structural fea models and results interoperability based on step...

DIESAR Direction Internationale de l’Evaluation, de la Sécurité et des Affaires RéglementairesAFNeT Standardization Days 2019

Structural FEA models and results Interoperabilitybased on STEP AP209

By

Albert Lévy (CIMPA on behalf of Airbus)Jean-Marc Crepel (AFNeT)

June 5 & 6, 2019 (Paris) – [email protected] - http://standardizationday.afnet.fr/ - ‹1›

DIESAR Direction Internationale de l’Evaluation, de la Sécurité et des Affaires RéglementairesStructural FEA models and results Interoperability based on STEP AP209

AgendanBusiness needs for CAE interoperabilitynOverview of STEP AP209 ed2nLOTAR Engineering Analysis and Simulation projectnCAE Implementor Forum initiativenLast updates/Highlights

§Definition and Implementation of FEA Validation Properties§AP209 Handbooks§Live « round-trip » demo at NAFEMS World Congress 2019

nConclusions



Business needs for CAE interoperabilityBenefits of standard-based interoperability


The exchange of digital information in a heterogeneous environment is enhanced if the format of the data is an internationally recognized industry standard:

• Designed for interoperability• Extensible to meet future needs• Maintained by subject matter experts• Supported by commercially available software • Independent of proprietary technology• Designed to maintain compatibility• Designed to be robust and reliable• Contains a means of validating that the data

preserves the key characteristics


STEP AP209 edition 2 "Multidisciplinary Analysis and Design" Support for Multi-Physics Simulation


Technical scopen Models, Analyses, Load cases, Resultsn Product definitions and structures, incl.

configuration informationn Finite Element Analysis

§ Linear static§ Linear modes and frequencies

n Computational Fluid Dynamics§ Based on the NASA/AIAA CGNS (CFD General

Notation System) standardn Kinematics

§ Rigid Body Motionn Generic Analyses

§ Based on the ISO Engineering Analysis Core Model (EACM)

n Material Properties (link with STEP AP235)§ Homogeneous (metallic) and Composite Materials§ Detailed specification§ Catalogue data

AP209 integrates 4 domains:CAD, CAE, SDM and PDMSDM : Simulation Data ManagementCAD : Computer Aided DesignCAE : Computer Aided EngineeringPDM : Product Data Management

STEP AP242 modules

AP209 specific modules

www.ap209.orgISO 10303 AP242 « Managed model based 3D engineering » isfully included in AP209

http://www.ap235.org/




LOTAR Engineering Analysis and Simulation (EAS)Participantsn Industry members

§ Airbus§ Boeing§ Lockheed Martin

n Facilitators§ AFNeT§ PDES, Inc.§ prostep ivip

n National Institute of Standards and Technology (NIST)


…to develop, publish and maintain standards-based mechanisms for archiving and retrieval of Engineering Analysis and Simulation information that can be read and reused throughout the product lifecycle, independent of changes in the Information Technology (IT) application environment originally used for creation.

Goals and Objectives

Technical Approach

http://www.lotar-international.org/lotar-workgroups/engineering-analysis-simulation.html

LOTAR EAS is based on ISO 10303 AP209

http://www.lotar-international.org/lotar-workgroups/engineering-analysis-simulation.html


Round-trip of a FEA model/results to and from an archiveusing AP209


Re-Run and validate

Target system

FEA Solver

Translated input data

New results from translated input data

Metadata, input data & results

AP209 ed2 translator

AP209 ed2 file

Archive

Source system

Fail

No

Translated results from original FEA

Equivalent outcome?

Recovered FEA for review or reuse

PassYes

Is the recovered FEA functionally equivalent to the original?

Ingest Access

Storage Vault

Long Term Archival and Retrieval (LOTAR)

Native FEA Data may be added to the archive

AP209 ed2 file

Metadata, input data & results

AP209 ed2 translator

The translator generates validation properties during translation from native to STEP

The translator generates data to compare to validation properties during translation from STEP to native

Original FEA


What is the CAE Implementor Forum (CAE-IF)?


nJoint testing forum hosted by AFNeT, PDES, Inc. & prostep ivip association

nComposed of CAx vendors as well as translation and validation software developers providing STEP translators

§ For CAD, based on AP242

§ For CAE, based on AP209 ed2§ Starting later in 2019, for Electrical Harness, based on AP242 ed2

nPerforms two test rounds per year for each domain

nPresents summary results to the user community

nDevelops and publishes Recommended Practices

nReports issues to the standardization community


Goals of the CAE Implementor Forum


nAccelerate CAE translator development

nEnsure that users' requirements are satisfied

nImplement functionality for today's needs

nIdentify functionality for tomorrow's needs

nAvoid roadblocks by establishing agreed upon approaches

nIncrease user confidence by providing system and interoperability testing

nEnsure new functionality does not adversely impact existing implementations


CAE-IF Testing Methodology


Translate to STEP AP209

Perform STEP AP209 file checks and report

findings

Participants access and process STEP files;

report results

Participants resolve issues during the test rounds

Detailed review at meeting

Translation based on:•Current EXPRESS•Latest (draft) Recommended Practices•Test Case definitions

