToy#%d in run

72-1.2B could operate successfully (it full power for ten hours. As mfntioned 'earlier,

the final. run configuration was operated at 750. psi,- chamber~ pressurR for a slaort

time in run 67-12B without causing any liner damage. In addition, if 90%. HOof

slightly greater purity than that, on hand at FRS were employed in a 10 hour test, a

samarium treated silver screer cnt.1'lyst ',)d cotlid he expected to provide satisfActory

decomposition for the duration of t):,- te-st. The- catalyst difficulties experienced

half way through the Project "HIll" test rrcf-rm prompt the previous statement.

The '-lowni- -'-;fications might prove to fur+he-r incrf-.aso the relin'bility

and/or simplicity of the Project "Hill" chamnber:

(a) Substituticn of' a properly located central spray- diluent nozzle fed

f from four plain pipes for -the cooling ring, four nozzle diltentarrangement.

()Installation of11 a 3/bj P T)e Spray ring in place of the 3/8"1 cooling

ring and removal of the four spray nozzles. The larger ring would be

drilled'to provide a spray against the bottom of the liner to accomplish

the affect of the cooling ring addition. The larger ring, could also be

drilled to provide a cone, of flame quenching diluent water in the bottom

cof the combustion space..

(c) Removal of the slotted ring baffle from the fuel tip, increasing the fuel

tip length, and the addition of s hl' diameter flat flame holder -to give a

configuration similar to tho flnt flamre hiolder -- restricted entry

arrangement that shonwed promrise during the tests at Bec~oo of maintaining

high acombu st, o a ef f iG ie MICrhile eliminating the cooling prot~lenis in the

head section.

C0 NF ID ZNMTA L

2'I

C 0 N F T D E N T L

Additional combustion studies could be made at Becco .in order to reduce

the development time renuired for the proper operation, of a HROn supported .o'mbustion

system. The information obtained may also contribute in a small way to the better

understanding of the whole field of turbulent, high pressure combustion. Develop-

ment work with HnO2 decomposition gmses to which a .7-wirl is imparted as was done

with the swirl vanes on the fuel inlet of the Alton chamber and with the Arde dual

swirl nozzle tested during Project "Hill" could be continued. Such general

combust;onconfigurations using air can give high heit release rates while maintaining

relatively. coolirng combustion chamber w.alls.(8) Reverse flow fuel injection could

also be investigated further, Such an arrangement shod'.( provide the intense mixing

that efficient combustion requires. In fact, the configuration run at Becco

probably provided too intense mixing. It appeared that the turbulence inifide the

chamber during combustion caused a blow out of the burning of the heavier fuel

fractions and consequently poor combustion.

More volatile fuels than diesel oil may prove to be more easily deptable

to an H202 iupported combustion chamber. The relations developed in the Arde Report

summarized in Appendix A, indicate that more volatile fuels would give more trouble-free

operation.

More exact design parameters could be developed for the restricted-entry

flat flame holder arrangement.

Finally, an approach to the problem of the development criteria for

successful chamber design was only begun in the test work at Becco described earlier

in this report. The possibility of proving the existence of a correlation between

the geometry and intensity of turbulence obtained by photography of a non-combustion

(8) "Flame Stabilization in Gases Flowing Cyclonically Flow Characteristics,Temperatures and Gas Analysis" L.F° Albright, L.G. Alexander, University of

Oklahoma

C 0 N F ID 1 N T I A L

33'

i -C

"C 0 N F T D N T T A L

plastic chimber mockup and the combustion efficiency obtained in the steel

counterpart appears attractive. IT such a correlation exists, considerable

developmentb work could be donewith inexpensive fluids (nitrogen and aluminum

particles). This general approach could be carried one step further if the first

phases aescribed above are successful. Glass wall combustion chambers together with

Schlieren photography and flame ionic probes could then be used to more fully

describe the actual flame. The existance of a correlation between the plastic

mockup flow patterns and the local conditions of temperature, velocity, and degree

of reaction obtained by Schlieren photography and ionic probes would give useful

data to the entire field of turbulent cf'mbustion renearch. The affects of flame

generated turbilence would be the least that would be obtained.

IA

- ,'I

4r

C O N F ID E N T I A L

- - - - -- - - -,

s'i " " " " .. .. .. . .. .... ..." .. .. .. .--- " ---. :.. . . . -. .. . .. : ... . . .--- 3 4 ....--. . ...- ' . .

