From PragTicAFrom PragTicAto FADOto FADO

Jan PapugaJan Papuga

Czech Technical University in Prague

Dept. of Mechanics, Biomechanics and Mechatronics

Workshop on Computational Fatigue Analysis 2008 & 2ndWorkshop on Computational Fatigue Analysis 2008 & 2nd PragTic PragTic UsersUsers’ Meeting’ MeetingKamenice nad Lipou, Czech Rep., Oct. 29-31, 2008Kamenice nad Lipou, Czech Rep., Oct. 29-31, 2008

4. PragTicA4. PragTicA Project Project((PragTicPragTic in in AApplication)pplication)

Applied Applied to European Commision within FP7 to European Commision within FP7 schemescheme

Consortium of companies and universitiesConsortium of companies and universities Evektor, CZ (PragTic)Evektor, CZ (PragTic) Brno University of Technology, CZ (MSC.Fatigue)Brno University of Technology, CZ (MSC.Fatigue) CDM IT ASCR, CZCDM IT ASCR, CZ Centro Ricerche Fiat, ITCentro Ricerche Fiat, IT CTU in PragueCTU in Prague, CZ (Fe-Safe), CZ (Fe-Safe) Delft University of Technology, NLDelft University of Technology, NL Fatec Engineering, NL (fFatigue)Fatec Engineering, NL (fFatigue) IPM ASCR, CZIPM ASCR, CZ Materials Engineering Research Laboratory, GBMaterials Engineering Research Laboratory, GB SKODA VYZKUM, CZ (FemFat)SKODA VYZKUM, CZ (FemFat) Trinity College Dublin, IRLTrinity College Dublin, IRL University of Parma, ITUniversity of Parma, IT Vision Consulting Automotive, CZ (expected WinLife)Vision Consulting Automotive, CZ (expected WinLife)

PragTicAPragTicA Project Project Work areasWork areas

fatigue researchfatigue research accompanied by extensive accompanied by extensive experimental programexperimental program

comparisoncomparison of different of different fatigue post-processorsfatigue post-processors of FE-solutionof FE-solution

JointJoint PragTic development PragTic development with focus on with focus on notch effectnotch effect multiaxial loadingmultiaxial loading seam seam and spot and spot weldswelds rivetriveteded joints joints compositescomposites

It seems that we are close to rejection at It seems that we are close to rejection at this momentthis moment

Why PragTicA?Why PragTicA?Use of CommercialUse of Commercial SSystemsystems

Not including implemented standards, the software Not including implemented standards, the software

producers producers

do not present any more extensive verification of implemented do not present any more extensive verification of implemented

methodsmethods

if they implement some method or standard, the potential if they implement some method or standard, the potential

deviation from it are not verifieddeviation from it are not verified

It is common, that the It is common, that the producers disclaim any warrantyproducers disclaim any warranty

with losses caused bywith losses caused by the the use of their software use of their software

How the end-users know How the end-users know whatwhat they they computedcomputed??

There is There is nono independentindependent authorityauthority that would that would checkcheck

quality of different software solutionsquality of different software solutions

Room for Verification Room for Verification AuthorityAuthority

I - GoalsI - Goals Bridging of the gap between research Bridging of the gap between research

and commercial application should be and commercial application should be

verifiedverified Need for verification of Need for verification of

methods implemented in SWmethods implemented in SW

the implementation ways themselvesthe implementation ways themselves

new calculation methods where a great new calculation methods where a great

potential of commercial implementation potential of commercial implementation

existsexists

Room for Verification Room for Verification Authority Authority

II – Is there a gap? Researcher on the cliff RResearchers esearchers

often test their method on a small group often test their method on a small group of experimentsof experiments

the support of the support of thethe research group is research group is usually focused on the design of the new usually focused on the design of the new criterion and proof of its usabilitycriterion and proof of its usability

the extent of the proof depends on the the extent of the proof depends on the researcher and money invested researcher and money invested

once the method is once the method is said to be provedsaid to be proved, the , the only impulse to continue in the only impulse to continue in the verification is an attack started by some verification is an attack started by some other researcherother researcher

Room for Verification Room for Verification AuthorityAuthority

III – Is there a gap? SW producer on the cliff SW producers SW producers

are confronted with demand on are confronted with demand on implementation of certain calculation implementation of certain calculation procedures. procedures.

either use some older method, where is a either use some older method, where is a greater probability that it is known greater probability that it is known (~recognized !) by the end users.(~recognized !) by the end users.

oorr implement (design) some new method; implement (design) some new method; if they do some further testing of the if they do some further testing of the method’s credibility, its results are method’s credibility, its results are scarcely scarcely publicpublic

the decision what to implement is made by the decision what to implement is made by a small group of peoplea small group of people

Room for Verification Room for Verification Authority Authority

IV – The choice and what matters in it Evolution Rule in Implementations:Evolution Rule in Implementations: Why to Why to

select older methods for implementations?select older methods for implementations? The originators are either dead The originators are either dead (i.e. without doubts) (i.e. without doubts)

or highly distinguished man, who taughtor highly distinguished man, who taught a a great great number of engineersnumber of engineers

