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GENOA and Hyperworks Integration for Advance Composite Product Design and Analysis

Frank Abdi , Anil Mehta, Harsh Baid, Cody Godines AlphaSTAR Corporation, Long Beach, CA, USA

and Robert Yancey, Harold Thomas

ALTAIR Engineering Inc., Irvine, CA

Altair Conference

May 5-7 2015 Detroit Michigan

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Outline • AlphaSTAR

• Methodology – De-homogenized-Multi-Scale Modeling

– Progressive Failure Dynamic Analysis

– Progressive Failure Static Analysis

• Case Studies – RADIOSS: Numerical Simulations of Composite Tubes

– OPTISTRUCT: • Lap Shear Damage Mode evolution and Propagation

• Optimization of Storage Tank shape (composite overwrapped Pressure Vessel)

• HMMWV Suspension System

• Summary & Conclusions

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AlphaSTAR Corporation (ASC) • Founded in 1989 - Headquartered in Long Beach, Ca/Rome, Italy

Mission Provide physics based composites simulation solutions and software

Service industry and government for advanced composite parts/systems

Focus composites structural design and advanced simulation including: composites, metals, ceramics, polymer, hybrid

Industry Validated Software Aerospace: Commercial aircraft Certification by Analysis with Reduced Tests Automotive: Racing cars, Hydrogen Tank Infrastructure: Bridge, Wind & Energy

Long Beach, CA

Rome, IT

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GENOA Composite Multi-Scale Modeling Computational Tool Predict Test and Consider Uncertainties & Defects

MATERIAL CLASS • Fiber reinforced polymer composites (Chopped, Continuous)

o Thermoset o Themo-plastic o Elastomer

• Metals o Fracture Toughness o Fatigue Crack Growth

• Hybrid Composites (Glare) • Ceramics • Nano composites

Application product • Continuous fiber (MCQ-composite) • Chopped fiber (MCQ-chopped) • Ceramics (MCQ-ceramics) • Nano composites (MCQ-nano)

Manufacture Processes Application product

• Filament winding (GENOA GUI) • Resin Transfer Molding (GENOA GUI)

Durability Damage Tolerance/Reliability

Application product • GENOA running FE (GENOA Suite *) • GENOA as subroutine (GENOA (V)UMAT)

ABAQUS (V)UMAT Environment Damage Evolution

Integrated MCQ and automatic UMAT generation as CAE-plugin

Damage Location Ply damage visualization

Failure mode and index

* WWFE I-III Round Robin 1991, 1998, 2013 Journal of Composite Materials, Aug 2013, F Abdi, M Garg, et al.

Product line

Material Characterization & Qualification (MCQ)

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De-Homogenized vs. Homogenized Approach

•Chopped Fiber-Elastomer: Galib H. Abumeri, M. Lee, “A Computational Simulation System for Predicting Performance of Chopped Fibers Reinforced Polymer Composites”. ERMR-2006-Elastomer-Reno Filename: a) 7-06_Abumeri-Paper-ERMR2006.doc; b) 7-06_Presentation-Abumeri-chopped-fiber-ERMR2006.pdf

Schematic View of De-Homogenized vs. Homogenized

• Multi-Scale Modeling of composite constituents • fiber, matrix, and interface

• Manufacturing Effect of Defects • fiber waviness, agglomeration, interphase, • resin rich, void shape/size

• Fiber angle orientation Through-thickness

• Design Parameters Saturation on stiffness/ strength : •fiber length (limitation using homogenized method) •fiber shape

Multi-Scale Nano-micro Damage mechanics:

De-homogenization Modeling Approach De-Homogenization Homogenization

* Courtesy of www.mscsoftware.com* Courtesy of www.mscsoftware.com

Architecture Homogenized

De-Homogenization Homogenization

* Courtesy of www.mscsoftware.com* Courtesy of www.mscsoftware.com

Architecture Homogenized

De-Homogenization Homogenization

* Courtesy of www.mscsoftware.com* Courtesy of www.mscsoftware.com

Architecture Homogenized

Homogenization

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Progressive Failure Dynamic Analysis

• Perform explicit FE analysis at a specified time step • stress and strain distributions and deformation shape • Stress and strain calculations in each ply • Stress and strain calculation in micro-level

• Estimate damage in different length scales • Ply level failure surface • Constituent level (fiber-matrix) failure surface – micromechanical approach

• Check convergence criteria • Number of damaged plies (ply level damage) • Number of fractured elements (total laminate damage).

