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Short Introduction to LS-DYNA and LS-PrePost

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Short Introduction to LS-DYNA and LS-PrePost
Jimmy Forsberg

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Content
�� DYNAmore Nordic presentation �� Introduction to LS-DYNA
�� General work with different solvers. �� LS-DYNA capabilities �� Keywordfile structure
�� Introduction to LS-PrePost
�� Layout �� Pre-processing �� Post-processing �� Special features
�� Composite tool
2013-09-09
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Test

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DYNAmore Group
�� CAE Software �� Engineering services �� Distributor for LSTC �� Personnel: 70 �� LSTC code developer: 10 �� Head office in
Stuttgart, Germany
5

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DYNAmore Group
�� Sweden
�� 17 Employees �� 37 years in average �� 9 Ph.D. �� 8 M.Sc. �� 1 Economics/Adm
�� Office in Linköping �� Office in Göteborg
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DYNAmore GmbH
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Germany
�� ~60 Employees �� Headquarters in Stuttgart-Vaihingen �� Offices
�� Ingolstadt �� Dresden �� Wolfsburg �� F��rstenwalde (Berlin)
�� On-site Offices
�� Sindelfingen �� Untert��rkheim �� Weissach �� Ingolstadt
Stuttgart [Headquarters]

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Business model
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Technical Software
• Sales
• Support • Training • LS-DYNA • LS-OPT • Ansa • Crash dummies • Crash barriers • Oasys Primer • DynaForm • FormingSuite • Femzip
Software development
• Development • Research • Implementation • Improvement • Support • Material modeling • Contacts • Element technology • Training • GUI development • HPC Cluster
Consultancy work
• Non-linear analysis • Linear analysis • Dynamic analysis • Static analysis • Optimization • Vehicle safety • Explosion analysis • Metal forming • Offshore • Energy • Roadside safety • Accident reconstruction • Vibration and NVH • Thermo-mechanical • On-site
DYNAmore Nordic AB

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DYNAmore Nordic - Selected customers
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DYNAmore Group – Selected customers
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Contact
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�� Software Products
�� Dr. Marcus Redhe �� E-mail: marcus.redhe@dynamore.se �� Mobile: +46 – (0)70 55 131 42
�� Engineering Service and Support
�� Dr. Daniel Hilding �� E-mail: daniel.hilding@dynamore.se �� Mobile: +46 – (0)70 65 366 85
�� Address:
DYNAmore Nordic Brigadgatan 14 587 58 Linköping Sweden
�� Web: http://www.dynamore.se �� Phone: +46 – (0)13 23 66 80

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Introduction to LS-DYNA
2013-09-09 Test
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One code strategy
��Combine the multi-physics capabilities into one scalable code for solving highly nonlinear transient problems to enable the solution of coupled multi- physics and multi-stage problems��
LS-DYNA
Explicit/Implicit Heat Transfer Mesh Free
EFG,SPH,Airbag Particle
User Interface
Elements, Materials, Loads
Acoustics Frequency Response, Modal Methods Discrete Element Method Incompressible Fluids CESE Compressible Fluid Solver Electromagnetism
R7 R7 R7

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SBD – Simulation Based Design
�� Instead of a physical prototype, a virtual
model is created. The purpose of the model is to resemble the behaviour of the physical product.
�� All development/testing is made in the
virtual product. Thus, you treat the model as you would if it was a physical product.
�� The benefits are several:
�� Shorter time to market �� Reduce number of costly prototypes �� Increased innovation �� Lower development costs �� Higher quality
�� �� but also the challenges
�� Rethink development process �� Trust the results �� Educate personnel, new partners..