TABLE I

TEST DATA RUN #68 mcm'im cC-12 COMBUSTION CHAMBER

Date 18 January 1953

Combustion Chamber Pressure 728 psig

Waber/Huom ratio in gals. 2.00

Piel/HaN ratio in gals. * 210

Catalyst Chamber DisoW, Temp. 1255F

Comb. Chamber Disco Temp* 1200*F

Coolimg water to combo oh. Tempo 111*7

Diluxent to spray-Okozzles temp. 301i F

Dilumnt to combo co. pressure 800'paig

4P across diluent spray nozzles 72 psi

Fuel to comf, at*. pressure 775 peig

'A P fuel injector 4~7 psi

Tim ex fuel 5,minutes

Total flow 52,682 #/hr.

C0NFI 1- N T

- 35

C. 14 F I D E N T. I A L

TABtE- II

INSTRUMEVNTATION AT EES.

Pressure Temperature

luid or Material Lo cat.ion Gage' Recorder Gag Recorder

2 decomposition gases catalyst chamber dischargetA

xhauat gases from comb. steamr separator A

chamber

exhaust lipe loop e

to desuperheater

t~o .-ondenar ei

Nater booster pump disch. .

triple £eed'pump suctilornW

triple feed puimp discharge 7Hproportioning de-rvice outlet V/

-to' combustion i:hambfir c-,ooling

to ttlyst thamber cooling W-0passages

II to dilueni nozzles V

from cooler

Hto desuperheater V

combustion c-hamber cooling 3-jacket*

Seawater to condenser.

HClbooster pump disc.,

triple feed pump disch.W1,-0

itafter throttle volve we"'

ole booster pump disoli. _ __O

- ~ 7T6

C O N F T D EN T T A L~i

t TABIE 11I (coutcL)

aessure TemperatureFuid or Material Location -Gage ReciFe- Gage 'Recorder

Fue triple r eed pump suct.

Htriple feed pump disch,

proportioning device outlet

to combustion chamber W-*(after solenoid valve)

Steam Condenser shell

Control air after solenoid valve

Lbe oil to triple reed pump

from triple feed pump P-

rrpefeed p-ump 3-upper sleeve bearings

3-lower sleeve bearings

3-ballbearings

~' " housing

dombustion chamber themocouple, wires .28 -

liner peaned into wall*

* located as per dwg. SP 859-R2

C 0N F I DE NT IA L

JA

CONF IDENTTAL

TABLiZ III

HWRN 5-12B SUMMARY DATA

Date: 17 February 1955 Wall and Jacket femps. 1F

Combustion Chamber Press. 650 psig Liner wall temp.p domeos 97.9% Wi -o, 1.71% WIA -

0 .13% W2 3522 .21% W3 361

ater/H202 ratio, gpm 1.96% W3Ael/Hc02 ratio, gpm .206 W 230

at. chamber discharge temp. 1320!F 3-1/8""' from throazomb. " " (Sep.) temp. 11806F W525

(loop) temp. 116oeF W6 534Cooling water to comb. ch. temp. 68OF W7 509

temp. 192OF W8 495W9 356

Diluent to spray nozzles, temp. 198*F WIO 660.-il 500

ecirculating pump on202 after throttle valve, press. 700 paig h-1/8" from throat

W13 483iluent to comb. chamber, press. 700 psig Wll 765

W15 665el to comb. chamber, press. '670 psig w/ vw6 400

4-15/1611 from throatTime on HnO2 46 #min. 30 sec. WI7 -

IW18 682rime on Fuel 37 " 55 IW19 330

W20 9335-11/16" from throat

W21 218W22 734W23 -W24 752

10-1/8" from throatW25W26 199

Jacket Water dome31 158J2 244

- K 3-1/8" from throat J3 .143J4 157

5-11/16 from throat J5j6 140 ..

10-1/8" 1 1 J7 121J8 114

" 18-1/8" " J9 11.*J1 94

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TABLE IV

RUN 62-12B.

DATA WMFORE An) AFTER TEVIERATURE CIHANGES

__Before After

COo 95.1 93.3 5-11/16" from throat W22 375 213Cooling water to comb. ch. "F 60 65 W23 220 167

W24 211 168Cooling water from comb. ch. OF 204 160 10-1/8" from throat W25 300 310Diluent to nozzles *F 215 175 W26 340 197Recirculating pump Off Off 18-1/8" from throat W27 280 126Wall readings dome W 1A 298 190 W28 127 228

W2 420 225 Jacket water, Dome J 1 189 153W3A 365 203 " , J 2 184 154114 272 185 3-1/8" from throat 'J 3 175 150

3-1/8" from throat W5 317 209 " " " J 4 185 15416 335 192 10-1/8" from throat J 7 146 148W7 266 190 J 8 144 147W8 267 190 18-1/8" from throat J 9 101 122W9 250 177 It " " J 10 102 100

