High Performance Engine Analysis using HyperWorks and PERMAS
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Transcript of High Performance Engine Analysis using HyperWorks and PERMAS
High Performance Engine Analysis using HyperWorks and PERMAS
08.11.2011 INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 1
Michael Klein, INTES GmbH
High Performance Engine Analysis
Our guideline:• High performance for industrial usage• High performance for every day usage• No extra effort to use high performance
Required for high performance engine analysis:
AGENDA/CONTENTS
� Company – background in high performance computing
Required for high performance engine analysis:• Preprocessor interface with support of all features • High accuracy: only with more precise modeling
and correct simplifications the benefit from finer meshes is a more accurate result
• High performance features that result in shorter run times for a wide range of analysis
• Efficiency in postprocessing
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 2
� HyperMesh-PERMAS interface
� Bolt pretension Process modeling/loadhistoryContact
� New gasket-element solver
� PERMAS-HyperView interface� Conclusion
08.11.2011
Company
INTES• Privately held and independent Finite Element(FE) Technology company
• Founded in 1984 as spin-off of Stuttgart University• Offering own FE analysis software PERMAS,software development, and engineering services
• Based on long-term experience in thedevelopment of numerical FE methods
PERMAS FEA Software
Thermo-mechanical analysis:• Linear and non-linear static analysis• Contact analysis• Linear and non-linear heat transfer (steady-state and transient)
Vibroacoustic analysis:• Dynamic analysis (in time and frequency domain)• Fluid-structure acoustics• Spectral and random response analysis
Interfaces:• HyperMesh-PERMAS Interface since 2005 (developed by Altair)• PERMAS-HyperView Interface since 2005 (developed by INTES)• PERMAS-MotionSolve Interface (developed by INTES) 3
• High performance− Large models− Fast solvers− Parallelization
• Special algorithms− Contact Analysis− Gasket Analysis− Eigenvalues with MLDR− Fluid-structure coupling
• Productivity tools− Automatic part coupling and
incompatible meshes− Substructuring and submodelling− Direct interfaces
PERMAS FEA SoftwareGeneral purpose software to perform complex FE calculations in engineering
Full Set of Features for Engine Analysis
coupling of incompatible meshes
bolt pretension
nonlinear material behavior
gasket elements
press fit
08.11.2011 INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 4
(transient) heat transfer analysis (result transfer)
contact analysis
nonlinear load history
integration analysis (static with subsequent dynamic analysis)
static analysis
Bolt Pretension
For bolt pretension a simplification in modeling is required, because bolt with all details like the thread raises analysis duration drastically.Simplification should always represent the mechanical behavior simpler, but correct.Example: classical and widely used pretension based on a surface inside the bolt.
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 5
Advantages:� Simple input� Exact definition of pretension force
Disadvantages:� Shortening of bolt in simulation instead of elongation in reality� Wrong direction of radial forces in thread area (radial tear instead of radial spreading)
08.11.2011
Bolt Pretension Applied to Thread
New method with bolt pretension applied to thread area.
Advantages:� Simple input� Exact definition of pretension force� Pretension in thread area
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 6
� Elongation of bolt, like in reality� Same/less effort for definition� Same analysis time� Better mechanics
Disadvantages:� Wrong direction of radial forces in thread area
08.11.2011
Bolt Pretension Applied to Thread
New method with bolt pretension applied to thread area.Simple input of optional alpha !
Additional advantages:� Forces in direction of flank angle� Radial spreading, like in reality
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 7
flank angle alpha
08.11.2011
Bolt Pretension Applied to Thread
New method with bolt pretension applied to thread area.Simple input of optional alpha !Simple input of optional pitch !
Additional advantages:� Forces in direction of flank angle
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 8
flank angle alpha
pitch
� Radial spreading, like in reality� Load path like in reality� Torque in bolt
08.11.2011
Pretension/Contact in HyperMesh
Complete range of all available contact and pretension definitions.
Input of all required and optional parameters like: • Optional alpha and• Optional pitch .
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 9
• Optional pitch .
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Process Modeling/Load History - Basics
• Complex analysis like engine analysis are characterized by an analysis process that consists of several steps.
• Typical steps are:– bolt pretension, – bolt force loss, – overclosure of parts, – friction relaxation,
− heat up,− cool down− firing cylinder and− …– friction relaxation,
• But with an excellent fine meshed model and a misty load sequence the results are misty!
• Precise tool for definition of load sequences is required for high performance analysis, if you want to get high accurate results.
• Simple error protective engineering method with good visual feedback for checking is used with PERMAS/Hypermesh:
– Load definition by function over load steps.
