Transcript bone density slides

Ultrascalable Implicit Finite
Element Analyses in Solid
Mechanics with over a Half a
Billion Degrees of Freedom
(excerpts)
Mark F. Adams
H.H. Bayraktar, T.M. Keaveny, P. Papadopoulos and Atul Gupta
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Trabecular Bone
Cortical
bone
Trabecular
bone
5-mm Cube
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Methods:
FE
modeling
Mechanical Testing
E, yield, ult, etc.
3D image
FE mesh
3
Micro-Computed Tomography
CT @ 22 m resolution
2.5 mm cube
44 m elements
the vertebral body you are showing is pretty healthy from a 80
year old female and it is a T-10 that is thoracic. So it is pretty
close to the mid-spine. Usually research is done from T-10
downward to the lumbar vertebral bodies. There are 12
4 VB's and 5 lumbar. The numbers go up as you go
thoracic
down.
1 mm slice from vertebral body
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Vertebral Body With Shell
 Large deformation elast.
 6 load steps (3% strain)
 Scaled speedup
 ~131K dof/processor
 7 to 537 million dof
 4 to 292 nodes
 IBM SP Power3
 14 of 16 procs/node
80 µm w/ shell
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Computational
Architecture
 Athena: Parallel FE
 ParMetis
FE Mesh
Input File
Athena
Partition to SMPs
FE input file
FE input file
(in memory)
(in memory)
Athena
 Parallel Mesh Partitioner
(Univerisity of Minnesota)
ParMetis
Athena
File
File
File
File
FEAP
FEAP
FEAP
FEAP
 Prometheus
 Multigrid Solver
 FEAP
 Serial general purpose
FE application (University
of California)
 PETSc
 Parallel numerical
libraries (Argonne National
Material Card
pFEAP
Silo DB
Silo DB
Silo DB
Silo DB
Olympus
Prometheus
Visit
Labs)
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ParMetis
ParMetis
PETSc
METIS
METIS
METIS
METIS
ParMetis partitions
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131K dof / proc
.47 Teraflops - 4088 processors
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