Even some engineers could hear about such a Even some engineers could hear about such a method at the universitymethod at the university

More researchers referMore researchers referred to such a method within red to such a method within all the yearsall the years

The scope of the validation is often betterThe scope of the validation is often better Example: Example: See the results of the Dang Van See the results of the Dang Van

method in FatLim and compare it with its spread method in FatLim and compare it with its spread in solvers and research papersin solvers and research papers

Conclusion:Conclusion: What matters What matters in this process in this process is is publicitypublicity level level and not the and not the performance performance

Room for Verification Room for Verification AuthorityAuthority

V - Warranty acquittanceV - Warranty acquittance Researcher:Researcher: Proposes a new criterionProposes a new criterion Proves its validity on data he has in handsProves its validity on data he has in hands His His only (vague)only (vague) responsibilityresponsibility is for these research results is for these research results

Solver developer:Solver developer: Selects and implements the methodSelects and implements the method I do not know about any case, where further testing was I do not know about any case, where further testing was

sponsored by such a company with publicly available resultssponsored by such a company with publicly available results Decides to what extent to release publicly details of the Decides to what extent to release publicly details of the

implementation (so that the competitors would not steal his implementation (so that the competitors would not steal his ideas)ideas)

Disclaims any responsibilityDisclaims any responsibility for the use of the software for the use of the software End user - engineer:End user - engineer:

Gets a very expensive tool in his handsGets a very expensive tool in his hands Due to high price is forced to use it to maximumDue to high price is forced to use it to maximum Does not have time enough to get through all the theoretical Does not have time enough to get through all the theoretical

basis or validation studies (if there are any available)basis or validation studies (if there are any available) Would like to believeWould like to believe that the previous two persons were that the previous two persons were

responsibleresponsible

QuizWho will be blamed if anything happens?

Room for Verification Room for Verification AuthorityAuthorityVI - ConclusionVI - Conclusion The fatigue solvers are very simple to use – it is not hard to The fatigue solvers are very simple to use – it is not hard to

generate a nice map of fatigue damage on some particular generate a nice map of fatigue damage on some particular structural elementstructural element

Fatigue problems and solutions are still empiricFatigue problems and solutions are still empiric Fatigue is a weak link mechanismFatigue is a weak link mechanism There is often presentThere is often present

quite a big scatter of experimental resultsquite a big scatter of experimental results important uncertainty as regards load levels and courses, important uncertainty as regards load levels and courses,

materials, ...materials, ...

The Help sections and the documentation of quality of used The Help sections and the documentation of quality of used methods are poormethods are poor

The end users of the commercial fatigue solvers are the only The end users of the commercial fatigue solvers are the only persons responsible for results they get from itpersons responsible for results they get from it

Are they aware of it?

Users can get quickly to complete results without adequate knowledge

what they mean

Lets Start to Change ItLets Start to Change ItFADO – Fatigue Analysis Documentation FADO – Fatigue Analysis Documentation

OfficeOffice Even if Even if PragTicAPragTicA fails, why not to organize the fails, why not to organize the

development in another way?development in another way? Consortium of companies and universities Consortium of companies and universities

Joint work can still produce adequate results for acceptable Joint work can still produce adequate results for acceptable money, only the consortium has to get bigger.money, only the consortium has to get bigger.

What can I offer:What can I offer: Understanding to problems both in programming and fatigue Understanding to problems both in programming and fatigue

analysisanalysis PragTic with an access to its complete source code can be PragTic with an access to its complete source code can be

provided to any interested companyprovided to any interested company Conditions:Conditions:

The code stays in the company and no its part is further distributedThe code stays in the company and no its part is further distributed Any derived application can be used only within the company or Any derived application can be used only within the company or

within the consortiumwithin the consortium The company gets involved in the FADO project by any of the The company gets involved in the FADO project by any of the

following waysfollowing ways

FADO - FADO - Fatigue Analysis Documentation Fatigue Analysis Documentation OfficeOffice

Your potential involvement:Your potential involvement: Experimental facility availableExperimental facility available Material provision, specimens Material provision, specimens

manufacturingmanufacturing Collecting other experimental dataCollecting other experimental data Financial supportFinancial support

Research workResearch work Programming workProgramming work FEA models FEA models

preparationpreparation Fatigue analysesFatigue analyses

The output for your moneyThe output for your money Direct influence on the next development of PragTicDirect influence on the next development of PragTic Understanding its limits and the limits of other solversUnderstanding its limits and the limits of other solvers Possibility to use the core structure of PragTic for your Possibility to use the core structure of PragTic for your

own goalsown goals Access to all the results gathered within the consortiumAccess to all the results gathered within the consortium A consortium generates adequate financial sum from A consortium generates adequate financial sum from

smaller partial depositssmaller partial deposits A dedicated website is currently being prepared A dedicated website is currently being prepared

(will be placed on (will be placed on www.pragtic.com/q_org.php)) Still needs to get the right momentum and enough Still needs to get the right momentum and enough

participants involved to start FADOparticipants involved to start FADO