Accurate Simulation of Short-Fiber-Reinforced Automotive Parts

Sascha Pazour

PART Engineering GmbHpazour@part-gmbh.de0049 2204 30677 26

© PART Engineering GmbH, www.part-gmbh.de

Cologne

Berlin

Frankfurt

Hamburg

Stuttgart

Munich

Wolfsburg

Ingolstadt

Rüsselsheim

• Founded in 1999 as FEM services supplier

• Focus on structural mechanics

• Mission is to provide CAE services and software in

order to add value to our customers‘ CAE chain

• 20 years experience in FEA

• 10 years experience in CAE software development

• Two software products by our own:

• Development partner of major CAE software vendors

Life

Bergisch

Gladbach

PART Engineering – Key Facts

Influence of Fiber Orientation onto Material Properties

Fig. 2

100 100

58

65

0

20

40

60

80

100

120

Stiffness Strength

in flow cross flow

100

350

0

50

100

150

200

250

300

350

400

therm. Expansion

material: PA6+GF30

Fiber Orientations in Short-Fiber-Reinforced Plastics

S1 Shear layer: Fibers oriented parallel to flow direction

S2 Mid layer: Fibers oriented perpendicular to flow direction

Fig. 3

Flow Direction X

X

Cut View XFlow Direction

S1

S2

S1

Example Micrograph Pictures:

Thick

Mid LayerThin

Mid Layer

Degree of Orientation

Fig. 4

33

2322

131211

..

.

a

aa

aaa

000

000

001

33.000

033.00

0033.0

2

31

general case unidirectional quasi-isotropic

-90° +90°-45° +45°0° -90° +90°-45° +45°0°-90° +90°-45° +45°0°

Schmelzeflussrichtung

Schmelzeflussrichtung

2

1

Material Complexity

Fig. 5

Thermo-Mechanical

Simulation

E

α

Young´s Modulus

Poisson´s Ratio

Coeff. of Lin. Therm. Exp.

z

yx

Fiber Orientation

(Local System)

Isotropic

Anisotropic

Temperature Dependant

Material Complexity

Fig. 6

z

yx

Fiber Orientation

(Local System)

(1/0/0)

(0,7/0,2/0,1) (0,5/0,5/0)

(0,33/0,33/0,33)

Degree of Orientation

(Fiber Distribution)

80°C23°C120°C-40°C

Temperature

x

y

z xy yzzx

Local Directions

Material Complexity

Fig. 7

xy

zx

y

E2

α2

x

E1

α1

z

E3

α3

G12 α1212

23°C

yz

G23

α23

23

G31

α31

31

Orthotropic Material ModelNeeds 15 lin.-elastic temp.

dependant material properties:

Coeff. of lin. Therm. Expan.:

α1, α1, α1, α12, α23, α13,

Tensile moduli: E1, E2, E3

Shear moduli: G12, G13, G23

Poisson ratios: 12, 13, 23

Example: Weld Lines

Isotropic ApproachFig. 8

Common Approach:

Isotropic

Schmelzeflussrichtung

Schmelzeflussrichtung

Example: Weld Lines

Anisotropic ApproachFig. 9

CONVERSE Approach:

Anisotropic

Schmelzeflussrichtung

Schmelzeflussrichtung

Fiber Orientation and Anisotropic Material

Fig. 10

Converse Graphical User Interface

[Part: Mann & Hummel]

Mesh Topology

Fig. 11

ConverseIM solver mechanical solver

shell (mid-plane/surface) => shell (tria, quad)

shell (mid-plane/surface) => solid (tet, hex)

solid => solid (tet, hex)

unequal meshes

possible

Fig. 12

Converse Features and Interfaces

Mechanical SolverInjection Moulding

Solver

- Moldex 3D

- Moldflow

- Cadmould

- Sigma

- Fluent

- Simpoe

- 3D Timon

- Optistruct

- femfat

- nCode

- Abaqus

- Ansys

- Marc

- Nastran

- LS-Dyna

Orientations

Pressures

Temperatures

Wall Thicknesses

Residual Stresses

Shrinkage & Warpage

Weldlines

0

200

400

600

800

1000

1200

1400

0 1 2 3 4 5 6

Kra

ft [N

]

Verschiebung [mm]

Messung 1

Messung 2

isotrop

orthotrop

Example: Rotary Valve

Material: Grivory HTV 3H1

forc

e [N

]

displacement [mm]

test 1

test 2

FEA isotropic

FEA anisotropic

Fig. 13

[Part: Mann & Hummel]

Example: Air Intake Manifold

Material: Ultramid A3WG6

Fig. 14

[Part: Mann & Hummel]

Eigenfrequencies and Eigenmodes

0

100

200

300

400

500

600

700

800

900

1000

250,00 270,00 290,00 310,00 330,00 350,00 370,00 390,00

eff

ektive M

asse

[g]

Frequenz [Hz]

x-Richtung - isotrop y-Richtung - isotrop z-Richtung - isotrop

x-Richtung - orthotrop y-Richtung - orthotrop z-Richtung - orthotrop

x-direction-isotropic

x-direction-anisotropic

y-direction-isotropic

y-direction-anisotropic

z-direction-isotropic

z-direction-anisotropic

frequency [Hz]

effe

ctive

ma

ss [kg

]

Fig. 15

[Part: Mann & Hummel]

Lens Bracket Example

Fig. 16

Part Geometry Fiber Orientation in Converse

[Valeo Lighting Systems]

Lens Bracket Example

Fig. 17

Frequency correlation – simulation to Xp. modal analysis

+5Hz

+30Hz

Converse

Isotropic

Average error – 4 Modes

Mode Experimental (Hz) Isotropic (Hz) Converse (Hz)

1 44 76 60

2 56 77 62

3 91 114 94

4 224 270 218[Valeo Lighting Systems]

Example: Burst Pressure

Material: PP + GF20

Fig. 18

Influence Of Production on Fiber Orientation

Fig. 19

Supplier 2Supplier 1

• Two suppliers but parts are geometrically up to 95% equal.

• Same material supplier, same mashine settings, etc.

• Different gating location means two completly different engine components!

Water pump housing

Gate location

Gate location

Moldflow results show different orientation

Influence Of Production on Anisotropic Part Stiffness

Fig. 20

Blue – Supplier 1

Red – Supplier 2

Dotted – Isotropic material

fiber orientation and material model by

4. isotropic vs. anisotropic results

∆ - 62%

Untolerable error if homogeneous

isotropic material is used!

3. displacements

1. distributed pressure on sealing contact surface

2. results evaluated on a path

Dis

pla

ce

me

nt

True distance along path

Fig. 21

www.part-gmbh.de What´s New?

Converse Installation

Fig. 22

Add Value to Your Mechanical Simulation

consider the real part properties

get better predictions of

strength & deformation

by using data already

available

Thank you for your attention!

Please don´t hesitate to ask a question!