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On Computational Structures Technologies. 기계항공 공학부 , 서울 대학교 김 승 조 2006, 11, 21 Supercomputing Korea 2006. ASTL. A ero ST ructures L ab. Contents. Introduction History of Finite Element Analysis Representative Structural Analysis Codes Large Scale Parallel Structural Analysis Code - PowerPoint PPT Presentation
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IPSAP/EXPLICIT
VIBRATION ANALYSIS
STRESS ANALYSIS
기계항공 공학부 , 서울 대학교김 승 조
2006, 11, 21
Supercomputing Korea 2006
On Computational Structures Technologies
Aero STructures Lab.
http://aeroguy.snu.ac.kr2/52
Introduction
History of Finite Element Analysis
Representative Structural Analysis Codes
– Large Scale Parallel Structural Analysis Code
– Commercial FEM Packages
High-Performance FE Software, IPSAP
Research Trend of Virtual Design and Development
Conclusion
Contents
http://aeroguy.snu.ac.kr3/52
Computers have been widely used in structural engineering for:
– Structural analysis– Computer-aided design and drafting (CADD)– Report preparation
Typical computer usage by an engineer:– Word-processing– Preparation of tender documents and engineering drawings– Small and intermediate computations– Analysis of structures– Design work– Data reduction and storage– Software development– Email– Etc.
Introduction
http://aeroguy.snu.ac.kr4/52
Introduction of Structural Analysis
Computational Structural Analysis : The use of computerized methods to predict the response,
performance, failure and service life of structures and materials under various types of loading conditions
The role of Computational Structural Analysis– Allow the simulation of the behavior complex systems beyond
the reach of analytic theory.– Provide detailed design information in a timely fashion.– Enhance our understanding of engineering systems by
expanding our ability to predict their behavior.– Provide the ability to perform multidisciplinary design
optimization.– Increase competitiveness and lower design/production costs.
http://aeroguy.snu.ac.kr5/52
Introduction of Structural Analysis
구조해석은 흔히들 생각하는 다리와 건물의 구조를 해석하는
토목공학분야뿐만 아니라 항공우주공학 , 기계공학 , 선박해양공학 ,
전자공학 등의 다양한 분야에서 기계적 요소들로 이루어진 구조물의
해석까지 포함
구조해석에서 유한요소 해석법 (FEM:Finite Element Method) 이 가장
보편적으로 사용되는 방법 .
http://aeroguy.snu.ac.kr6/52
Korea market share of CAE in 2004 (45 million $)
CAD & Graphics
OS % of automotives
SC2005 (Top500), ‘Top20Auto Survey of HPC Installations in
the Automotive’
Introduction of Structural Analysis
Current Market for CAE Software– Growth of CAE on industrial field– Especially, structural analysis has largest percentage(50%) of it.– This grow up over time going. In Korea, CAE market in 2005 grew
16% larger than that in 2004.
the expectation ofstructural analysis software market
http://aeroguy.snu.ac.kr7/52
Matrix method : Martin(1966), Meek(1971), Wilson(1960) Terminology of Finite Element : Clough(1960) Extended to all kinds of problems described as variational formulation : Zien
kiewicz Development of efficient finite elements, nonlinear and dynamic analysis
: Oden, Bathe, Huges, Zienkiewicz, Belytschko, Crisfield et al Commercial FEA packages : NASTRAN(1963), ABAQUS(1978), ANSYS(1970) Related Industry :
Manufacturing/Machinery, Automotives, Rail/Transportation, Aerospace/Defense, Consumer/Electronics Products, Medical/Biomechanics, Rubber/Sealing
History of Finite Element Analysis
Introduction of Structural Analysis
http://aeroguy.snu.ac.kr8/52
Iterative method for sparse system– Iterative computations of matrix-vector operations– Jacobi algorithm, Gauss-Seidel algorithm, Conjugate Gradient Method, D
DM(FETI), etc.– Converging speed affected by matrix condition
