NASA Technical Reports Server (NTRS) 20020092019: Shuttle Fuel Feedliner Cracking Investigation

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by  NASA Technical Reports Server (NTRS)

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Space Shuttle Fuel FeedLiner Crackin8 Investisation
MSFC Fluids Workshop
November 19-21, 2002
TD63/Tom Nesman
@
,_"i Introduction
rlar:h_l!_p_c_ri_t c_:_J
Cracks found on allorbiters fuel feedline bellows liner --) fleet grounded
Nearcleaning slots in liner
Cracks from 0.1" to0.3" in length OV103, OV104, &OV105
Slot-to-slot cracks OV102
JSC-.) Three manasement teams
Representatives from/_SFC
Seventechnical teams reporting to one ofmanasement teams
Participants from NASA(JSC,KSC8 MSFC), Boeing, USA,&Arrowhead
Fccdlinc frommanifold tocnginc inlct (typical)
MSFC Fluids Workshop, 11-19-02 Space Shuttle Fuel Feedliner Cracks Investigation 2
Significant Activities
toPursue [orNext (andsubs]Flight
Significant Findings Repair and Flight Qualification Work
3different ducts on orbiter (Engl, Eng2, Eng3) Repair method validated with coupon tests
Lox El LH2 ducts are identical Orbiter liners repaired --) weld cracks, grind and
Orbiter duct cracks specific to LH2 duct" smooth
Cracks only in bellows |iner closest to engine Testing -) single engine hotfire data 4" upstream
Cracks all originate at aliner slot of LPFP flange
Slots are stamped (leaving vertical indications) h_oda[ tests of liners (air and water)
Cracks found after initial rex duct qual test Refined load analyses (vibrations, acoustics, flow)
series (attributed to over-test) Failure analysfs of cracks
After initial quaL, liner redesigned Etrequatified F_Jmp _i2_
Liner material: CRES 321 to INCO 718
Number of slots: 76 slots to 38 slots i_r "/
OVIOZ £tMPTA old design ...others new design
Right-type ducts not used on SS/aE single
engine tests
Reassecl flight data E analyses says qual OK
bellow 1000 HZ
AnaD, zed material is 01( without significant
manufacturing defects (spare liners)
Installation test shewed no damaging strains
Byanalysis
Pump excitations can excite liner modes
with high stresses at all crack locations
•OnlyEng!and Er_2found rohayeflowllner crocks
MSFC Fluids Workshop, 11-1%02 Space Shuttle Fuel Feediiner Cracks Investigation
Elements of Crackin 8Analysis
1. Failure Analysis ..) LCF, HCF, overstress
2. Material Capability Material properties in LHzat T and P
3. Loads
-') Static, dynamic, transient, flow, vibrations
4. StructuraIModel -]_ Natural ['s, mode shapes, stress, FSI, coupling
The evaluation of cracking mechanisms isaccomplished through the four analysis
elements listed above. To be credible, apostulated mechanism must have
sufficient definition in terms of each of these elements. In most cases a
conservative estimate with asignificant variance istraded versus the investment
inobtainin_l adetailed definition.