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 10
− …
08.11.2011
Load History - HyperMesh
• Example:Step 1: Bolt pretension force of 100%Step 2: Bolt force loss to 90% after
assemblyAll subsequent steps: Bolt lock
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 11
• HyperMesh:Definition and visual feedback in‘PERMAS LOADING Browser’
Advantages:� Simple input� Clear definition of load at any time
of the load history� Checkable (visual)
08.11.2011
FE-Model
Load History
Drawing
Assembling Operating load
operatingload
collar
washer
pretension
contact collar-washer
contact
shaft1 2 3 4 5
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 12
Frictional ContactDefinition
PretensionDefinition
Fixed
contactcollar-shaft
Easy description of nonlinear load history
Definition of contact-, load- and pretension-behavior
Description of behavior by function over load steps
08.11.2011
Contact Analysis
Contact is a general high performance feature of PE RMAS
• Ongoing development of unique method since 17 years
• Very efficient (for large models)
• Highly accurate (without artifical stiffness)
• Comfortable modeling (compatible and incompatible meshesof contact partners)
• Complete set of results
Sliced model
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 13
• Full parallelization for high performance
• Static and sliding friction
Frictional forces after assembly/pretension (step 1)
Contact status and frictional force vectors after full load (step 5)
08.11.2011
Gasket Elements - Modeling
engine-block
engine-head
gasket layer
Single gasket element details
physical gap → contact gap
physical behavior → material
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 14
One layer of engine gasket with beads
Physical gap is modeled with PERMAS contact gap- Best performance- Like reality, no stiffness
Physical behavior from measurement in main direction as PERMAS material input
- Pressure- Closure- Loading- Unloading- Plastic- Elastic
closure
pres
sure
08.11.2011
Contact Controlled Nonlinear Gasket
NLMATERIAL-iteration
plastic_mat
σ
ε
Workflow of analysisNLMATERIAL-iteration encloses CA-iteration→ during each NLMATERIAL-iteration a complete CA-iteration is done
Solution of:plastic materialnonlin. elasticitygasket material…
with iteration overstiffness matrix
shift gasket solution from NLMATERIAL-iteration to PERMAS’s best in class CA-iteration
saves time by shift from outer loop to inner loop
takes advantage of solution
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 15
CA-iteration
iteration ε
gasket_mat
closure
pres
sure
Solution of:contactnormal forcefriction forcefriction direction
pretension
with iteration overflexibility matrix
takes advantage of solutionin flexibility matrix
reduction of computation time
+ gasket material
08.11.2011
Contact Controlled Nonlinear GasketGasket is the Only Nonlinear Material
NLMATERIAL-iteration
Workflow of analysisNLMATERIAL-iteration not needed → only CA-iteration is done
Several engine analysis are done with linear materi al
Then the only nonlinearities are contact, pretensio n and gasket material (no linearization)
All nonlinearities are now solved by PERMAS contact iteration, with same/better result quality
NLMATERIAL-iteration is not needed
► Drastic reduction of computation time
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 16
CA-iteration
iteration
gasket_mat
closure
pres
sure
Solution of:contactnormal forcefriction forcefriction direction
pretension+ gasket material
with iteration overflexibility matrix
Drastic reduction of computation timeBreakthrough in engine analysis
STATIC
Still full nonlinear loading/unloading
08.11.2011
Benchmark Results Engine Nonlinear Model (plasticity, temperature dependency)
15
20
25
888.687 nodes516.809 elements (tet10, hexe8, x2stiff3)
2.498 gasket elements2.046 multipoint constraints
2.638.812 dofs24.694 ca dofs
11 steps: pretension, thermal load (hot/cold),
factor >2
elapsed run time [hours]
22.5
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 17INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 17
0
5
10
PAXVILLE, 4 x Xeon MP Dual Core with 3,4 GHz, 26.000 MB memory, parallelization
11 steps: pretension, thermal load (hot/cold),firing, interference
11.0
22.5
old51 GB disc space
new GSKSOLV=CONTACT
51 GB disc space
Model of half a six-cylinder engine appears by courtesy of Ford Motor Company in Detroit, Michigan, USA
picture of a prequel engine model
08.11.2011
Benchmark Results Detroit Diesel EngineOnly Nonlinear Contact and Gasket
753.799 nodes942.497 elements (tet4, tet10, hexe8, x1stiff3)
9.765 gasket elements3.329 multipoint constraints
2.209.978 dofs18.189 ca dofs
5 steps : pretension, thermal load,
elapsed run time [hours]
2
2,5
3
3,5
factor 4.7
3.40
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 18
PAXVILLE, 4 x Xeon MP Dual Core with 3,4 GHz, 26.000 MB memory, parallelization
5 steps : pretension, thermal load,firing with different pressure levels
Model of half a six-cylinder Diesel engine appears by courtesy of Daimler Trucks North America in Detroit, Michigan, USA
0
0,5
1
1,5
2
0.72
3.40
old56 GB disc space
new GSKSOLV=CONTACT
29 GB disc space
48% saved
08.11.2011
Benchmark Results Big EngineOnly Nonlinear Contact and Gasket
9.412.073 nodes6.857.322 elements (tet4, tet10, penta6, hexe8)
1.639 gasket elements
elapsed run time [hours]
40
50
60
Formerly huge pure linear models can now be calculated with full nonlinear gasket behavior.