Operation count can not be estimated beforehand– Easy to parallelize efficiently
Direct method for sparse system– Based on Gauss elimination (LU factorization)– Operation counts determined by matrix size and non-zero pattern (mesh c
onnectivity) Operation count can be estimated beforehand
– Band, skyline, frontal, multifrontal solver, etc.– Numerical robustness, Multiple RHS– Difficult to parallelize efficiently
Introduction of Structural Analysis
http://aeroguy.snu.ac.kr9/52
세계적 최신 전산 해석 프로그램의 개발 및 적용 사례
EU• Dassault 사 Falcon 7x• AirBus 사 가상구조시험
일본•Adventure 프로젝트 •GeoFEM
미국• 각종 유명 상용코드 독점• SALINAS 프로젝트
Introduction of Structural Analysis
http://aeroguy.snu.ac.kr10/52
Large Scale Parallel Structural Analysis Code
SALINAS project - USA– 미국 에너지성의 ASCI 프로젝트의 일환– Developed by Sandia National Laboratory in 1999– 1~10 억 자유도를 필요로 하는 매우 복잡한 구조물의 응력 , 진동 , 과도응답 유한요소
모델에 대한 확장성이 강한 계산 도구의 제공을 목적– Implicit Solver 를 기반으로 하여 수천개 이상의 프로세서로 구성된 ASCI 시스템에서 활용– DDM 에 기반을 둔 Multigrid 알고리듬과 coarse auxiliary 알고리듬과 같은 Multilievel iterati
ve scheme 을 참고한 FETI-DP 알고리듬을 이용– Scalability 를 중시하여 1,000 여개 계산 노드를 가지는 ASCI Red, white 등의 시스템에서
순환적으로 운용
http://aeroguy.snu.ac.kr11/52
Large Scale Parallel Structural Analysis Code
ADVENTURE Project - JAPAN– ADVanced ENgineering analysis Tool for Ultra large REa
l world– Development of Computational Mechanics System for L
arge Scale Analysis and Design– 1997 ~ 2002– 목표 : 슈퍼 컴퓨터 (MPP, PC Cluster) 로 천만 ~ 일억
자유도를 가지는 임의의 모델 형상을 1 시간 ~ 하루 정도의 시간으로 해석 가능
– 약 20 여개의 pre-processing, post-processing 모듈을 구성
Pantheon Model(1.5M DOF) Solid Analysis Fluid Analysis
http://aeroguy.snu.ac.kr12/52
Large Scale Parallel Structural Analysis Code
GeoFEM - JAPAN– Parallel FE Solid Earth Simulator– 1997 ~ 2003– Localized operation & optimum data structures for mass
ively parallel computation– Pluggable design– Platform : linear solver, I/O, visualization
GeoFEM Platform
A test dataset on the ES with 5,886,640 unstructured elements
Geodynamo process and fluid dynamics in the Earth’s outer core
Modeling of Philippine Sea plate boundary
http://aeroguy.snu.ac.kr13/52
Commercial FEA Packages
MSC NASTRAN– Developed by NASA as analysis tools for
the structural analysis of spacecraft. (1963) and managed by MSC
– Through 40 years of R&D, MSC/NASTRAN has been regarded as a standard analysis system in most area of industry.
– Capable of linear static analysis, buckling analysis, vibration and thermal analysis.
– Sparse matrix solver, Automated Component Modal Synthesis
– Analysis results of aerospace structural parts are used as the certification of quality.
Certificated by FAA (USA)
< Structural analysis of VAN >
Turbine blade thermal stress analysis
Stress analysis of Car Bumper
FE model vibration analysis
stress analysis nonlinear analysis
http://aeroguy.snu.ac.kr14/52
Commercial FEA Packages
MSC NASTRAN - Parallel Performance
출처 : www.mscsoftware.com , Ver. : 2004
http://aeroguy.snu.ac.kr15/52
Commercial FEA Packages
ABAQUS– Developed by Hibbitt, Karlsson & Sorrensen in 19
78– In 2005, Dassault Systems(CATIA) acquired ABAQ
US : SIMULIA– Linear and nonlinear structural analysis– Multifrontal solver, Block Lanczos eigen solver– Vectorized Explicit Time Integration for the dynami
c analysis– Conduction, convection and heat transfer proble
m– Analysis of offshore structure
wave-induced inertial force, buoyant force and drag of fluid
Stress analysis of airplane engine
http://aeroguy.snu.ac.kr16/52
Commercial FEA Packages
ABAQUS - Parallel Performance
출처 : www.abaqus.com , Abaqus ver. 6.6
E1: Car crash(274,632 elements)
E2: Cell phone drop (45,785 elements)
E3: Sheet forming (34,540 elements)
