femfat 5.4 news and more
TRANSCRIPT
FEMFAT 5.4News and MoreGaier
Steyr
2019
• VISUALIZER: Animation of equivalent stress and damage, video export
• VISUALIZER: Additional WELD definition settings
• New SPOT method: Assessment of stresses of NASTRAN super-elements
• SPOT additional report file output of fatigue dataset name
• New WELD stress interpolation method: Hot spot stress concept
• STRAIN input file analogous MAX
• SPECTRAL: Improved mean stress influence
• Filter function for group list
• FEMFAT parallelization: Delete automatically temporary files after analysis
• FEMFAT inside ANSYS
• Template for elastomers analysis settings
FEMFAT 5.3.1 available since August 2018
Date: 2019 / Author: Gaier 2© MPT Engineering / Disclosure or duplication without consent is prohibited
Animation of FEMFAT Results
3© MPT Engineering / Disclosure or duplication without consent is prohibited
• Define in FEMFAT a
„DETAILED RESULTS“
nodal group for animation
• Select the new result
category „Animated
Results“ in the Result
Selector dropdown menu
• Color for nodes without
value can be defined also
for animated results
Date: 2019 / Author: Gaier
Animated Results GUI
4© MPT Engineering / Disclosure or duplication without consent is prohibited
• Selectable result types
• Currently selected time step as shown on the geometry
• Options for animating the results
• For Example: run an animation „From“ time step 1 „To“
time step 681 and show every 10th time step
(„Increment“).
• The „Delay“ of 100 [ms] refers to the time interval
between two rendering processes. The Delay does not
include the rendering time.
• Options to circle the animation („Loop“) and save
Screenshots of the shown time steps („Export…“)
• Animation Controls
Date: 2019 / Author: Gaier
Video Export
Date: 2019 / Author: Gaier 5© MPT Engineering / Disclosure or duplication without consent is prohibited
High
Medium
Low
Equivalent stress
Partial damage
Total damage
Additional Settings for Welding Seam End Definitions
Date: 2019 / Author: Gaier 6© MPT Engineering / Disclosure or duplication without consent is prohibited
• Spots are mostly represented with simple models
• Usage of detailed spot models without the disadvantages of
“too many DOFs”
• Aim is one FEA for all spots in trimmed BIW(No post-processing of FEA is necessary)
Usage of NASTRAN super-elements
New SPOT Method by Using Nastran Super-ElementsMotivation
Date: 2019 / Author: Gaier 7© MPT Engineering / Disclosure or duplication without consent is prohibited
Workflow: Usage of Super-Elements
Date: 2019 / Author: Gaier 8© MPT Engineering / Disclosure or duplication without consent is prohibited
Replace hexas by
super-elements
connected by 4
nodes/sheet via RBE3
Pre-Proc
BIW sheet structure with
hexa elements connected
by RBE3 to sheets
NASTRAN
Op2-file
Post-Proc
Op2-file
Post-
processing
Database with
super-elements
and stiffness
matrices
External super-elements
(Super-elements are imported)
→ supported by FEMFAT
Model with Super-Elements using ANSA
Date: 2019 / Author: Gaier 9© MPT Engineering / Disclosure or duplication without consent is prohibited
Super-element 4
Super-element 1 Super-element 3
Super-element 2
ANSA creates a hexahedron
element for visualization
ANSA Connection Manager
Results, Global behavior
Date: 2019 / Author: Gaier 10© MPT Engineering / Disclosure or duplication without consent is prohibited
Model without super-elements,
but with detailed SPOT solid
model connected via RBE3-
elements to shell structure
Model with super-elements
• Advantages– Applicable to all types of spot joints (spot welds, rivets, nails, …)
– Detailed FE-model of notch of spot-> accurate stiffness and stress results
– Assessment of stresses with one master S-N curve independent from load type and direction
– Detection of crack location in detailed FE-model
– Correct superposition of stresses (Maximum stresses of different load cases may be at different locations)
– Detailed FE-model needs to be generated and analyzed only one time-> data (model and stiffness) can be stored in a database
• Disadvantages– Linear model
– Special know-how for applying super-element concept is necessary
– Higher computation effort
– No easy distinction between failure modes (sheet or nugget failure)
Usage of Super-Elements
Date: 2019 / Author: Gaier 11© MPT Engineering / Disclosure or duplication without consent is prohibited
SPOT Output of Fatigue Dataset Name