?
?
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 19
BOXBORO, 4 x INTEL Xeon X7560 Octa Core with 2,27 GHz, 110.000 MB memory, parallelization
1.639 gasket elements22.263 multipoint constraints
28.126.871 dofs51.232 ca dofs
6 steps : pretension, thermal load,firing of each cylinder
4 cylinder engine
0
10
20
30
3.2
new GSKSOLV=CONTACT
574 GB disc spaceold
? disc space
?
08.11.2011
Benchmark Results Engine 3Only Nonlinear Contact and Gasket
2.578.885 nodes1.476.012 elements (tet10, penta6, penta15,
hexe8, hexe20, tria3, quad4, x2stiff3)
2.044 gasket elements2.751 multipoint constraints
7.669.010 dofs21.762 ca dofs
elapsed run time [hours]
40
50
60
70
factor 20.8
68.3
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 20
PAXVILLE, 4 x Xeon MP Dual Core with 3,4 GHz, 26.000 MB memory, parallelization
7 steps : pretension, thermal load,firing with different pressure levels
5 cylinder enginewith attached parts
0
10
20
30
3.27
68.3
old137 GB disc space
new GSKSOLV=CONTACT
87 GB disc space
37% saved
08.11.2011
Turbocharger for Engine Analysis -Contact Status Files (CAS/CASO Files)
Contact status files serve for easy job recovery and/or considerable run-time acceleration of successive variants.
Contact status files save time by giving a suitable starting vector for contact iteration
CAS/CASO files can be saved every time, because they need very little disc space.Disc space example for Engine 3:
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 21
vector for contact iteration based on similarity.
With the new contact controlled nonlinear gasket analysis the gasket element solution is now part of CAS/CASO files.
Now engine analysis with gaskets considerably benefits from CAS/CASO files method.
Disc space example for Engine 3:a) save Database for restart: up to 87.000 MBb) save CAS/CASO files: about 2 MB
Typical Scenarios for CAS/CASO files
Simulation of variants
Restarts
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CAS/CASO Files – Reduction of Run Time
elapsed run time [hours]
40
50
60
70
factor 20.8
68.3 1
1,5
2
2,5
3
3,5
elapsed run time [hours]
Additionalfactor 1.8(factor 38overall)
1.8
3.27
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 22
PAXVILLE, 4 x Xeon MP Dual Core with 3,4 GHz, 26.000 MB memory, parallelization
2.578.885 nodes1.476.012 elements (tet10, penta6, penta15,
hexe8, hexe20, tria3, quad4, x2stiff3)
2.044 gasket elements2.751 multipoint constraints
7.669.010 dofs21.762 ca dofs
0
10
20
30
3.27
68.3
old137 GB
1.80
PERMASdisc space
0
0,5
1
7 steps : pretension, thermal load,firing with different pressure levels
new87 G
1.8
new CONTACT+CASO88 GB disc space
new GSKSOLV=CONTACT
87 GB disc space
new+CASO88 GB
GSKSOLV=
08.11.2011
Postprocessing - HyperView
Direct binary interface from PERMAS to HyperView• PERMAS writes H3D• No file conversion required• Fast read in• Smallest possible file size• All PERMAS results available
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 23
E.g. contact results:• All time steps• All results, also model
checking results• Contour plot or• vector plot, …
08.11.2011
Postprocessing - HyperView
E.g. contact results:• All time steps• All results, also model
checking results• Contour plot or• Vector plot, …
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 2408.11.2011
Postprocessing - HyperView
E.g. contact results:• All time steps• All results, also model
checking results• Contour plot or• Vector plot, …
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 2508.11.2011
Postprocessing - HyperView
E.g. contact results:• All time steps• All results, also model
checking results• Contour plot or• Vector plot, …
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 2608.11.2011
Conclusion
• High performance engine analysis is useful:– if you can use it in your every day work and– if you have tools for all steps of the process that support high
performance analysis.
• HyperWorks and PERMAS together support all steps of high performance engine analysis.
INTES GmbH, Schulze-Delitzsch-Str. 16, D-70565 Stuttgart www.intes.de 27
high performance engine analysis.
Your benefit:�More variants in the same time or�Better results by finer models in the same time,� Leads to better understanding of the mechanical
behavior,� Leads to better products.
08.11.2011