E4: Projectile penetration (237,100 elements)
단위 :sec
http://aeroguy.snu.ac.kr17/52
Commercial FEA Packages
– Developed by John Swanson in 1970– Utilized in conceptual design of the
product and the manufacturing process– Provides general graphic utilities– Various analysis utilities
Basic structural analysis, CFD, Electro-magnetic analysis
Thermal stress, Acoustic analysis, Piezoelectric analysis
Multi-physics– AI*NASTRAN solver
Wavefrontal solver based on sparse matrix solver,
Substructuring analysis option for large structures
– Block Lanczos eigen solver– Distributed Pre-conditioned Conjugate
Gradient (DPCG) Distributed Jacobi Conjugate Gradient (DJCG)
Engine analysis
Infrared camera analysis
http://aeroguy.snu.ac.kr18/52
Commercial FEA Packages
- Parallel Module
The solvers are:- Distributed Domain Solver (DDS) - Distributed Jacobi Conjugate Gradient (DJCG) - Algebraic Multigrid (AMG) - Distributed Pre-conditioned Conjugate Gradient (DPCG)
출처 : www.ansys.com , ANSYS ver. 10.0
http://aeroguy.snu.ac.kr19/52
Comments– Most of commercial FEA packages use direct method : multifrontal
(ABAQUS), sparse matrix solver (NASTRAN),
Sparse Matrix, Frontal Solver (ANSYS) Commercial packages need to guarantee the end users the practicality and
reliability Practicing engineers do feel comfortable with the direct method However, the parallel performance of these packages are very poor. ANSYS is trying to add the iterative solver optionally in new version of the c
ode : an alternative method to increase the parallel performance.
Commercial FEM Packages
http://aeroguy.snu.ac.kr20/52
IPSAP : Internet Parallel Structural Analysis Program– General purpose FEA program– Generality, Single CPU & Parallel Performance– Written by C and C++
Performance : Faster than commercial softwares like MSC/Nastran and ABAQUS, etc
High-Performance FE Software, IPSAP
IPSAP/EXPLICIT
VIBRATION ANALYSIS
STRESS ANALYSIS
High-Performance High-Performance Parallel SoftwareParallel Software
Grand Challenge Applications (Large Grand Challenge Applications (Large Scale)Scale)
High-Performance Hardware High-Performance Hardware (Supercomputer, Clusters, GRID)(Supercomputer, Clusters, GRID)
http://aeroguy.snu.ac.kr21/52
High-Performance FE Software, IPSAP
IPSAP : Standard– Linear Static, Vibration Analysis : open on WEB
– Nonlinear, Thermal Analysis : under development
– FE Model : 8 node solid, 4 node solid, 4 node plane, 3 node plane, 2 node beam, Rigid body element
– Nodal force, Acceleration, Temperature load
– Multifrontal Linear Equation solver, Lanczos Eigenvalue extractor
– Library : BLAS(Basic Linear Algebra Subroutine), LAPACK(Linear Algebra Package), METIS
– MPP Parallelization
http://aeroguy.snu.ac.kr22/52
IPSAP : Explicit– Explicit Time Integration, Automatic Time Step Control – Elastic, Orthotropic, Elastoplastic, Johnson-Cook– EOS (Equation of State) : Polynomial Model, JWL, Grüneisen– FE Model : 8 node Hexahedron, 4 node BLT Shell
1 point integration with Hourglass Control– Object Stress Update : Jaumann rate stress update– Artificial Bulk Viscosity– Contact Treatment :
Contact Search : Bucket Sorting Master-Slave Algorithm, Penalty Method Single Surface Contact (or Self Contact)
– Element Erosion and Automatic Exterior contact surface update– MPP Parallelization
High-Performance FE Software, IPSAP
http://aeroguy.snu.ac.kr23/52
Procedure for modified multifrontal solver
Step1-2 Using data structure of Element connectivity
Step3-4 Element Computation is smeared in this step computed using the memory hierarchy
Optimized for finite element method
Step1.
Domain partitionin
g
Step2.
Symbolic factorizatio
n
Step3.
Numerical factorizatio
n
Step4.