Date: 2019 / Author: Gaier 12© MPT Engineering / Disclosure or duplication without consent is prohibited
VISUALIZER
Joint 1: ConnD (in more than one FEMFAT analysis joint)
Connector Element(s): 1440, 1441, 1446
Stress based Assessment
NodeLab CenterLab Safety Loc. Angle Amplitude MeanStress ElemLab PropID FatigueID
3459 42 3.520e-03 top 90.0 6.589e+04 6.589e+04 2742 1000002 std_spot_stress_fatigue_data_steel
Report File
• Extension of the automatic stress correction
• New formula:
– Standard method:
– New hot spot stress method:
• The hot spot stress concept is applied automatically, if
necessary values are activated in the WELD database
WELD: New Hot Spot Stress Interpolation Method
Date: 2019 / Author: Gaier 13© MPT Engineering / Disclosure or duplication without consent is prohibited
DAssesspoint.= f (0.5 tNeighbor + tmin)
DAssesspoint = a tNeighbor + b tEvalulated
tEvalulated
tNeighbor
STRAIN Comp Input File .sco
Date: 2019 / Author: Gaier 14© MPT Engineering / Disclosure or duplication without consent is prohibited
-1
3001
Management of Strain Gage Data of Comp
Text:
Text:
Text:
Text:
---------------------------------------------------
1 -
Mode (CTR, ALL, N2N) : CTR
Gage Type (LIN, R45, R60) : LIN
Element 1 : 80
File Name :
Grid 1 - File Column : 1
Grid 1 - Initial Elongation : 0.000000
Dimension (----, µm/mm, µm/m) : ----
Multiplication Factor : 1.000000
Repetition Factor : 1
---------------------------------------------------
...
---------------------------------------------------
...
-1
-1
3002
Extended Strain Gage Data of Comp
Text:
Text:
Text:
Text:
Material Behaviour - Cyclic Hardening/Softening (ON, OFF) : OFF
Output - Stress Comparison (ON, OFF) : ON
Output - Strain Comparison (ON, OFF) : ON
Signal Length - Finite Element Data [sec] : 1.000000
Signal Length - Measurement Data [sec] : 1.000000
-1
STRAIN Calc Input File .sca
Date: 2019 / Author: Gaier 15© MPT Engineering / Disclosure or duplication without consent is prohibited
-1
4001
Management of Strain Gage Data of Calc
Text:
Text:
Text:
Text:
---------------------------------------------------
1 -
Gage Type (LIN, R45, R60) : LIN
Notched Structure (YES, NO) : NO
File Name :
Grid 1 - File Column : 1
Grid 1 - Initial Elongation : 0.000000
Dimension (----, µm/mm, µm/m) : ----
Multiplication Factor : 1.000000
Repetition Factor : 1
---------------------------------------------------
2 -
Gage Type (LIN, R45, R60) : R45
Notched Structure (YES, NO) : YES
Select Gradient/Radius (GRAD, RAD): GRAD
Gradient : 0.500000
...
---------------------------------------------------
...
-1
-1
4002
Extended Strain Gage Data of Calc
Text:
Text:
Text:
Text:
Angle between cutting-planes [°] : 10.000000
Number of rainflow-classes : 64
Factor for residue load cycles : 0.500000
-1
SPECTRAL: Improved Mean Stress Influence
Date: 2019 / Author: Gaier 16© MPT Engineering / Disclosure or duplication without consent is prohibited
Mean stress influence is always
analyzed with R=const option to
ensure an intersection point with
the Haigh-diagram
For constant stress without mean
stress influence two options are
availableA
+ M- M
HAIGH
const
Filter Function for Group List
Date: 2019 / Author: Gaier 17© MPT Engineering / Disclosure or duplication without consent is prohibited
Without filter With filter
• For saving disk space, a button can be activated to delete all
files in the parallel-subdirectories automatically after a
successful parallel FEMFAT analysis
• Only message (.msg) and report (.pro) files will not be deleted
Parallel Analysis: Remove Temporary Files
Date: 2019 / Author: Gaier 18© MPT Engineering / Disclosure or duplication without consent is prohibited
FEMFAT inside ANSYS: One continuous workflow
The use of design points and optimization tools is fully supported.
19
All files which are relevant for the simulation are automatically stored and updated
in one folder.Date: 2019 / Author: Gaier © MPT Engineering / Disclosure or duplication without consent is prohibited
Complete Job Definition and Full Result Visualization in ANSYS Mechanical
20Date: 2019 / Author: Gaier © MPT Engineering / Disclosure or duplication without consent is prohibited
• Automatic adjustment of the necessary FEMFAT settings for elastomer components which undergo large deformations– Consistent stress transformation
– Deactivated stress gradient
– Deactivated PLAST
– User defined mean stress
– Normal stress in critical plane
– Miner elementary with R = const.