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Volvo XC60
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What do you need?
PRE-PROCESSOR Generates the FE-model Applies boundary conditions etc SOLVER Solves the numerical model POST-PROCESSOR View the results History? Geometry Material Process
LS-DYNA
Dependence on analysis
LS-PrePost
17
LS-PrePost

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Modify -Process - Initial powder volume -Geometry
Simulation process
2013-09-09 Test
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Build FE-model -Parts -Material -Element
LS-DYNA LS-PrePost/ANSA
Pre – simulation? -Initial stress/stress? - Bolts etc.
LS-PrePost LS-DYNA
Evaluate results
LS-PrePost LS-PrePost

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Introduction to LS-DYNA
2013-09-09 Test
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Keywords and Elements

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Keywords - Define Geometry
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Input file (.k)
length meter millimeter millimeter time second second millisecond mass kilogram tonne kilogram force Newton Newton kiloNewton Young��s modulus of steel 210.0E+09 210.0E+03 210.0 density of steel 7.85E+03 7.85E-09 7.85E-06 gravitation 9.81 9.81E+03 9.81E-03
Newton��s second law, F=ma, requires consistent units
S1 S2 S3

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Keyword User��s manual
2013-09-09 Keyword and Elements
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Input file - Keywords
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*KEYWORD *TITLE Test example $ Control cards govern entire model / simulation *CONTROL_TERMINATION *CONTROL_TIMESTEP $ Define output of results *DATABASE_BINARY_D3PLOT *DATABASE_GLSTAT $ Define section and material *PART $ Define element types and integration *SECTION_SHELL $ Define material properties *MAT_ELASTIC *MAT_FIBER $ Define nodes and elements *NODE *ELEMENT_SHELL $ Define loads and BC *LOAD_NODE *END
Mandatory Mandatory
Input file (.k) Comment card begins with $
PART Material Section Element

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Keyword Format
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Input file (.k) �� Similar functions are grouped together under
the same keyword
�� A data block begins with a keyword and ends
with the next keyword
�� Keywords are left justified �� No distinction between lower and upper case
letters
�� Variables are right justified in their fields �� A ��0�� or blank means that the variable will get
the default value
�� The decimal point is always written out for
floating point variables

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Keyword Format
2013-09-09 Keyword and Elements
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Input file (.k) �� Comments rows are written after a dollar sign in
the first position
�� *COMMENT keyword exist �� Do not use ��tabs�� when editing or creating your
file
�� Line feed signs may cause problems when
transferring files from Dos to Unix

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Keywords - Define Geometry
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Input file (.k)
PART Material Section Element
*NODE $ NID * x * y * z * 1 0.00 0.00 0.00 2 1.0E-2 0 0 3 0.02 0 0 4 2.0E-2 1.0E-2 0 5, 0.01, 0.01, 0.0 6, 0.02, 0.01, 0 $ $ *ELEMENT_SHELL $ID, PID, n1, n2, n3, n4 1, 1, 1, 2, 5, 4 2, 1, 2, 3, 6, 5 0 0.01 0.02 0.01 0 e1 e2 0.02
x y
n1 n2 n3 n4 n5 n6
Free format Fixed format e1 1 2 5 4
ye1 xe1
X
e1
: from n1 to n2
Local coordinate system:
y
e1
: perpendicular to x
e1
directed towards n3
2013-09-09 Keyword and Elements

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Elements
�� Some element formulations are more
costly than others
�� Stresses and strains are calculated at the
integration points
�� Accelerations, velocities and
displacements are evaluated at the nodes
2013-09-09 Keyword and Elements
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Under Integrated and Fully Integrated Elements
�� Most element formulations in LS-DYNA are under-
integrated, i.e. the stresses and strains are only calculated in the mid-point of each element.
�� Advantage: Computational efficiency. The material model
is called once per integration point and time step.
�� Disadvantage: The element formulation contains zero-
energy modes (hourglass modes)
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Integration point (s)

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Under Integrated and Fully Integrated Elements
�� The following element deformation does not yield any
strains in the integration point, and thus no stress
�� There is deformation, but no associated internal energy,
hence the name zero-energy modes.
�� These modes have to be suppressed using ��hourglass
control��
2013-09-09 Keyword and Elements
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��No strain��
x
�� ��
x
�� ��

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Hourglass Control
�� Zero energy modes = Hourglass modes �� Hourglass controlled by *CONTROL_HOURGLASS and
*HOURGLASS
�� Hourglass modes for 1 point integration Q4 shell
elements:
�� Hourglass modes for 1 point integration solid elements:
2013-09-09 Keyword and Elements
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+ 8 more!