Triangular solve
IPSAP – Multifrontal Solver
http://aeroguy.snu.ac.kr24/52
Domain partitioning with graph partitioning– Converting the FEM mesh into graph data
– Various graph building scheme WEM (Weighted Edge Mapping) WEVM (Weighted Edge and Vertex Mapping) I-WEVM (Iterative Weighted Edge and Vertex Mapping)
– Dividing the graph into k parts Graph regularity checking Exact spectral algorithm implemented State-of-the-art techniques incorporated
– METIS 4.0
– ParMETIS 3.1
IPSAP – Multifrontal Solver
http://aeroguy.snu.ac.kr25/52
Symbolic factorization– elimination ordering from partitioned graph(mesh)– front matrix size estimation
Core memory usage is known before real factorization Floating point operation count is estimated
1 2 5 6
3 4 7 8
9 10 13 14
11 12 15 16
1 23
4 567
Domain Order Factorization Order
IPSAP – Multifrontal Solver
http://aeroguy.snu.ac.kr26/52
Numerical factorization– Serial stage : domains are merged with factorized domains– Automatic Matrix assembly
– Operations are performed on dense frontal matrices
Hierarchical memory architecture of modern computers can be fully utilized
21 5 6 7 843
Elimination Tree
1 2
3
4 5
6
7
IPSAP – Multifrontal Solver
http://aeroguy.snu.ac.kr27/52
Parallel Stage : Distributed memory parallelization
– Merging makes the distributed frontal matrix– Factorization is performed with distributed matrixProc 0 Proc 1
Proc 2 Proc 3 Proc 2,3
Proc 0,1 Proc 0,1,2,3
FactorizationFactorization FactorizationFactorization
– 2 dimensional processor map is used
p0
p1
p2
p3
p0
p1
p2
p3
IPSAP – Multifrontal Solver
http://aeroguy.snu.ac.kr28/52
Parallel Stage : Distributed memory parallelization– Block cyclic distribution with 2 dimensional processor map
P 3P 3P 0P 0 P 2P 2P 1P 1
Block CyclicBlock Cyclic
– Owner of sub-matrix is dependent on ordering index– Matrix re-distribution is performed by one-to-one communication– pBLAS & SCALAPACK cannot handle variable block size
Block size is not fixed
p0
p1
p2
p3
IPSAP – Multifrontal Solver
http://aeroguy.snu.ac.kr29/52
Large-scale eigen analysis of 3D complex structures– Finite element method – Prediction of dynamic stability of structures– Up to millions of DOF (Degree of Freedom)– Huge-size computing/resources required– Repetition of linear equation solving
– Feasible algorithm : Block Lanczos Eigenvalue Solver
Equipped with Efficient Direct Equation Solver
IPSAP – Block-Lanczos Eigensolver
http://aeroguy.snu.ac.kr30/52
Block Lanczos algorithm with multifrontal solver– Use of Lanczos method with shift and inverting technique
for eigen solution
– Most of operations in Lanczos steps are required in solution procedure for (K - M)-1 and M inner product
– Efficient direct equation solver is needed for the Lanczos process
– Multiple RHS (Right Hand Side ) operation is needed for the block Lanczos process
(K - M) x= 0 (K - M)-1 Mx = x
= shift , =(shifted eigenvalue) -1
IPSAP – Block-Lanczos Eigensolver
http://aeroguy.snu.ac.kr31/52
Block Lanczos Iteration with MFS
Uj = MVj
(K- M)Wj = Uj
W’j = Wj - Vj-1 BTj-1
Cj = VTj MW’j
W’’j = W’j - Vj Cj
W’’j = Vj+1 Bj : QR factorization
Multifrontal Solver Effetive Mass Multiplication
GEQRF inPLASC
IPSAP – Block-Lanczos Eigensolver