– 3D-stresses, all nodes
Template for Elastomers Analysis Settings
Date: 2019 / Author: Gaier 21© MPT Engineering / Disclosure or duplication without consent is prohibited
Increasing fatigue
limit because
polymer chains
orient themselves
towards load
direction and block
cracks.
• New ChannelMAX scratch format based on HDF5:– Flexible database format with direct data access, e.g. for
future developments of sophisticated stress gradient methods
– Less space on hard disk and faster
– Standard format for FEMFAT analysis and VISUALIZER
– General data format applicable also for BASIC, TransMAX, SPECTRAL
– Suitable for future parallelization of scratch and analysis process
• VISUALIZER: Maximum/Minimum Search
• Boundary Layer:– Improved stress gradient analysis
– Display of FEA-stresses at surface and transition in VISUALIZER
• Script for automatic detection of weld lines
• Support Abaqus odb 2018 & 2019
FEMFAT 5.3.2 released in February 2019
Date: 2019 / Author: Gaier 22© MPT Engineering / Disclosure or duplication without consent is prohibited
Stress Gradient Calculation Problem and Solution
© MPT Engineering / Disclosure or duplication without consent is prohibited
Stress gradient perpendicular to the front
surface is almost zero
Results are too conservative
Solution: Results are Calculate Gradient
in three orthogonal directions
Resulting stress gradient is the length
of the stress gradient vector:
0,01*d
1
2
3
2
3
2
2
2
1'
Date: 2019 / Author: Gaier 23
• weldseamscanner.exe
Weld Seam Scanner
Date: 2019 / Author: Gaier 24© MPT Engineering / Disclosure or duplication without consent is prohibited
• VISUALIZER: New reliable definition algorithm for double-row welds (overlapped weld, edge joint, laser weld, flared joint, etc.)
• VISUALIZER and WELD: Support of degenerated double-rowed welds
• VISUALIZER: Delete multiple welds with rubberband selection
• VISUALIZER: Simultaneous display of SPOT detailed and base material results
• SPECTRAL analysis of SPOT joints
• SPECTRAL Neuber Correction with PLAST
FEMFAT 5.4 (planned for June 2019)
Date: 2019 / Author: Gaier 25© MPT Engineering / Disclosure or duplication without consent is prohibited
• Output stress and damage histories as RPC binary files (e.g. for FEMFAT LAB)
• Safety factor analysis: Output of fatigue strength at given cycles(GUI & report file)
• Compressed ANSYS RST Interface
• Performance enhancements forparallel processing
• SPECTRAL interface for PERMAS (based on Medina.bof)
• Job-file: Select material by name
• SPOT parallel analysis: Merge report file
FEMFAT 5.4 (planned for June 2019)
Date: 2019 / Author: Gaier 26© MPT Engineering / Disclosure or duplication without consent is prohibited
setValue {} {} FatParamMaterial {test}
→ test.esh.tim
→ test.pdh.tim
→ test.tdh.tim
VISUALIZER: New reliable definition algorithm for double-rowed welds
Date: 2019 / Author: Gaier 27© MPT Engineering / Disclosure or duplication without consent is prohibitedEdge Joint
Overlap Joint Laser Joint
Overlap Joint Flared Joint
Complex meshing of connecting sheet (multi-row and triangle elements)
VISUALIZER: Support of degenerated double-rowed welds
Date: 2019 / Author: Gaier 28© MPT Engineering / Disclosure or duplication without consent is prohibited
Overlap Joint Edge Joint
VISUALIZER: Delete multiple welds
Date: 2019 / Author: Gaier 29© MPT Engineering / Disclosure or duplication without consent is prohibited
SPECTRAL Analysis of SPOT Joints
Date: 2019 / Author: Gaier 30© MPT Engineering / Disclosure or duplication without consent is prohibited
SPECTRAL Neuber Correction with PLAST
Date: 2019 / Author: Gaier 31© MPT Engineering / Disclosure or duplication without consent is prohibited
Dirlik without PLAST PLAST Mean PLAST Mean + Amplitude
Date: 2019 / Author: Gaier © MPT Engineering / Disclosure or duplication without consent is prohibited 32
Date: 2019 / Author: Gaier © MPT Engineering / Disclosure or duplication without consent is prohibited 33