O 10 425 220111 35 220

4-i/8" from throat W 14 220 153, W 15 221 167

4-15/161, from throat W 18 250 178W 19 213 168W 20 240 172

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In addition to designing liner No. '49 presenting the dual swirl nozzle, and

making a preliminary analysis of the fuel spray in the modified Alton combustion

chamber, Arde Associates of Newark. New Jer. ey, wa, contracted by Decc to develop

an analytical expression of turbulent, HlO . supported high pressure combustion! 9

The report is summarized here to show the excellent correlation between the

performance predicted by tle expressions developed in the report and the actual

performance of the modified Alton chamber. The foctors that would increase

performance as indicated by the expressions developed are, therefore, substantiated

within the limitations imposed by the tonditVns not taken into account in the

A erivations.

The report develops art enuation from which an approximation can be made of the

time required for the complete burning of liquid fuel droplets sprayed into a high

C pressure combustion region supported by the decomposition products of HqO 2 . The

derivation begins with the consideration of the burning of a single droplet in

static oxygen-rich msrroundings. The model assumed consists of a spherical liquid

droplet surrounded by a concentric spherical flame of negligible thickness. The

flame is located at a distance which is determined by the location of stoichiometric

proportioning of evaporated fael diffusing outward from the droplet and oxygen

transported and diffused toward the flame. The products of combustion spread

outward from the flame. The principle additional assumptions made were as followst

(a) the heat value, thermal conductivity, specific heat, and diffusivity of

each unit mass of evaporated fuel are constant.

(9) loc. cit. Arde Associated 2567-1

CONFIDENTIAL

- - -A ---

(b) the temperature is uniform throughout i" 4& iNlet and equal to the

boiling temperature.

(c) the fuel droplet size changes slowly, therefore a steady state situation

is assumed.

(d) the fuel diffusivity is directly proportional to the evaporated fuel

density.

(e) the pressure is constnnt throughout the model and equals 1 atmosphere.

The fuel life time calculated by the equation developed for the single droplet

is found to be close 'to the time measured by experlmentation l ) calculated X lO0 97%.experimental

The single droplet theory is modified to take into account the affect of the

high combustion pressure developed in the EES chamb--. hu cffact of the depletion of

oxygen as combustion proceeds is found to be small ana L "7ected. The fuel life

( time expression thus modified is used to calculate the time reouired for complete

combustion in the Alton chamber; te- .045 seconds. The icbual fuel residence time

calculated from experimental date is approximately .035 seconds. The calculated

residence Lime predicts a combustion efficiency that is approximately 10% lower than

that actually obtained with the EES chamber.

The following conditions not taken into account by the derivation are discussed

in the reportr

(a) thL fuel spray is composed of droplets of many sizes; the droplets larger

than the mean tend to increase tb; those that are very small burn with the

rapidity of premixed combustible gases which is so great that they, in

effect, contribute nothing to the mean lifetime and could therefore be

excluded.

(10) Godsave, S. A. E., Fourth Symposium on Combusticn, Pg 81., Williams and Wilkins,

Baltimore, 1953

A2

(b) the larger fiael drople,!: w: ud e defonned by drag forces which wciuli

Inor-Ease their burninn -a t~y increasing their surflace area., (increased

evaporation rate).

()the turbulent combustion causnd by swvirl vanes cr h,.'ffles- in the

decomposition gases would delcrea!se tb

(d) because of the geomnetry of the central fuel nozzlo spray in -the Alton

chamber a finite tirne delay exists until mixinga conditions approaching

stoichiometric are est !hIished.

(e) the lack of internal circulation in, thte smaller fuel droplets promotes

preferential vaporization of the LghF~ter fuel fractions. This could

lead to carbon formation and incompolete combustion.

The formula developed for tb is used to compare the effect of the use of

different fuels., Both the formula and test data from various literature sources

show a definite gain in combusticn efficiency in the modified Alton chamnber would

be attained if a lighter hydrocarbon fuel than the diesel oil were emrloyed.

The formula also predicts a decrease In fuel droplet lifetime for smaller

droplets. A comparison cf various sized droplets was made du6ring the3 tests at Becco

and showed smaller droplets to yield inferior results. It might be expected that the

increased velocity of fuel injestion reduced the stay time in the short chamber at a

faster rate than the life time was reduced by smaller drcplets. As the effective

length olf the combustion zone in the Becco chsriber was 1AL that of the modified

Alton chamber., it could be expected thal the efficiency would 're lvwasr th*1-on: that

experienced in the modified Alton chamber.

A

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