Connection Elements for Joint Representation
-
Upload
altair-engineering -
Category
Engineering
-
view
272 -
download
6
description
Transcript of Connection Elements for Joint Representation
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
N. Pasligh (Presenter), R. Schilling
Crash CAE:Connection elements for joint representation exemplarily spot welds
Crash CAE:Connection elements for joint representation exemplarily spot welds
6/11/20142
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Motivation
6/11/20143
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Generic b-pillar high overloading crash example
� Force displacement chart
a) Perfect world scenario without failure
b) Joint pattern #1 and failure consideration
c) Joint pattern #2 and failure consideration
d) No connection between b-pillar and side
structure
e) Sheet metal + joint failure with joint pattern #1
Joint failure need to be considered
� Reliability required
Displacement
Fo
rce
[%
of n
o f
ailu
re]
Generic example:
� Extreme overloading
� Simple CAE model (no trim)
� Coarse mesh
� Simplified sheet metal and spot weld
data
a
e
c
d
b
� Side structure and b-pillar
6/11/20144
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Content
� Joint requirements
� Full vehicle CAE models
� History
� Joint environment
� Physical connections
� CAE connections
� Radioss solution and model approach
� Examples
6/11/20145
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Joint requirements
6/11/20146
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
General joint requirements
� Automatic joint creation based on push button principle for different detail levels
� Full integration into HyperMesh, HyperCrash required
� Correlation between physical and numerical characteristics� Good theoretical approach for RADIOSS solver
� Tension, compression, shear, bending, torsional and mixed behavior treatment (load level, energy consumption, …)
� 3 to 4 sheet connection treatment
� Automatic post-processing in HyperView required � e. g. percentage to failure - tension, shear, mixed,
angle of mixed loading, current loading condition, …
Pre-processing
Processing
Post-processing
6/11/20147
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Full vehicle CAE models
6/11/20148
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Full vehicle model history
Past Future
Past model:
� Mesh size > 50 mm
� 30,000 elements
� No/ basic joint modelling
� …
Today’s model:
� Mesh size ~ 5 mm
� 2 - 5 million elements
� Joint modeling
� Implemented joint failure
criteria
� …
Future model:
� Mesh size > 1 mm
� Multi million elements
� More detailed joint modeling
� Complex, interactive failure
criteria
� …
M o d e l c o m p l e x i t y
6/11/20149
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Examples of physical joining methods
Others
• Thermal (Laser
welding, brazing, …)
• Mechanical (Riveting,
screwing, …)
Example:
Spot welding Bonding
6/11/201410
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Full vehicle joint environment
Detailed FEM-model
� Time step too small
� Millions of elements for joints
���� not applicable to full car CAE
model
Extracted mid surfaces
� Time step as full car model
� Few additional elements
���� Applicable for full car CAE
Transfer to full vehicle
6/11/201411
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Type of joints
Common nodes Contacts Elements
1-D 2-D 3-D
Surface to surface
6/11/201412
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
RADIOSS solution and model approach
6/11/201413
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
x
y
z
σσσσxx
σσσσyy
ττττyx
ττττyz
ττττxy
ττττxz
Node 1 Node 2
Node 3
Node 5
Node 7Node 8
5.0 mm
Single 3-D joint element
shell
shell
Solid
H
• Considered element strength calculated
at integration points of mid surface
• Reference plane: mid surface with 4
integration points
• Element
height “H” can be zero
• Artificial
definition possible
� Connection methodology to connect shell mid surface layer
� Most important internal forces are considered at four integration points (allows
splitting forces into momentums)
� Element formulation is time step independent
σσσσzz
ττττzx
ττττzy
σσσσzz
ττττzx
ττττzy
Node 6
Continuum solid Cohesive solidvs.
3-D joint element example
� Details of 3-D element treatment
6/11/201414
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
� Modeling approach by cohesive /MAT/LAW59/ formulation in Radioss
/MAT/LAW59/59Connection element - D U M M Y -# Init. dens.
