Optimisation Based Composites Materials Characterization

Optimisation Based Composites Materials Characterization

EATC-2013

EATC - 2013 2


AMET

Development of a Software Tool to define the RADIOSS LAW_25

(CRASURV) Parameters from Experimental Test Data

EATC - 2013 3


AMET

Flux Diagram

user LAW_25 card (first guess)

HyperStudy

plot display LAW_25 card

FEM model – T45°

FEM model – C90°

FEM model –C0°

FEM model – T90°

FEM model – T0°

Test T-45°

Test C-90°

Test C-0°

Test T-90°

Test T-0°

MMG MMG

interpolation

+ … +

parameters extraction

MMG

HyperMesh

EATC - 2013 4


AMET

Step 1: Test Data Loading

EATC - 2013 5


AMET

Step 2: Test Curve Selection

Weighted Average

User Selection

EATC - 2013 6


AMET

Test Data Interpolation and Reconstruction

EATC - 2013 7


AMET


EATC - 2013 8


AMET

0.00

100.00

200.00

300.00

400.00

500.00

600.00

700.00

0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04 0.045

00-02

00-02-Tratto-elastico

Polin. int. 6° (R2=0,99955)

σ

ε

σy0

σmax

Eεmax

Wpl

Loading

Unloading

Wel

+ … +

Failure

Test data

Interp. data

Elastic


Parameters extraction (Phase 1)

Global parameters

Elastic Modulus E1; E2

Shear Modulus G12

For each test direction j

Yield Stress s jy0

Maximum Stress to Failure s jmax

Elongation at Failure e jmax

Maximum plastic work W jpmax

EATC - 2013 9


AMET

0

100

200

300

400

500

600

700

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00

σ

Wpl

σ = σ(Wpl)

σ (Wpl) test -polynomial

𝑙 𝑡𝑜𝑡

− 𝑒𝑙 𝑡𝑜𝑡

− −

2∙ − − −

2𝐸

𝑙

2𝐸− 𝑡𝑜𝑡

− ∙2

− −

σ

ε

σy

0.00

100.00

200.00

300.00

400.00

500.00

600.00

700.00

0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04

εy

2

4

E

n

3

1

Wel

σmax

εt

σ1

σ2

σ3

σ4

0 1 2 3 4 nn-1

σn

σ n-1

+ … +

For each test direction j

Stress as a function of

Plastic Work


Test Data as function of Plastic Work

EATC - 2013 10


AMET

Transformation of Test data in Exponential Form

Parameters extraction (Phase 2)

0

100

200

300

400

500

600

700

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00

σ

Wpl

σ (Wpl)

σ (Wpl) test - polynomial

σ (Wpl) test - exponential

0

100

200

300

400

500

600

700

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00

σ

Wpl

σ = σ(Wpl)

σ (Wpl) test -polynomial

Non linear optimisation algorithm

(best fit)

… For each test direction j

Hardening coefficient b j

Hardening exponent n j

EATC - 2013 11


AMET


HyperStudy


FEM model – T45°

FEM model – C90°

FEM model –C0°

FEM model – T90°

FEM model – T0°

Test T-45°

Test C-90°

Test C-0°

Test T-90°

Test T-0°

MMG MMG

interpolation

+ … +


MMG

HyperMesh

Flux Diagram

EATC - 2013 12


AMET

Step 3: First Guess LAW_25 Card Parameters

EATC - 2013 13


AMET

Step 4: Optimization Engine and Solver Choice

Up to now, only RADIOSS as solver and

HyperStudy as optimisation engine have

been implemented

EATC - 2013 14


AMET


HyperStudy


FEM model – T45°

FEM model – C90°

FEM model –C0°

FEM model – T90°

FEM model – T0°

Test T-45°

Test C-90°

Test C-0°

Test T-90°

Test T-0°

MMG MMG

interpolation

+ … +


MMG

HyperMesh

Flux Diagram

EATC - 2013 15


AMET

FE models – Property and BCs set-up

Five FE models (one for each test direction) are automatically generated based on

test data:

Dimension (L x W)

Thickness

Number of plies

Plies orientation

Boundary condition Property Card generation

BCs set-up

Constraint

(Ti;Ri=0)

(Ty, Tz =0)

(Tz =0)

Reference vector[1,0,0]

Imposed Velocity

EATC - 2013 16


AMET

Design Variables Set Up

Tension 0°

Tension 90°

Compression 0°

Compression 90 °

Tension 45°

Coefficients of the LAW_25 expression: sj0, b

j, nj

EATC - 2013 17


AMET

Optimisation Set Up

Response Function

For each test (1…5) a correlation function is defined …

𝐹(𝑅 ) ∗ 𝐺 − 𝑦𝑖 − 𝑦 𝑖

𝑖=

𝑦𝑖 − 𝑦

𝑖=

𝐾

=

𝑦𝑖= experimental data

𝑦 𝑖= numerical data

𝑦 = experimental data average

… and used as objective function for a System Identification Analysis.

EATC - 2013 18


AMET


HyperStudy


FEM model – T45°

FEM model – C90°

FEM model –C0°

FEM model – T90°

FEM model – T0°

Test T-45°

Test C-90°

Test C-0°

Test T-90°

Test T-0°

MMG MMG

interpolation

+ … +


MMG

HyperMesh

Flux Diagram

EATC - 2013 19


AMET

Optimisation Set Up

HyperStudy XML file generation (batch mode):

Design Variables

EATC - 2013 20


AMET


Design Variables Links

Optimisation Set Up

EATC - 2013 21


AMET


Responses

Optimisation Set Up

EATC - 2013 22


AMET


Optimisation Analysis Type and Parameters

Optimisation Set Up

EATC - 2013 23


AMET


HyperStudy


FEM model – T45°

FEM model – C90°

FEM model –C0°

FEM model – T90°

FEM model – T0°

Test T-45°

Test C-90°

Test C-0°

Test T-90°

Test T-0°

MMG MMG

interpolation

+ … +


MMG

HyperMesh

Flux Diagram

EATC - 2013 24


AMET

Step 5: Data Fit Check

EATC - 2013 25


AMET


EATC - 2013 26


AMET


EATC - 2013 27


AMET


EATC - 2013 28


AMET


EATC - 2013 29


AMET

Step 6: LAW_25 Card Export

EATC - 2013 30


AMET

Concluding Remarks

The tool is today at a prototype stage, logics are fully implemented, links with

Hyperstudy and Hypermesh to allow batch mode running has to be improved.

The goal of helping the user to compile the RADIOSS LAW_25 CRASURV

formulation is fully achieved; the complete loop lasts less than two hours.

In the next future the tool features will be extended to RADIOSS LAW_25 Tsai-Wu

formulation and to LS-Dyna MAT_22, MAT_58 and MAT_59 material laws.

EATC - 2013 31


AMET

Thank You!

Michele Rabito

[email protected]

Date post:	14-Jul-2015
Category:	Technology
Upload:	altair-engineering
View:	427 times
Download:	7 times

Optimisation Based Composites Materials Characterization

Technology