• Update the stiffness properties of damaged elements • Proceed to the next time step/iteration (restart)

Procedure of Explicit Finite Element Framework

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GENOA Platform

1. UMAT+ GUI Plug In: Integrated with ABAQUS (implicit/explicit), RADIOSS, ANSYS FEA 2. GENOA-MS-PFA: Uses FE solvers as subroutine: (OPTISTRUCT, ABAQUS, LSDYNA, NASTRAN) 3. Damage/Fracture Evolution: GENOA GUI

GENOA

Abaqus Radioss Ansys

GENOA

Optistruct

* ABAQUS, Optistruct, LSDYNA, ANSYS, NASTRAN and MHOST

GENOA is an augmentation to FEA software with 2 Options + pre/ post

UMAT+GENOA GUI

GENOA with ALL FEA*

Radios UMAT Environment

Damage Evolution

Damage Index

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Technical Approach: Damage & Fracture Evolution Delamination Regions (Overlap Damage/Fracture)

Fracture Mechanics Delamination Damage Mechanics Delamination Type

ILT

ILS RROT

Simulation Process • STEP 1: Simulate the problem with PFA (Stage1-5)

• Estimate damage accumulation in FE model • Predict damage and failure initiation and damage propagation • Predict crack path

• STEP 2: Simulate with VCCT/DCZM (Stage 3-5) • Prepare a coarser FE model again with pre-defined crack path

(predicted via PFA simulation or test) • Simulate and predict complete damage and failure process

(damage initiation and propagation, crack initiation and propagation and final failure) of the component

• DCZM combined with PFA to account for damage accumulation for improved predictions

• STEP 3: combined PFA+VCCT/DCZM (Stage 1-5)

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PFA takes full-scale FEM and breaks material properties down to microscopic level. Material properties are updated, reflecting any changes resulting from damage or crack

In-Depth Evaluation of Multi-scale Process

Vehicle Component Laminate 3D Fiber, Weave, Stitch

Lamina 2D Woven

Decomposition Traditional FEM Stops Here GENOA goes down to micro scale

Unit cell At node or element depending on solver

Sliced Unit Cell Micro Scale

FEM results decomposed to micro scale

Reduced properties propagate up to vehicle scale

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*Options: Tsai-Wu, Tsai-Hill, Hashin, User defined criteria, Puck, SIFT, **Honeycomb: Wrinkling, Crimpling, Dimpling, Intra-cell buckling, Core crushing. *** Environmental: Recession, Oxidation (Global, Discrete), aging, creep

Ref: C. Chamis, F. Abdi, M. Garg, L. Minnetyan, H. Baid, D. Huang, J.Housner, F. Talagani,” Micromechanics-based progressive failure analysis prediction for WWFE-III composite coupon test cases”. Journal of Composite Materials Part A 47(20–21) 2695–2712, 2013

Damage, and Fracture Mechanics based

Unit Cell damage criteria

Delam criteria

MATRIX 1. Micro crack Density (TT) ,LT 2. Matrix: Transverse tension 3. Matrix: Transverse compression 4. Matrix: In-plane shear (+) 5. Matrix: In-plane shear (-) 6. Matrix: Normal compression

FIBER 7. Fiber: Longitudinal tension 8. Fiber: Longitudinal compression 9. Fiber Probabilistic 10.Fiber micro buckling 11.Fiber crushing 12.Delamination

DELAMINATION 15. Normal tension 16. Transverse out-of-plane shear (+) 17. Transverse out-of-plane-shear (-) 18. Longitudinal out-of-plane shear (+) 19. Longitudinal out-of-plane shear (-) 20. Relative rotation criteria 21. Edge Effect

13.Strain limit

FRACTURE 22. LEFM :VCCT (2d/3d) 23. Cohesive: DCZM (2d/3d)

24. Honeycomb** 25. Environmental***

14. INTERACTION* • MDE (stress) or SIFT (strain)

Multi-Scale Multi Failure Criteria

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• Good agreement between the deformation mode from experiment and simulation

• Similar deformation mode approves the energy absorption mechanism observed in the experiment.

Crush Tubes Progressive Damage Analysis

Deformations from Experiment

Deformations from Simulation

Progressive damage analysis used to Simulate crush tubes

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Energy Absorption Characteristics

• Crush load versus crush distance as a measure of energy absorption • Tape composite systems considered • Serrations arise as a result of the stick-slip nature of crushing mechanism • required stress to initiate microcracks and damage are higher than those for propagation • Higher second peak observed

Crush load versus crush distance of tape laminate with the layup of [45/0/-45/0/-45/0/45]

Damage Index Table

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Cru

sh F

orce

(Nor

mal

ized

)

Crush Displacement (Normalized)

TEST 1TEST 2TEST 3GENOA PFA + MDNASTRAN

GENOA+RADIOSS: Good Agreement Between Test and Simulation

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Damage Evolution Distribution During Crushing Process Fiber Longitudinal compressive failure (11C)

Crush Distance

Δ=15 mm (1.88%*)

Δ=40 mm (5.00%*)

Δ=80 mm (10.00%*)

Δ=350 mm (43.75%*)