http://aeroguy.snu.ac.kr32/52
Block version of CGS2 : classical Gram-Schmidt with reorthogonalization
0,..., 1for i n
**i jw W
0,1for k 1: 1 ( )
1: 1 1i k Ti j i j w
B V M
1: 1 ( )1: 1 1
i ki j i jw w V B
(1)i Ti j w wB M
(1)1 / ij i jw V B
(0) (1)j j j B B B
IPSAP – Block-Lanczos Eigensolver
http://aeroguy.snu.ac.kr33/52
ISSUE
(1) Increasing Efficiency of
Contact Force Vector Calculation
(2) Increasing Efficiency of
Internal Force Vector Calculation
na
n
nt 2/1nt 1nt 2/3nt
2/1 nt
1 nt
2/1nv
2/1n
2/1n
1nd
1nx
1n
1na
1int
nF 1ncontF 1n
extFSubroutine InternalForce
Subroutine
ContactForce
na
n
nt 2/1nt 1nt 2/3nt
2/1 nt
1 nt
2/1nv
2/1n
2/1n
1nd
1nx
1n
1na
1int
nF 1ncontF 1n
extFSubroutine InternalForce
Subroutine
ContactForce
Contact/Impact Analysis– Nonlinear explicit time integration– Contact search
IPSAP – IPSAP/Explicit
http://aeroguy.snu.ac.kr34/52
1. Each processor computes internal forces of own nodes
2. Commuication and addition for interface nodes (Swap,Add)
- unstructured efficient communication is implemented
1 2 3
4 5 6
7 8 9
Parallelization of Internal Force
IPSAP – IPSAP/Explicit
http://aeroguy.snu.ac.kr35/52
Define 3D box
Slave node updateContact Force
computed in each processor
Communication of Contact Force
Communication of slave nodes’
coordinates
Parallelization of Contact Force
IPSAP – IPSAP/Explicit
http://aeroguy.snu.ac.kr36/52
Hardware Software
Unit Node
CPUIntel Xeon
2.2/2.4/2.8/3.0 GHzOS
Windows Adv. Server 2000
Redhat Linux 9.0RAM DDR ECC 3GB/6GB
HDD IDE 80GB/160GB
Compilergcc-3.3 compilerIntel 8.0 compilerVisual Studio 6.0M/B
E7500/7501 Dual M/B
Total CPU520 CPUs
(2.2/256, 2.4/112, 2.8/64, 3.0/88)
MPILAM/MPI – 7.0.6MPICH – 1.2.5.2
MPI/Pro, NT-MPICH
Total Node 260 NodesJob
schedulerOpen PBS, Condor
Total Memory/Storage
1.02 GB / 25 TBGrid
MiddlewareGlobus 2.4
Network Gigabit Ethernet : Intel NIC e1000 /Fast Ethernet - 7 NFS Server
performance1.283 Tflops (Rmax)2.5 Tflops (Rpeek)
Local Gigabit
Local Fast
NFS & Gateke
eper
External Network
Rack ( 20 Node )
Rack-20 Node & Multi Trunking (4 GB Uplink) -Nortel 380-24T (Giga) & Intel 24T (Fast)
Gigabit Ethernet- Nortel 5510-48T
Fast ethernet- Intel 24T
Performance of IPSAP
Computing Environment– PEGASUS System
http://aeroguy.snu.ac.kr37/52
IPSAP Stress AnalysisSerial performance comparison
with NASTRAN 70.7 and ABAQUS 6.3– 32x32x32 hexagonal elements (DOFs = 107,811)
305
112 93
331
147203
1,345
0
200
400
600
800
1000
1200
1400
1600
Alpha EV67 (667MHz) IBM Power4 1.3GHz Intel Xeon 2.4GHz (Linux)
CPU
TIM
E(S
econd
) IPSAP ABAQUS NASTRAN
2.1 Gflops
Performance of IPSAP
http://aeroguy.snu.ac.kr38/52
0
100
200
300
400
500
600
32x32x32(107811 DOF)
2x128x128(149769 DOF)
2x2x8192(221211 DOF)
Tim
e(se
cond
) IPSAP(CPU TIME)
IPSAP(ELAPSED TIME)
NASTRAN(CPU TIME)
NASTRAN(ELAPSED TIME)
ABAQUS(CPU TIME)
ABAQUS(ELAPES TIME)
2.6 Gflops
IPSAP Stress AnalysisSerial performance comparison
with MSC/NASTRAN 2004 and ABAQUS6.4– PC : Pentium-4(northwood), 3GHz, 1G memory
Performance of IPSAP
http://aeroguy.snu.ac.kr39/52
IPSAP Vibration AnalysisSerial performance comparison
with MSC/NASTRAN 2004 and ABAQUS 6.4– PC : Pentrium-4, 3GHz, 1G memory
0
500
1000
1500
2000
2500