Checks performed (1/2):•Syntax and Structure (conformance to schema)•Semantics (conformance to Rec. Practices)

Preparation based on:•Test suite selection•Test environment•Rec. Practice update

Preparation phase

Checks performed (2/2):•Translation results consistency (statistics, validation properties)

3 months

3 months

Workshop

Workshop

Workshop

To speed up the implementation and test of robust STEP AP209 interfaces


CAE-IF Roadmap developed by exploring 3 axes


Functionalities: • Elements types, loads conditions,

output data, control statements, …

Complexity:• From simple tests cases …• …up to vehicle level simulation models

Translation process:• input data file, output data • regeneration of original CAE solver input data, • including re-run (roundtrip process)


CAE-IF Roadmap



Definition of FEA Validation Properties


nA key STEP feature required by LOTAR is the use of Validation Properties

nFEA Validation Properties are characteristic values of a finite element model calculated from the native model data

nThey are computed by the exporting system and included as key-value pairs in the STEP file, with a specific format described in the Recommended Practices

nAny importing system will re-calculate these properties and compare its results with imported validation properties, thus determining the success of the data transfer.

NativeSystem

TargetSystem

FEA Data

FEA Data‘‘

Valid.Prop.

FEA Data‘

STEP AP209

Convert

Compute Compare

Convert

Import Compute


List of STEP AP209 FEA Validation Properties


nFEA input data§Nodes§Material properties§ Boundary conditions§Applied loads

nFEA output data§Displacements§ Stresses§ Strains§ Internal forces results

VP level Output data subset

Displacements Max translation/rotation vector lengthStrains tensor field Max/Min volume change ratio (strain) Stresses tensor field Max Von-Mises stress,

Max/Min axialMax/Min torsionMax/Min shear1 /2Max/Min bending1 /2Max/Min membrane_X /Y /XYMax/Min Shear X /YMax/Min Bending X /Y /XY

Validation property name

1D elements Internal forces

2D elements Internal forces

FEA results VP

VP level input data subset validation property name·Number of nodes·FEA model bounding box·Total length of 1D elements, Surface of 2D elements, Volume of 3D elements·Total volume of the model (including Section Area for 1D elements and Thickness for 2D elements)·1D elements-, 2D elements- and 3D elements- centroids·Total mass of the model ·Position (X, Y, Z) of the center of gravity ·Number of different loadcases·Number of fixed DOF (*)·Resultant of applied forces (Fx, Fy, Fz) (*)·Resultant of applied moments (Mxx, Myy, Mzz) (*)·Resultant moment of applied forces at a reference point (*)(*) depending of the selected loadcase(s)

FEA model VP

Discretized geometrical data

Material data

Boundary conditions & Applieds loads(*) FEA

loadcase VP


AP209 related document typology


ISO standard Recommended Practices Handbook

Owner ISO/TC 184/SC 4 Industrial data CAE-IF CAE-IF

Objective Provide information requirements and data model for AP209

Guide the implementation of AP209Provide semantics to AP209 data model

Facilitate understanding of AP209Accelerate implementation of the standard

Access Public CAE-IF members only or Public

CAE-IF members only or Public

Fee To buy Free Free

https://www.iso.org/standard/59780.html

https://www.cax-if.org/joint_testing_info.html





Live demo at NAFEMS World Congress 2019


Production-like model

Multiple AP209 translation tools

+ SFA tool

Demonstrate AP209 capabilities

implementedin CAE-IF test rounds Live demo @NWC19

Preparatory CAE-IF test rounds based on STEP AP209


Winglet spar FE model for live demo at NAFEMS 2019


Load case #4

Load case #3

STEP File Analyzer and Viewer (NIST)

2933 nodes2811 elements

Displacements case #4


Workflow for live demo of AP209-based data exchange


Interoperability

1 single STEP AP209 file Demo_interop.stpInput FEA data Results FEA data

NASTRAN to STEP (Jotne EPM translator)

1

NIST’s STEP File Analyzer

2

Regenerated Nastran FEA input and results

Input FEA data(regenerated)

Demo_regen.bdf

STEP to NASTRAN(CT Core translator)

3

NASTRANResults FEA data

(rerun)Demo_regen.pch

4Pre/post processor

5

Original Nastran FEA0

Original Nastran FEA input and results

Pre/post processorInput FEA data(original)

Demo_orig.bdf

Results FEA data(original)

Demo_orig.pch

screenshotscreenshot

screenshotscreenshots

NASTRAN

Compare Regenerated

FEA to Original FEA

6

Inboard front spar for winglet from the

CRYSTAL project


Conclusion§CAE interoperability based on international standards brings benefits to

industry§On the scope of FEA models and results, the implementation of STEP

AP209 in COTS products is now a reality§The collaboration between LOTAR EAS and the CAE-IF has been very fruitful:

§To continue the journey, we need you!


LOTAR EAS CAE-IF• Defines use cases• Defines test cases• Assigns priorities

• Organizes and runs interoperability test rounds


Thank you !

nFor question regarding LOTAR EAS please contact:[email protected]

nFor questions regarding the CAE Implementor Forum : [email protected]


mailto:[email protected]

mailto:[email protected]

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