7.65E-6# E G
10.0 123.4# Nfunc Fsmooth Fcut Y_flag
1 1 0 0# Y_Func_N Y_Func_T Strain Rate ref. Yield stress Scale
1 2 0.00001 1/FAIL/CONNECT/59# EPS_N_MAX EXP_N ALPHA_N SR_N IFAIL ISOLID ISYM
1.0 2 1 0 1 1 1# EPS_T_MAX EXP_T ALPHA_T SR_T
10.0 2 1 0# EI_MAX
0/PROP/CONNECT/59Adhesive#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|/FUNCT/1Tensile curve# X Y
0 1.0000 1.0 1.0000
/FUNCT/2Shear curve# X Y
0 1.000 10.0 2.000
Shape parameter
Tensile strength vs. displacement
Shear strength vs. displacement
Failure displ.
Modulus data
Tension (mode I) Shear (mode II)
Joint material card
6/11/201415
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
� *1.rad file setting for MAT/LAW59
� /ANIM/BRICK/USR - variable settings for displacement based failure criteria
/ANIM/BRICK/USR3/1
/ANIM/BRICK/USR3/1
/ANIM/BRICK/USR5/1
Source: Altair Engineering GmbH, 2013
Joint post-processing
Tension (mode I) Shear (mode II)
6/11/201416
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Joint material card modification
� Characterization of spot welds for full vehicle models
Shear load
Width = 0.5 “h”
He
igh
t “h
”
Ftension = 2 * Fshear
Width = “h”
Ftension = Fshear
Width = 1.5 “h”
Ftension = 0.67 * Fshear
Shear load Shear load
� True thickness flag � compensation of mesh dependent momentums
Re
su
ltin
g te
nsio
n lo
ad
6/11/201417
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
� Improvement of mixed mode treatment
Joint material card update ���� MAT/LAW83
30
°
60
°
α=1
α=0.1
α=-2α=-10
Influence of alpha parameter Influence of beta parameter
Source: V. Dampuré: Altair Engineering GmbH, 2014
6/11/201418
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Meshing of joints
� Meshing proposals CAE
5.0 mm
Source: Altair Engineering GmbH, 2011
6/11/201419
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Examples
6/11/201420
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
CAE design development support
Physical joining Full vehicle test
Validation: ComponentCalibration: Coupon Validation: Sub-system
5.0 mm
CAE concept Product development
6/11/201421
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
� Load case
Validation component
� CAE model
� Results
� Force-displacement chart of a component test example
Adhesive
Spot weld
6/11/201422
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Validation sub-system
� CAE model� Load case
� Results
Adhesive
Spot weld
� Force-displacement chart of a sub-system test example
6/11/201423
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Product development: Pre-processing
� Generation of joints
Pre-processingE. g. Fiesta � single parts
Source:
A. Hänschke
Source:
U. FoxScrew
Spot weld
Automatic model assembly
6/11/201424
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
� Full vehicle load case: examples
Processing
Product development: CAE crash analysis
Post-processing
6/11/201425
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Summary
� Efficient pre-processing tools needed
� More efficient integration and fully automatic pre-processing
� Solve 3T and 4T dependency for multi layer joints
� Stable connection solving algorithm
� Stabilize element deletion and energy release rate handling
� Mixed load handling, joint interaction and mid surface gap treatment
� Fully supported and automatic visual/ tabulated/ … inspection of joints by post-processing tools
Connection elements are for developing a reliable crash CAE design
Thanks to Altair team for support! Special thanks to M. Bulla and V. Dampuré.
6/11/201426
© 2014 Ford Motor Company, All Rights Reserved
7th European Altair Technology Conference , June 24th - 26th 2014, MunichDr. Niels Pasligh (R&A Europe AMCAE), Dr. Robert Schilling (FoE)
Thank you very much for your attention!