Def

rom

ati

on S

tate

Ply 1

Ply 2

Ply 3

Ply 4

Ply 5

Ply 6

Ply 7

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Chopped Fiber Composite: Crush Modeling Process Determine Ply Angle Through Thickness – De-Homogenization Approach

Shell Model – Low Fidelity

Orientation Data Moldex3D Model 2 mm Laminate PART Orientation Tensor Mapping

• Material Characterization • Mapping from Un- structured mesh to structured mesh using orientation tensor • De-Homoginization Process: Determine Chopped fiber orientation through-the-thickness • Multi-Scale damage assessment by Progressive Failure Analysis:

Mapping (un-structured to Structured/solid)

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Validation: Chopped Fiber Composite Characterization Simulation Vs. Coupon Tests (PBT-GF20)

Flow, Cross Flow, Shear (Stress-Strain)

0.00.10.20.30.40.50.60.70.80.91.0

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Orie

ntat

ion

Normalized Thickness [z/H]

Test-A11 Test-A22 Test-A33MCQ-A11 MCQ-A22 MCQ-A33

Orientation Distribution Vs. Test

3 point Bending Coupon Analysis

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 2 4 6 8 10N

orm

aliz

ed L

oad

Displacement [mm]

Flow-Test Cross-Flow-TestFlow-MCQ-GENOA Cross-Flow-MCQ-GENOA

Flow, Cross Flow (L-D Curves) Through-thickness

damage

Ref: H.K. Baid, F. Abdi, M. C. Lee, Uday Vaidya, “Chopped Fiber Composite Progressive Failure Model under Service Loadin”,SAMPE 2015

0.00 0.01 0.02 0.03 0.04

Strain [mm/mm]

Stre

ss [M

Pa]

Test-Flow Test-45-Deg Test-Cross-FlowMCQ-Flow MCQ-45-Deg MCQ-Cross-Flow

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Chopped Fiber Crush Tube Analysis Ac

celer

ation

(m/s2

)

Time (s)

Test

De-homogenized

Load Displacement Curves

10 (ms) 20 (ms)

30 (ms) 40 (ms)

Deformation Vs. Time

Acceleration Vs. Time

Explicit chopped fiber crush tube simulation

Norm

alize

d Loa

d

Displacement

TESTDe-Homogenized

Simulation results matches well with test

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Effect of Weak Interphase & Agglomeration Effect of Defects

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

Baseline Interphase Agglomeration

You

ng'

s M

od

ulu

s [G

Pa]

0

50

100

150

200

250

300

350

Baseline Interphase AgglomerationSt

ren

gth

[MP

a]

Tensile StrengthCompressive StrengthShear Strength

Nano-comp: Mohit Garg, F. Abdi, J. Housner, “PREDICTION OF EFFECT OF WAVINESS, INTERFACIAL BONDING AND AGGLOMERATION OF CARBON NANOTUBES ON THEIR POLYMER COMPOSITES ”. SAMPE- Conference, Longbeach, Ca-may2013.

Predicted modulus, tensile, compressive and shear strengths for the 3D randomly oriented MWCNTs in epoxy; baseline; baseline with interphase of 1 nm thickness and baseline with agglomeration (no

interphase); amplitude (a) = 0.0 to 700.0 nm

Modulus Effect Strength Effect

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Experiments – Modified Thick Lap Shear Test

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• ASTM standard D5656 test • The film adhesive bondline

thickness are 0.01” – 0.03” Modified ASTM D5656 - Thick Lap shear Test

* A modified extensometer is implemented to improve strain measurement

A modified biaxial extensometer allows accurate measurement

Test Shows Adhesive Failure

Test and analysis average shear stress-strain curve ASTM D5656

Ref: Yibin Xue, Frank Abdi, Suresh Keshavanarayana, and Waruna Senevirantne, “Physics-based modeling and progressive failure and probabilistic sensitivity analysis for adhesively bonded structural components, ”, 10th International Conference On Durability Of Composite Systems, September 16-18, Brussels Belgium

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Multi-Scale Material Modeling

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Assumed Reverse Engineered Effective Matrix Equivalent SS Curve from MCQ Composites Material Library

0

20

40

60

80

100

120

140

0.00 0.10 0.20 0.30

Stre

ss [M

Pa]

Strain [mm/mm]

Effective Equivalent Matrix SS Curve

Effective Matrix Equivalent SS Curve Bond Properties (PU-1340)

0

10

20

30

40

50

60

70

0.00 0.01 0.02 0.03 0.04

Str

ess

[MP

a]

Strain [mm/mm]

PU-1340 SS Curve (Engineering)

Test

Bond Test (Mechanical Properties) Bond Test (Strain)

PU-1340Strain Limit Value

Eps11T 3.147E-02Eps22T 3.147E-02Eps33T 3.147E-02

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Results: Load Displacement Curve FE Model Damage Progression Events & Failure Modes

