advanced design, analysis and optimization of composite structures

Innovation Intelligence®

Advanced Design, Analysis and Optimization

of Composite Structures

ATCx Houston

October 8th, 2015

Warren DiasBusiness Development Manager

Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.

Agenda

Design, Analysis and Optimization of …

Laminate Composites

Micromechanical Enhancement

Multiscale Systems


HyperWorks Past, Present and FutureH

yp

erW

ork

s

v1

4+

Manufacturing Simulations Draping, Forming, Curing

Moldflow | FiberSim | ESI

HyperMeshModern Ply Based

Composites Pre-Processing

VisualizationsVisually Verify the Model

OptiStructComposites Design

Optimization

HyperViewComposites Post-Processing

and Failure Analysis

Macro Solver

Multiscale Engine

Micro Solver

Mechanical, multiphysics, fatigue,

uncertainty quantification

Nastran | Abaqus | LS-DYNA

RADIOSS + OPTISTRUCT


Composites Design Process Overview

• Ply based modeling approach

• Incorporate manufacturing requirements

• Preserve ply book rules

Number of Plies

Ply Bundle Sizing

Phase 2

Laminate Stacking

Stacking Sequence Optimization

Phase 3

Rule based

ply shuffling

45 -45 0 0 0

45 -45 45 90

90 -45 45 -45 0 0

-45 90 45

(a) Ply Level (b) Superply Level

45 -45 0 0 0

45 -45 45 90

90 -45 45 -45 0 0

-45 90 45

(a) Ply Level (b) Superply Level

Ply Shapes

Free Sizing

Phase 1

x

y

z


Design and Optimization of Composite Material

Initial Design

Final Design

Composite Free-Size OptimizationWhat are the most efficient ply shapes?

Composite Size OptimizationHow many plies of each ply shape to meet engineering targets?

Composite ShufflingWhat is the exact stacking sequence to meet

manufacturing requirements?

Ply SlicingDetermines ply shapes


Underbelly Fairing Optimization

Aircraft underbelly

fairing

Model

Representation

Composite free

size optimization

– optimized ply

shapes

Ply shape

interpretation

Ply sizing optimization –

optimized ply thicknessesPly stacking sequence

optimization


Buckling load cases by 10% & deflection improved by

more than 35% without increase in overall weight


Metal vs. “Black Aluminum” vs. Composite

• Compliance = 5.15e+05

• Mass = 215 kg


• Mass = 184 kg

• Mass Savings: 14%

(w.r.t. Baseline)


• Mass = 146 kg


(w.r.t. Black Aluminum)


(w.r.t. Baseline)


Agenda


Laminate Composites


Multiscale Systems


Micromechanical Enhancement of Ply-level Results

• Multi-continuum phase average theory (for stress)

TTM fff }{}{][}{ TTM mmm }{}{][}{

Average

Fiber Stress

Enhanced

Ply Stress

Mechanical Stress in

the Fiber and

Thermal Effects due

to Ply Orientation

CTE Mismatch

Thermal

Fiber Stress

Thermal Effects in

the Fiber due to

Fiber/Matrix CTE

Mismatch

*Can not obtain

from FEA

=

=

+

+ Average

Matrix Stress

Enhanced

Ply Stress

Mechanical Stress in

the Matrix and

Thermal Effects due

to Ply Orientation

CTE Mismatch

Thermal

Matrix Stress

Thermal Effects in

the Matrix due to

Fiber/Matrix CTE

Mismatch

*Can not obtain

from FEA

= +

= +


Micromechanical Enhancement of Ply-level Results

Ply level design

Micromechanically

enhanced design

OHT-TL-OO-PLY

Optimized Stacking Sequence [−45a/0a/45a/90a/0c/90c/03d/90c/02

d/0a]s

Optimized Laminate Thickness n/a

Optimized Mass 0.056 kg (0.123 lbs)

OHT-TL-OO-MME

Optimized Stacking Sequence [−45a/0a/45a/90a/−45d/02c/45d/90c/0d/0b]s

Optimized Laminate Thickness n/a

Optimized Mass 0.053 kg (0.118 lbs)

0o Ply Shapes 90o Ply Shapes 45o Ply Shapes −45o Ply Shapes

0o Ply Shapes 90o Ply Shapes 45o Ply Shapes −45o Ply Shapes


Agenda


Laminate Composites


Multiscale Systems


Multiscale Systems

Scale 1

Fiber/Matrix

Scale 2

UD ply

Scale 3

Laminate

Scale 0

Constituent microstructure

Scale 1

Homogenized metal

Scale 0

Constituent microstructure


Why Multiscale Design and Analysis?

𝜎 𝑝𝑙𝑦

𝜎 𝑓𝑖𝑏𝑒𝑟

𝜎 𝑚𝑎𝑡𝑟𝑖𝑥

𝐸 𝑝𝑙𝑦

𝐸 𝑓𝑖𝑏𝑒𝑟

𝐸 𝑚𝑎𝑡𝑟𝑖𝑥

Scale 2 – Ply

Scale 1 – Fiber/Matrix

• Laminate scale – scale 3

• Laminate material properties

• Laminate stresses

• Laminate allowables

• Ply scale – scale 2

• Ply material properties

• Ply stresses

• Ply allowables

Multiscale methods: accurately predict material behavior

• Fiber/matrix scale – scale 1

• Constituent properties

• Constituent stresses

• Ply/constituent allowables

• Modeling at scale 1 is prohibitive!


Multiscale Methods with MDS Mechanical

Unit cell model definition

Linear material characterization

• Forward

• Inverse

Reduced order model

computation

Nonlinear material

characterization

Macro solver interface

Linear

Region

Nonlinear

Region

Damage Law Ultimate

Failure

Strain

Str

ess


Multiscale Design and Optimization

Thank You!