ASGRO® Fracture Mechanics and Fatigue Crack Growth Analysis Software NASA JSC Team Royce Forman Dr. V. Shivakumar Dr. Sambi Mettu Joachim Beek Leonard Williams Feng Yeh Southwest Research Institute Team Dr. Craig McClung Joe Cardinal Source of Acquis iti on NASA Johnson Space Center o https://ntrs.nasa.gov/search.jsp?R=20100042296 2018-05-25T22:06:21+00:00Z
14
Embed
Fracture Mechanics and Fatigue Crack Growth Analysis Software · PDF file · 2013-04-10Fracture Mechanics and Fatigue Crack Growth Analysis Software NASA JSC Team ... FATI GUE CRACK
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
ASGRO® Fracture Mechanics and Fatigue Crack Growth Analysis Software
NASA JSC Team Royce Forman
Dr. V. Shivakumar Dr. Sambi Mettu Joachim Beek
Leonard Williams Feng Yeh
Southwest Research Institute Team Dr. Craig McClung
¢ Determines safe stresses for a specified lifetime
• Provides specification of fracture control plans at the design stage ¢ Determines safe lifetime for a specified design
¢ Determines required inspection intervals (if any) to maintain safety
• If damage is discovered ... ¢ Determines safe remaining life (if any)
¢ Determines required inspection intervals (if any) to maintain safety
• Accurately simulates crack growth and failure in real structures ¢ Calculate fatigue crack growth rate and remaining life
¢ Calculate conditions (loads, crack sizes) that cause failure
-------------------------
5
NA
SG
RO
.
z l>
en
C)
;:tJ o @)
c:
en CD - ::l en _.
C.
CD z l>
en
l>
o II:
" NASGRO® Components:
Crack growth module ~ z
• Calculate fatigue crack growth or component life, critical crack sizes, or stress intensity factors for a library of 50+ different crack configurations
• Multiple crack growth equations
• Elastic-plastic crack growth analysis
_.DI25J Fie Options Tools ~
l' Ell 5electGe"""",YrlL' ~Mote''''1 ~ oer.,.specb-"'ITI .outputooik,n.lll Computotionsoodoulputl
I Co<"", Dock ,::J J CC02 . ot 011 •• 1 hole i1 pial. :::J
Thicknest. t ~ Wdh.W
J1s8 Hole diomete!.O 1501 Hole cb-to-edge di.c B
J1.99 Poitson tabo, nu
10 3
IrlbaIftawsi2e. a 1.031 h~tialtJ!c
r;:r
Inlial flow option r. lJ~entr.Y
r NASA SId NOE
ess FI fot context-sensitive~, F2 for general help
• Store, retrieve, and curve-fit fatigue crack growth and fracture data
• NASA database: • 476 different metallic materials • 3000 sets of fatigue crack growth data • 6000 fracture toughness data points • Statistically-derived crack growth equations for all materials
• Users can create their own database ~..,JtI!l!l 1\ilrtl!!!l1 _Iolx l
Fie Optlons T ods Help
B3 Select Gecmelly IL Choo:eMate<i.oll~ oe/;,.speclIumfo ollputopliomi fl Computotiomondoulputi ·'----l f MotOli.olPIOP.rtysol 1 --~" --.----~ ----~----"'~. ~ r Non Irtefacbon Select data souce----, Avaeb/e dalctl ""oct:. data fOlm¥s J (' 80mg ConsL Do.Uf. fr. NASGRO 1Ml0li.0l1ie r. NASGRO _ con~"" r Hlloble
1 ("J GeneraizedWiIenbofg II r Usef rMterial tie ! r ES):)NLA t.-Q:~.!IIit.mt~;.'l;rt~I'''... r 1,P lJ.i:tle ~I~ dt: r · ChongWllerbag ! r New dat, i r \II""" ~"",,,,, _"1_ r AP toOl'); dll'<W' ~Str~Yiefd I •
II Typical NASGRO® analysis: en ,.=1 Crack growth or component life calculation
• Problem: • Actual crack or flaw is reported in component
• Hypothetical flaw: assume worst-case scenario based on applied loading, component geometry, and crack location
• Analysis input: • Crack and component geometry
• Component material
• Load type and spectrum
• Analysis results: • Fatigue crack growth rate and remaining life
• Conditions (loads, crack sizes) that cause failure
• Safe stresses to attain a specified lifetime
• Component inspection intervals for safe operation
9
~ ~-
I NASGRO Sample Application: I " Orbiter feedline flowliner crack analysis 2:
• Objective: To determine the service life of the Shuttle Orbiter flowliners containing cracks by using a fracture-based assessment to account for crack propagation
Solution: Use NASGRO's Boundary Element Analysis module for its
• CAD-like drawing tools to custombuild crack model
• Computational core to calculate crack driving force K
!2l 1 ~[ml llllra l §llt l -I ;l l ~ 101···1 -I t H 11+H ~ tal@I€t1 'T~page 0, ... Segmer<. I p'oo. I segmert.l Zone._ Bourod¥;.. 1 H .... IlooOOg I Pnt I.OJId< I Gen, Docl<o I Spec, C,acl<. 1 101_1 c.Ic,/E><ec, I O'-"P<A I
, 3.9
'65
'66
-1,2
~:mm;ttl.4_ Dehne Zone;. Replot Change Scale I Undo Seg Undo Be I COORD [
Place ClJTSOf on ~ t~ get IlfOflnation
'58
, 4 ,4
e:;:ru- inch
4
12
~.~.----. ---_.
I NASGRO Sample Application: I II Orbiter feed line flowliner crack analysis
• NASBEM results used in concert with other tools (e.g. NASTRAN structural analysis code) to determine:
• crack growth between flowliner holes as function of flight service history
• flowliner service life
2 .5
2
::.: L
.3 1.5 tl
'" u.. ::r. ....,
.~
'" c
NASGRO/ NASBEr1 Resu 1 t s of Fl ow 1 i ner CT ens i 1 e Loaad i ng)
• NASGRO is used extensively around the world • Standard code for analysis of space hardware for NASA and its
international partners
• Supported and used by 000, FAA, and private industry in aircraft, rotorcraft, turbine engines, and many others
• Spaceflight systems for future space missions will use innovative materials and methods of construction • New materials will require testing and characterisation for their
properties for use in fracture analyses
• New systems, components, configurations, and manufacturing techniques will need to be certified for flight