bone density modeling
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Transcript bone density modeling
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
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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
8
131K dof / proc
.47 Teraflops - 4088 processors
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