Virtual Designing using Topology Optimizationcae-forum.de/sites/default/files/FE-Design_Posess.pdf-...

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Example: F1 application - McLaren Racing LtdFinal validation

using field

testing

Axial loadTarget: 2.75mm

Torsional momentTarget: 0.141rad

Bending momentTarget: 0.034rad

Mx

My

Fz

Optimized

design for

minimum weight

Determine

material

distribution

External

flux

Iteration 1 Iteration 3 Iteration 6

Iteration 10 Iteration 20 Final Iteration

Initial

Optimized

Temperature

distribution

hotspots removed

Fluid Topology optimization- Minimize pressure drop - Design variables: porosity

Example: Inlet for Heat Exchanger

Design

domain

New Design

Cross sectional velocity and heat exchanger efficiency

Transfer

efficiency

+ 45%

Pressure

Drop - 46 %

Turbulent

stationary

flow

Virtual Designing using Topology Optimization

Iterative design

process using

rigorously calculated

sensitivities:

Design domain

with boundaries

Stiffer and lighter design

Advantages:

! New conceptual designs

! Faster development cycles

! Optimization implementation using

existing software for the “virtual”

equilibrium

! Support e.g. non-linear modeling:

- Contact

- Large deformation

- Non-linear materials

OptimizationOptimization

New material

distribution

PreprocessingPreprocessing

EquilibriumEquilibrium

Results

Optimization

loop

Finite element

solver:

- Abaqus

- Ansys

- Msc Nastran

- NX Nastran

CFD-solver:

- Fluent

- STAR-CD

Material design variables: ρ (thousands!!!)

Equilibrium: (high CPU-time)

Optimization - Derivatives using adjoint method:

(low CPU-time → free !!!)

{ }{ }

{ }{ }

{ } { }ρ

λρ

θθλ

∂=!

∂−=

∂ R

d

d

uu

R T

Finish

{ } { }0=R

..........................................

Structural Topology Optimization

- Minimize mass, Maximize stiffness, eigenfrequencies, etc.

- Design variables: Young modulus, density, non-linear constitutive material

laws e.g. plastic materials.

Example: JCB Tractor Lift Mechanism

a)

c)

!!

!!b)

!!

DesignDesign

domaindomain

Twice stiffness of new

design compared to old

design for equal mass

a) Setting up the model in CAD and exporting model to CAE.

b) Automated conceptual topological design process including manufacturing constraints.

c) Transferring the optimized structure back into the CAD system using smoothed iso-surfaces.

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……………………………………………………Thermal Topology Optimization- Minimize temperature, etc. - Design variables: conduction and convection

......................................................................

……………………………………………………Claus B.W. Pedersen

claus.pedersen@fe-design.com

FE-DESIGN GmbH

http://www.fe-design.com

Telephone: +49 40 1814695 - 90

Concept of Topology Optimization

Determining material distribution ρ:

ρ~1 solid and ρ~0 void

5th optimization

iteration

10th optimization

iteration

15th optimization

iteration

25th optimization

iteration

Final – 33rd

optimization iteration

Topology

optimization

Verification

New CAD design

Design domain

Enforce 120° symmetry

Manufacturing constraints

Feasible

design

Infeasible

design

Loads

Wind turbine hub

Example: Renewable energy – a hub