B

C

E

A

D

F Normal tension [Eps33T]

All Damage All Damage

Transverse Out-plane Shear strain [Eps23S]

Longitudinal Compression Strength [S11C]

Normal tension Strain[Eps33T] Final Damage

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6

Load

(N)

Displacement (mm)

Test

MS-PFA A

B

C D

E

F

Ref: S. DorMohammadi, F. Abdi, C.Godines, R. Yancey, H. Thomas, " Zig-Zag Crack Growth Behavior of Adhesively Bonded Lap shear specimen", SAMPE/CAMX Oct, 2014,. Orlando Floida

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Hybrid Suspension Damage

Fracture of Upper Control Arm At Ultimate Load

Damage/Fracture Modes

Steel

Steel

Damage Initiates in Steel in Upper Control Arm Fractured Suspension Unit

Damage Evolution Under Static Loading

Reference: G. Abumeri, B. K. Knouff, D. Lamb, D. Hudak, and R. Graybill, “BENEFITS OF HIGH PERFORMANCE COMPUTING IN THE DESIGN OF LIGHTWEIGHT ARMY VEHICLE COMPONENTS”, Presented ArmyScienceCOnference-Nov2010, Orlando, FL

Improved L-D curve

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Failure Locations

Spring Support

Upper Control Arm

Lower Control Arm

Spindle is Damaged because of modeling constraints

GENOA Predicted Damage Under Fatigue Spectrum Cycling Loading

Ref: G. Abumeri, M. Garg, D. Lamb, “Technical Approach for Coupled Reliability-Durability Assessment of Army Vehicle Sub-Assemblies ”. SAE World Congress, 2008, 08M-126, Detroit Mi, April 2008.

HMMWV: Durability of double A-arm suspension

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3D printing process introduces significant thermal loading in structure 3D-Printing BAAM

•Thermoplastic resin (ABS) reinforced with chopped carbon fiber is placed while hot and not fully solidified. Layer by layer (beads) the 3D structure is produced.

Cross section of two beads

Robot printer head Delamination

Thermo-graphical image of the printing process

Printing process

•Temperature difference and cohesion between the individual beads,

• results in asymmetric shrinkage, • bending moments introduced in structure

V. Kunc, B. Compton, S. Simunovic, C. Duty, L. Love, B. Post, C. Blue1, F. Talagani, R. Dutton, C. Godines, S. DorMohammadi, H. Baid, F. Abdi , “Modeling of Large Scale Reinforced Polymer Additive Manufacturing”, Anetc Conference Orlando Florida. March 23- 2015.

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Damage and fracture evolution analyzed in ~12 hrs

3D-Print –Strati Car

Delamination during simulation

Fracture evolution pattern

Production process simulation

Damage location and % of contributing failure mechanisms

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Approach: model generator; characterize chopped fiber; progressive damage/fracture analysis

3D-Print: Solution approach

Multiple solution strategies have been considered

Tensor orientation

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Delamination Initiation (P= 22.06 MPa)

Burst Initiation (P = 34.75 MPa)

Delamination Progression (P= 30.9 MPa)

Durability: Delamination Initiation / Progression and Fracture Simulation

Test

Test

Reliability: Predict scatter in failure load, ranking of random variables

Test Burst pressure: 33.72 to 36.56 MPa (Low-Fidelity Durability and Reliability)

20.7 27.6 34.5 41.4 48.3 55.2 [MPa]

Tank Storage Analysis/Validation

G. Abumeri, F. Abdi, M. Baker, M. Triplet and, J. Griffin “Reliability Based Design of Composite Over-Wrapped Tanks”. SAE World Congress, 2007, 07M-312, Detroit Mi, April 2007

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High Fidelity Validation US Army Optimized COPV Tank Failure process

Damage Initiation (3 Mpa)

50% pressure (15.5 MPa)

Fiber Failure (Final Burst) (31 MPa)

75% pressure (21.7 MPa)

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High Fidelity Validations: Optimized COPV Process of Shape Optimization and design dome parameter from

OPTISTRUCT

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Summary & Conclusions • MCQ performs material characterization and qualification including PFA.

• Virtual testing is made possible by conducting PFA and combining those results to predict structure/component safety based on physics and micro/macro mechanics of materials, manufacturing processes, available data, and service environments.

• The approach takes progressive damage and fracture processes into account and accurately assesses reliability and durability by predicting failure initiation and progression based on constituent material properties.

• Such approaches are becoming more widespread and economically advantageous in some applications

• Composite Multi-scale Modeling De-Homogenized Approach validated with test for various applications: (1) Crush tubes; (2) Lap-shear; (3) 3D printing; (4) Storage tank

• GENOA-PFA enabled the application of multi-scale progressive failure Dynamic criteria with ALTAIR products (RADIOSS and OPTISTRUCT).