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SECTION_SHELL
�� Element formulation
�� Belytschko-Tsay �� Belytschko-Wong-Chiang �� Hughes-Liu �� Belytschko-Leviathan �� Fully integrated shells �� Higher order shells 6/8 noded tria/quad �� ����
�� Element thickness �� Number of integration points through shell thickness
2013-09-09 Keyword and Elements
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Elements (shell) - NIP
�� 1 point integration through the thickness gives a
membrane element
�� 2 point integration through the thickness is the default
(sufficient for a linearly elastic material)
�� For plastic bending behaviour, at least 3 points are
needed through the thickness
�� 5 points recommended for sheet metal stamping.
7 points for springback
�� Use odd numbers to include the neutral axis
2013-09-09 Keyword and Elements
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Element Performance
2013-09-09 Keyword and Elements
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B elytsch k o-T say B elytsch k o-T say + w arp in g stiffn ess B elytsch k o- L eviath an
1 1.07 1.25 1.28 1.49 2.45 2.8 8.8 20 0 5 10 15 20 25
B elytsch k o-W on g- Chian g Hu gh es-L iu F u lly in tegrated B T (typ e 16) Hu gh es-L iu (corotation al) F u lly in tegrated HL F u lly in tegrated HL (corotation al)

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*CONTROL_ACCURACY
�� Invariant node numbering
�� particularly important when large shear forces are present in an
element
�� 2nd order stress update
�� spinning bodies such as turbine blades, rotating tires �� sometimes for stiffness hourglass control �� implicit solutions with large strains in each step
2013-09-09 Keyword and Elements
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Material Models

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Material Models
�� Over 200 models for various applications exists in
LS-DYNA.
�� Determine the stress based on strain, strain-rate,
temp etc.
�� Not materials, but models subject to restrictions:
�� Load magnitude �� Deformation speed (strain rate) �� Temperature
�� The models are defined by material parameters
�� E, ��, ��, etc.
2013-09-09 Material Models
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Hypoelasticity
Hypoelasticity relates a strain rate to a corresponding stress rate Stress is incrementally updated from the strain rate with aid of the constitutive tensor C Most of the materials in LS-DYNA are based on this formulation for the elastic response.
2013-09-09 Material Models
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D:C �� = 
tD t
∆ = ∆ ∆ = ∆
�� �� �� 
E
�� ��
=
Hooke��s law:

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Merits and drawbacks (theoretical)
+
�� It is fairly straightforward to use and easy to implement
in a finite element code
-
�� The response is path-dependent, the stress for a closed
strain cycle can be nonzero, it should be used when the elastic deformation is relatively small
�� It is difficult to deal with anisotropic constitutive models
because the constitutive tensor C is restricted to be isotropic for nonlinear analysis. This is however solved in LS-DYNA with a co-rotational update.
2013-09-09 Material Models
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Hyperelasticity - definition
�� A material is hyperelastic if the internal work is
independent of the deformation path.
�� It is characterized by the existence of a strain energy
function that is a potential for the stress.
�� Typically used when elastic deformation is substantial,
e.g. rubber.
2013-09-09 Material Models
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E E C C S
∂ ∂ = ∂ ∂ =
)( )( 2 W
��
or Green tens - Cauchy Right sor strain ten Green tensor stress Kirchhoff Piola Second C E S

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Stress and strain – uni-axial deformation
2013-09-09 Material Models
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Tensile test: Engineering stress Engineering strain In LS-DYNA: True stress True strain Elastic response: Hooks law: Area reduction:
0 E
A/F
= ��
0 0 E
L/)LL(
- = ��
A/F
= ��
)L/Lln(
0
= ��
L
0
L F F
0
A A )21(AA
0
�ͦ� - =
E�� �� = �� �� E

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Elasto-plasticity in 3-D – multi-axial deformation
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Stress decomposition������.: Von Mises yield criterion��.: Plastic strain��������������:
)(
2 3 p y ijij
ss f
�� ��
- =
    3/ S
kk ij ij ij
�� �� + = ��
Volumetric stress Deviatoric stress
ij p ij
S f
∂ ∂ = ��
��
1
��
3
��
2
��
1
��
3
��
2
��
1
��
3
��
2
��
Perfect plasticity Isotropic hardening Kinematic hardening
p ij
��
p ij
��
p ij
��

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Elastic-visco-plastic material
2013-09-09 Material Models
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*MAT_PIECEWISE_LINEAR_PLASTIC
MID RO E PR SIGY ETAN FAIL TDEL C P LCSS LCSR VP EPS1 EPS2 . . . . . . . . . . EP1 ES2 . . . . . . . . . .
For: Metals, loading exceeding yielding stress, rate effects In: All element types Theory: Isotropic plasticity model with visco-plasticity option E Young's Modulus C,P Strain-rate parameters RO Density LCSS Load curve for PR Poisson's Ratio LCSR Load curve for strain-rate scaling SIGY Yield stress VP Visco-plastic flag ETAN Tangent modulus EPS1�� Piecewise linear def.

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Elastic-visco-plastic material
2013-09-09 Material Models
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Activating visco-plasticity: ( =static yield stress ) No visco-plastic effects Scale by: Scale by: Yield stress is given by: VP=1 is recommended as it uses a consistent visco-plastic theory
⇒ =
0P,C
⇒ = ��
1 VP,0P,C
⇒ - = ��
1 VP,0P,C
⇒ = ��
0 VP,0P,C
ijij P
C
�� �� �� ��
   
= �� ⎠ ⎞ �� ⎝ ⎛ +
, 1
1
kkij ij ij P 1
e, C e 1
�� �� - �� = �� ⎠ ⎞ �� ⎝ ⎛ +

�� ⎭ �� ⎬ ⎫ �� ⎩ �� ⎨ ⎧ �� �� ⎠ ⎞ �� �� ⎝ ⎛ + =
P p eff s y y
C
1
1
�� �� ��

s y
��
s y
��
s y
��

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Elastic-plastic material with Bauschinger efftect
2013-09-09 Material Models
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*MAT_PLASTIC_KINEMATIC
MID RO E PR SIGY ETAN BETA SRC SRP FS VP
For: Metals under large loading In: All element types Theory: Isotropic and kinematic hardening plasticity, viscoplastic E Young's Modulus RO Density PR Poisson's Ratio SIGY Yield stress ETAN Tangent modulus BETA Hardening parameter FS Failure strain SRC Strain rate parameter C VP Rate formulation flag SRP Strain rate parameter P

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Elastic-plastic material with Bauschinger efftect
2013-09-09 Material Models
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Definition of material hardening: Other models with kinematic hardening:
*MAT_PLASTIC_GREEN-NAGHDI_RATE *MAT_ANISOTROPIC_VISCOPLASTIC
Kinematic hardening Isotropic hardening
�� ��
E
0y
��
ETAN
0y
2��
1y
2��
1y
2��
1
= ��
0
= ��

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*EOS
�� Certain material models only solve for the deviatoric part
of the stress tensor
�� An Equation of State (EOS) is required to find the
pressure part of the stress tensor
�� Mostly used in conjunction with fluid-like behaviour (high
explosives, airbag inflation ��)
�� Solid elements only
2013-09-09 Material Models
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Boundary/Initial Conditions

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Initial and Boundary Conditions
�� Variation in time using load curves �� Variation in space �� Arbitrary directions using
�� Local coordinate systems �� Vectors
But limited to cartesian coordinates
2013-09-09 Initial/Boundary Conditions
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)t(u )t( Traction )t(b

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*LOAD
2013-09-09 Initial/Boundary Conditions
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*LOAD_NODE[_SET|_POINT]
NODE/NSID DOF LCID SF CID M1 M2 M3
Nodal loads for one node or a set of nodes DOF Direction of load in current coordinate system LCID Load curve ID for variation in time SF Scale load curve amplitude CID Define a local coordinate system M1-M3 Follower force definition Singularities at point loads may be a problem. Multiple load cards are accumulated.
F F 1M 3M 2M

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*INITIAL
2013-09-09 Initial/Boundary Conditions
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*INITIAL_STRESS[_BEAM|_SHELL|_SOLID] *INITIAL_STRAIN[_SHELL|_SOLID]
Initialise the state of stress and strain in elements Normally used to carry results obtained in one simulation to another. - Multistage forming - Forming -> Crash Keyword data normally generated automatically by preprocessors.