MSFC Fluids Workshop, 11-19-02 Space Shuttle Fuel Feedliner Cracks Investigation 4
Fluid Driven £rackin8 Analysis
Crack initiation andgrowth requires adriving mechanism or load
HCFcracks atregular repeatable locations (pattern) could becaused byadriving
mechanism that iscoincident with astructural mode (resonance)
There are three parts to investigatin8 potential fluid driven cracking
I. Compare potential load mechanisms to structural modes
• Forced response., periodic load and structure mode frequencies are not coincident
• Random excitation ...structural mode exdted by random amplitude forces
• Resonance ...periodic load is coincident with structural mode frequency
2. Determine changes in frequency of load and structure durini3 launch vehicle ascent
, Frequency coincidence may only occur during throttling
• Frequencies may coincide for limited parts of main stage
• Frequencies may coindde for duration of main stage
• Frequency coincidence may occur differently on each engine Ivehicle combination
3. Determine toad andresponse patterns (spatial variation)
• Structural mode should have highest stresses at crack location
+ Dynamic load should put energy into structural _bration
• Structural "lock-in" should be considered
MSFC Fluids Workshop, 11-19-02 Space Shuttle Fuel Feedliner Cracks Investigation
_ _II
Coordinated Effort
/_SFC Fluids Workshop, 11-19-02 Space Shuttle Fuel Feedliner Cracks Investi_lation 6
._.__.._ Liner Structura[ Modes
•Thelowestfrequencymodeofthedownstreamflowlineristhe6_diametralshownbellow
•ThlsIsbecausemldwayfromtheweldedendtheonUleveredcyflndricaslhelltransiUonstoasmallerdiameter
•The6mdiametralmodeputshighstressesatalloftheo'acklocations
Hoop Dynamic Stre_ Axial Dynamic Stress
Fb+MbyED21/ Irad_
MSFC Fluids Workshop, 11-19-02 Space Shuttle Fuel Feedliner Cracks Investigation
Bettows Structural Modes
I=EMb_ED2I/I radi
MSFC Fluids Workshop, 11-19-02 SpaceShuttieFuelFeedtinerCracksInvestisation 8
Structural Motion in a Fluid
2000_ i QS_ed LH2 '-..... 10=- _-- OMe_Jr_d wet
1.00_ ._o_i_o._2_s:_o>I
g L R2=0.1947
N _ 0 0
_ r
_,ooo! o
OOo!
0 2 4 6 8 lo t2
o 2 4 6 8 io 12 Numbe_ofNodalDiameters
Numb_ofNodalOBmete_
•Structural motion inliquid hydroEen will bereduced In
frequency andma_initude compared toair 1800_ _M_sured -Drv I
•The retarded motion isrr_deled Llsin8anadded massand
anincreased dampln_
•Forthe downstream rue[ feedliner the frequency {above
[eft) and damping {above right) cham3e inwater was
predicted, then measured
•The same mode[ wasu_edto predict the frequency chan_e
duetoLH2 (right) and compared towater data scaled to 6001
LH2 4OO-
0 2 4 6 g io 12
NumberofNodalDiameterI
MSFC Fluids Workshop, I1-I9-02 Space Shuttle Fuel Feedliner Cracks Investigation
@
Fluid Borne Drivers
6000 ........... _-_- -- - --_I
-,_:-- Line[ Acoustic Modes
:................ '_ DuctAcousticModes I
..... I Liner Struct Modes
500O
2XBladepass(8N) I
O--- ............. 4D _ ROtCar
4000-_ i.... Alt BladeCar i
:..... SingleBladeCar
O-......................4{3 L auto-oscillation3-
3000
2000
1000
0
13,500 14,000 14,500 15,000 15,500 16,000 16,500
LPFP Speed (RPM)
MSFC Fluids Workshop, 11-19-02 Space Shuttle Fuel Feedliner Cracks Investigation I0
3-D CFD
_l=_hzq_e n_ ce.te_
3DCFD(TD64/Dorney) providespump
backftow inline and alsoin Liner/
Be[towsbackingcavity. Thisshows
amount offlow inandoutof thestets Slots and1Backlno Cavity
and alsotheAptoad ontheliner. (thisis Jim20 ooo
asinglephaseflow analysis, i.e., no
cavitation)
LH2 Fled Line LPFP Inducer
Instantaneous Static Pressure
MSFC Fluids Workshop, 11-19-02 Space Shuttle Fuel Feedtiner Cracks Investigation 11
Fluid Borne Drivers from Pump
Rotating Cavitation Forcing Function
pmthrum=_Oe_.e+
FlurdPhysicsandDynamics Group(T, Zoladz)
•Builds onMSFCcordflowlegacy
•Cavitabon flowloadsproved inwaterflow
•Mapped pumpcavitation regimes
° 3wavetheo_"
* Predictedwave forms for flow[iner loadingabove
-Wave formscalibrated using s_ngleengine data
r....T...... 2.....
_:.: I} ...... \
MSFC Fluids Workshop, I1-19-02 Space Shuttle Fuet Feedliner Cracks Investi+ation
AmpLification Mechanisms
Effect ofCavitation on Acoustic Modes
Acoustic Modes Between Liner and Bellows
10000 i j........ /GregFrady71i8i02 !