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Kinematic Conditions
�� Prescribe motion in the model �� *BOUNDARY: w.r.t cartesian coordinates
�� Fixed supports �� Symmetric boundaries
�� *CONSTRAINED: internal definitions
�� Mechanical Joints �� Merging shell-brick elements �� Define rigid bodies
2013-09-09 Initial/Boundary Conditions
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*BOUNDARY_PRESCRIBED_MOTION_**
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*BOUNDARY_PRESCRIBED_MOTION[_NODE|_SET|_RIGID]
ID DOF VAD LCID SF VID DEATH BIRTH
Apply nodal displacement, velocity, or acceleration to the model; translations or rotations DOF Direction of load, global or local direction, see manual! VAD Type of load LCID Load curve ID for variation in time SF Scale amplitude of the loadcurve VID Vector ID for vector to be used if DOF=4 or 8 DEATH/BIRTH Active range of time for this boundary condition Use the _RIGID option for rigid bodies. For local directions with rigid bodies see the MAT_RIGID keyword.

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*CONSTRAINED
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*CONSTRAINED_NODAL_RIGID_BODY
PID CID NSID PNODE IPRT
Create a new rigid body using existing nodes PID Part id req. is a unique one CID Coordinate system for output NSID Node set PNODE Optional centre node IPRT Print flag For spot-welds and other types of rigid connections.
RB

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*CONSTRAINED
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*CONSTRAINED_JOINT_��JOINTTYPE��
N1 N2 N3 N4 N5 N6 RPS DAMP
Define mechanical joints between rigid bodies N1-N6 Nodes in the rigid bodies RPS Scale the penalty stiffness DAMP Dynamic damping N1,N3,N6 in RB1. N2,N4,N6 in RB2. Place the nodes in one RB far apart. (N1,N2) etc. initially coincident, except universal joint, read the manual! Motor and gear joints are available for advanced mechanisms.

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*CONSTRAINED
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Cylindrical Revolute Planar Spherical Translational Universal Locking

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Contacts

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Some of the available contacts *CONTACT_option_option_��
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AIRBAG_SINGLE_SURFACE AUTOMATIC_GENERAL AUTOMATIC_GENERAL_INTERIOR AUTOMATIC_NODES_TO_SURFACE AUTOMATIC_NODES_TO_SURFACE_TIEBREAK AUTOMATIC_ONE_WAY_SURFACE_TO_SURFACE AUTOMATIC_SINGLE_SURFACE AUTOMATIC_SURFACE_TO_SURFACE AUTOMATIC_SURFACE_TO_SURFACE_TIEBREAK CONSTRAINT_NODES_TO_SURFACE CONSTRAINT_SURFACE_TO_SURFACE DRAWBEAD ERODING_NODES_TO_SURFACE ERODING_SURFACE_TO_SURFACE FORCE_TRANSDUCER_CONSTRAINT FORCE_TRANSDUCER_PENALTY FORMING_NODES_TO_SURFACE_TIEBREAK FORMING _ONE_WAY_SURFACE_TO_SURFACE FORMING _SURFACE_TO_SURFACE NODES_TO_SURFACE NODES_TO_SURFACE_INTERFERENCE ONE_WAY_SURFACE_TO_SURFACE RIGID_NODES_TO_RIGID_BODY RIGID_BODY_ ONE_WAY_TO_RIGID_BODY RIGID_BODY_TWO_WAY_TO_RIGID_BODY SINGLE_EDGE SINGLE_SURFACE SLIDING_ONLY SLIDING_ONLY_PENALTY SURFACE_TO_SURFACE SURFACE _TO_SURFACE_INTERFERENCE TIEBREAK_NODES_TO_SURFACE TIEBREAK_ SURFACE _TO_SURFACE TIED_NODES_TO_SURFACE TIED_NODES_TO_SURFACE_OFFSET TIED_SHELL_EDGE_TO_SURFACE SPOTWEALD SPOTWEALD_WITH_TORSION TIED_ SURFACE _TO_SURFACE TIED_ SURFACE _TO_SURFACE_OFFSET

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Contact
�� A way of treating interaction between different parts �� Contacts are defined by sets (node/part/segments) or a
box
�� Generally there is a master side and a slave side of the
contact
�� The master side can be a mathematically described with
a geometrical surface (rigid)
�� The thickness of shells are normally taken into account �� Most recommended contacts are based on the penalty
method
�� Several contacts treating special applications exists �� Old contact types kept for
compatibility reasons
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Motion MASTER SLAVE

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Interesting Keywords for Contacts
�� Contacts in LS-DYNA is affected by many different
keywords
�� *SECTION_SHELL (Shell thicknesses,
middle/top/bottom surface meshed)
�� *MAT_xxx (Penalty stiffness, E, pr, dens) �� *DEFINE_FRICTION (Friction behavior between parts) �� *PART_CONTACT (Contact behavior for parts) �� *CONTROL_CONTACT (Overall contact behavior) �� *CONTACT_xxx (Contact definition)
�� The different parameters on different keywords
might be used, depending on contact type.
�� The parameter might have a different meaning
depending on contact type use.
�� Makes contact definition tricky in LS-DYNA!
Some of the most interesting parameters found on different cards will be examined in this presentation.
2013-09-09 Contacts
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master
slave

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Important contact parameters: penalty method (default)
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Contact force
F
i
= ��
i
k
k= interface spring stiffness Solid elements Shell elements K= bulk modulus c = penalty factor
��i= penetration Motion
A V cKA k =
diagonal cKA k =
The time step of the analysis is determined by LS-DYNA from the elements of the FE-mesh without considering the contact interfaces!

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Contact Thickness and Initial Penetrations
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d2 d1
Initial penetration
d2�� d1��
Change of shell thickness only for contact treatment

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Important contact parameters: friction
�� Sliding friction – FS, FD, DC and VC
�� Defined in keyword *CONTACT �� Based on Coulomb friction �� Default values gives no friction �� FS and FD are static respectively dynamic friction coefficient �� DC - decay coefficient �� If FD and FS not are equal, then FD should be less than FS
and DC nonzero
�� VC is the coefficient for viscous friction and limits the friction
force (typically 3-½ of yield stress)
�� Viscous damping VDC improves stability. For metal contacts use
20% and for soft material 40-60%
2013-09-09 Contacts
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rel
VDC c
eFD FS FD
-
- + =
) (
��

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Automatic contacts without self contact
�� *CONTACT_AUTOMATIC_NODES_TO_SURFACE �� *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE
�� Thickness taken into account �� Contact surface is offset by half thickness from mid-plane �� Orientation of segments not needed �� Contact from both sides �� Handles disjoint meshes �� Applies a smooth surface based on a
radii at the edges (including free edges)
�� Initial penetrations are detected �� Possible to change or scale contact thickness �� Friction and damping available
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Single-surface contacts (self contact)
�� *CONTACT_AUTOMATIC_SINGLE_SURFACE �� *CONTACT_AUTOMATIC_GENERAL
�� Same features as the
automatic contacts
�� Only require definition of
the slave surface
�� Include self contact �� Sensitive to initial penetrations �� Possible to use only one contact
definition forthe complete model
�� Beam and edge to edge contacts
are included *CONTACT_AUTOMATIC_GENERAL
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Edge/Beam Contacts
�� *CONTACT_AUTOMATIC_GENERAL (26)
�� exclude interior edges �� entire length of each exterior edge is checked for contact �� OBS, the edge cylinder is not affected by OPTT or TH when
using part_contact.
�� *CONTACT_AUTOMATIC_GENERAL_INTERIOR (i26)
�� like *CONTACT_AUTOMATIC_GENERAL, �� but interior edges are treated like exterior edges �� Alternative way to treat edge contact: �� creating null beam elements (*ELEMENT_BEAM,*MAT_NULL)
approximately 1mm in diameter along every edge wished to be considered for edge-to-edge contact and including these null beams in a separate AUTOMATIC_GENERAL contact
�� *CONTACT_SINGLE_EDGE (22)
�� Treats only edge-to-edge contact �� no thickness offset at the contact edge
�� *CONTACT_xxx_MORTAR ()
�� edge-to-edge contact �� no thickness offset at the contact edge
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65
d d/2