9000 _ _ !_ACOu_bcMCde_TD631Ca_lana:
i i
8000 _ I%v_po_ J
7000 _ :<2%Vapor
• i ° ........
Sc_10 _ _ L ............
@"40o0
2000 £ ,- × _,,_ ;_ x :'( 4, _"
1000: _ X x 4, .t. '1." 4,
0 2 4 6 B I0 12 14 16
Nodal Diameters
lh,d IAM b_11)63/('._,,_n_
13
MSFC Fluids Workshop, 11-19-02 Space ShuttLe Fuel Feedliner Cracks Investigation
_; Effect of Vapor on Acoustic Modes
i
10O00 4_Re:ED21/GregFfadv711a/02
9000 q_Acou_:JHcC,_ Ta63/CaSlano
8000 i t%_a_r
"c 7000 >:2% vapc(
6ooo
I•4%_apor
5000 _
_. 4000
3000 4, ,, :_ 9000
8000 •FEMAC_S_C14od_0%vapor
O56%
7000 12oi%
O_60%
2 4 6 8 I0 12 N 6000 [11756%
__ / Nodal Diameters _5000 t
/ =__ooo
/
_- 3000 t g • .t.
2000 _ ¢. ÷
_000 T
0 2 4 6 8 I0 12 14 16
Nodal Diametei_
MSFC Fluids Workshop, 11-19-02 Space Shuttle Fuel Feedliner Cracks Investigation 14
FLow Parameter Mapping
1,1._Pamra_l_r _,|Rpphi_ Data=neTlliee__Z-BlZ
T_ 902-813
Te__2-819
Te_9O2824
7_xxxl+ _ w ' Te_902-827
< J 1_8T_47
Tr8Te_49
h_'_liP" -_rs_ ; T_ITD84Te_B_[_kIIenglne
_'_iC_ BlOCk_engine
_('IK_•I . . .......... -. ,f_:.,.._=_7--,:_'_'_ _.--_'/" "_ ulM(nJl .
F_"allda_,_'N.and_ areb_odoff
{ /f'llt til: ...... ._..:-- < . . ..
- 25_. IN.330_. ar_2N
pm _t _ _rU_P
" • • .___ * s ....... 7
Te_t_2 data_l_ng
of_mp _._am_ne a_cels
L 1
x [ot ilis io7 MaOOiNQ_ charaL-t_,rizabon
Noresponse < 1.2RMS
Weakresponse _.1.2RNS
OV104 BIIand BIIA strongresponse>1.6RMS
•CavitationphenomenaobservedinSSME (from TD61)
data
• 2N:alternatingbladecavitation •Characterizaenddmappedthe25Hzresponse
• Cavitation instabilitieshave shown tomap well
• 330 Hz: rotating cavitation with
• 25 Hz: auto-oscillation cavitation and incidence parameters
MSFC Fluids Workshop, 11-19-02 Space Shuttle Fuel Feedliner Cracks Investigation 15
._ii! - Flight Engine Row Map
NSS vs. Q/N for the Last 15Flights
by1D611 Rt(¢,
00000 ....
45O0OI
O7 08 09 10
[131]_32](51o500s_onds fr<_mstart)St_cmds_em_t_rl
MSFC FluidsWorkshop, 11 19-02 Space Shuttle Fuel Feedliner Cracks Investigation t6
Summary I Conclusion
I_rs_llSpac_ nl_tCfr,_tr
Flow loads investigated aspossible driver for cracksfound inorbiter fuel feedliner
Analysis shows that pump excitations can excite liner modes with high stresses at allcrack
locations
Three aspects offluid driven cracking were investigated andit wasfound that
I. Pump blade passfrequency isthe only driving mechanisms that coincides with liner
structural frequencies
2. The time andduration of frequency coincidence isnot known dueto changes in
frequency of load during launch vehicle ascent and uncertainty inexact structural
mode involved
3. The lobedpattern from pump pulsations are most likely toexcite anodaI.diameter
mode of the liner
Ongoing testing should reveal information toimprove hardware life estimates
Liner response mode (or modes)
Accuracy ofliner delta p' estimate
Spatial p' mapping
MSFCFluidsWorkshop,11-19-02 SpaceShuttleFuelFeedlinerCracksInvestigation 17