Page 63
Tied contacts
�� CONTACT_TIED_NODES_TO_SURFACE �� *CONTACT_TIED_SURFACE_TO_SURFACE �� *CONTACT_TIED_SHELL_EDGE_TO_SURFACE
��._OFFSET
�� Possibility to ��tie�� nodes to a surface (segment) �� NODES_... and SURFACE_... ties translational d.o.f �� SHELL_EDGE_.. ties translational and rotational d.o.f �� Constraint based. Thus, will not work with rigid bodies. �� ��_OFFSET allows for a segment thickness and is penalty based. �� ��_TIEBREAK_... has failure options. �� Can be used to model glue, spotwelds etc.
2013-09-09 Contacts
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Page 64
Control Cards & Execution

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Control Cards
�� The purpose is:
�� Activate solution options;
implicit solution, adaptive remeshing, mass scaling ��
�� Change default values on options and parameters
�� Remember that:
�� Ordering between them and position are arbitrary
Good practise is to put them first in your input file
�� Do not use more then one control card of each type �� All control cards are optional except
*CONTROL_TERMINATION
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Control Card Default Values
�� Default values exist for all options and most parameters �� Control cards change default values globally �� Default values are defined hierarchically
The order between them are:
�� LS-DYNA defaults �� Control card input �� Individual Keyword input
�� Set your defaults with the control cards and change the
keyword input where default values not should be used
�� Input of ��0�� will normally give the default value which is
shown in the manual
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Page 67
Most Important Control Cards
�� Always consider the following control cards since
they can strongly affect your results or output
�� *CONTROL_ACCURACY �� *CONTROL_CONTACT �� *CONTROL_ENERGY �� *CONTROL_HOURGLASS �� *CONTROL_SHELL �� *CONTROL_SOLID �� *CONTROL_TERMINATION �� *CONTROL_TIMESTEP
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Implicit Solution Types
�� Linear Analysis
�� static or dynamic �� single, multi-step
�� Eigenvalue Analysis
�� frequencies and mode shapes �� linear buckling loads and modes �� modal analysis: extraction and superposition �� Dynamic analysis by modal superposition (971)
�� Nonlinear Analysis
�� Newton, Quasi-Newton, Arclength solution �� static or dynamic
�� default LS-DYNA: static and nonlinear!
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Output Files
�� Binary files (can be viewed in LS-PrePost)
*DATABASE_BINARY_Option
�� ASCII files for more detailed output
(graphs can be shown in LS-PrePost) *DATABASE_Option
�� Data in the binary and ASCII files is controlled by
*DATABASE_EXTENT_Option *DATABASE_HISTORY_Option
�� Control files (d3hsp) �� Message files (messag)
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Output Files
�� D3PLOT (database for complete output states) �� D3DUMP (complete database for restart) �� RUNRSF (running restart file, overwritten) �� D3PART (as D3PLOT but includes just specified parts) �� D3THDT (database for time history data of element
subsets)
�� D3DRLF (dynamic relaxation database) �� D3MEAN (CFD database) �� INTFOR (database for output of contact interface data) �� XTFILE (extra time history data) �� D3EIGV (modal data from eigenvalue analysis) �� D3CRCK (crack data from Winfrith concrete model)
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ASCII Output Files
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�� GLSTAT (global data) �� MATSUM (material energies) �� RCFORC (resultant interface
forces)
�� SLEOUT (sliding interface energy) �� NODOUT (nodal point data) �� ELOUT (element data) �� SECFORC (cross section forces) �� RWFORC (rigid wall forces) �� SSSTAT (subsystem data) �� DEFORC (discrete elements) �� NCFORC (nodal interface forces) �� DEFGEO (deformed geometry) �� SPCFORC (SPC reaction forces) �� NODFOR (nodal force groups) �� ABSTAT (airbag statistics) �� BNDOUT (boundary condition
force/ energy)
�� RBDOUT (rigid body data) �� GCEOUT (geometric contact
entities)
�� JNTFORC (joint force) �� SBTOUT (seat belt output) �� AVSFLT (AVS database) �� SWFORC (nodal constraint
reaction forces)
�� MOVIE �� MPGS �� TRHIST (trace particle
history)
�� TPRINT (thermal output) �� SPHOUT (SPH data)

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Demonstrate LS-PrePost
�� PreProcessing �� PostProcessing
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Thank you!
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77
Test
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