32x32x32(107811 DOF)
2x128x128(149769 DOF)
2x2x8192(221211 DOF)
Tim
e (
second)
IPSAP (elapsed)ABAQUS (elapsed)NASTRAN (elapsed)
Performance of IPSAP
http://aeroguy.snu.ac.kr40/52
NASTRAN ABAQUS IPSAP
Performance of IPSAP
IPSAP Vibration Analysis : Cycloidal Blade Model– Pentium IV 3.2GHz, 2.0 GB RAM, Windows XP– Elapsed time (30 modes extracted)
IPSAP : 2855 sec, NASTRAN2004 : 3251 sec, ABAQUS 6.4 : 4870 sec
47.854Hz (1st mode) 167.09Hz (3rd mode)
48.566Hz (1st mode)175.07Hz (3rd mode)
48.015Hz(1st mode)169.29Hz (3rd mode)
http://aeroguy.snu.ac.kr41/52
IPSAP Stress Analysis– Scalability test in Pegasus system
– 2D Mesh topology
No. of CPUs
MeshNumber of Unknowns
Operation counts
Performance
(GFLOPS)
Scaled Speedu
p
1 100x100x1 5.65E+9 6.06E+4 1.0 1.0
4 200x200x1 5.08E+10 2.41E+5 4.1 4.1
16 400x400x1 4.69E+11 9.62E+5 12.1 12.1
64 800x800x1 4.10E+12 3.84E+6 35.1 35.1
256 1600x1600x1 3.88E+13 1.54E+7 111.3 111.3
Specification of data for 2-D scalability test and results
0 50 100 150 200 2500
50
100
150
200
250
300
Sp
ee
d-u
p
Np
Ideal IPSAP
Performance of IPSAP
http://aeroguy.snu.ac.kr42/52
IPSAP Stress Analysis – Scalability test in Pegasus system – 3D Mesh topology
Specification of data for 3-D scalability test and results
1 40x40x40 201,720 8.11E+11 2.1 1.0
4 50x50x50 390,150 3.06E+12 8.2 3.8
16 64x64x64 811,200 1.33E+13 25.3 11.8
64 80x80x80 1,574,640 5.05E+13 65.5 30.6
256 100x100x100 3,060,300 1.92E+14 216.0 100.9
No. ofCPUs
Performance(GFLOPS)
ScaledSpeedup
MeshNumber ofUnknowns
Operationcounts
0 50 100 150 200 2500
50
100
150
200
250
300
Spe
ed-u
p
Np
Ideal IPSAP
Performance of IPSAP
http://aeroguy.snu.ac.kr43/52
0 100 200 300 400 5000
100
200
300
400
500
Spee
d-up
Number of CPUs
Ideal IPSAP
1 40x40x40 201,720 3.7 1.0
4 50x50x50 390,150 15.6 4.3
16 64x64x64 811,200 48.6 13.3
64 80x80x80 1,574,640 114.0 31.1
256 100x100x100 3,060,300 350.0 95.6
512 128x128x128 6,390,144 664.0 181.4
512 160x160x160 12,442,080 770.0 210.4
No. ofCPUs
Performance(GFLOPS)
ScaledSpeedup
MeshNumber ofUnknowns
IPSAP Stress Analysis– Scalability test – Computing Environment : IBM p690+ (power 4 1.7GHz)– 3D Mesh Topology
Performance of IPSAP
http://aeroguy.snu.ac.kr44/52
0 1 2 3 4 5 6 7 8 90
1
2
3
4
5
6
7
8
9
Spee
d-up
Number of CPUs
Ideal ABAQUS(48x48x48) IPSAP(48x48x48) IPSAP(32x32x32)
No. of CPUs
IPSAP (D-MFS) [32x32x32]IPSAP(D-MFS) D-MFS
[48x48x48]ABAQUS [48x48x48]
(DOF=107,811) (DOF=352,947) (DOF=352,947)
Elapsed time Speedup Elapsed time Speedup Elapsed time Speedup
1 112 sec 1.0 1159 sec 1.0 1345 sec 1.0
2 57 sec 2.0 585 sec 2.0 710 sec 1.9
4 32 sec 3.5 306 sec 3.8 485 sec 2.8
8 17 sec 6.6 152 sec 7.6 468 sec 2.9
IPSAP Stress Analysis– Parallel performance comparison with ABAQUS– IBM Power4 1.3GHz system
Performance of IPSAP
http://aeroguy.snu.ac.kr45/52
IPSAP Vibration Analysis : Simple wing structure– Parallel performance comparison with NASTRAN– PEGASUS Cluster– Distributed memory parallel – 4 node shell elements– 0.5 million DOF
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 180
2
4
6
8
10
12
14
16
Spee
d-U
p
Number of CPUs
Ideal IPSAP NASTRAN
CPU IPSAPNASTRA
N
1 214 sec 327 sec
2 114 sec 213 sec
4 63 sec 177 sec
8 39 sec 112 sec
16 24 sec 104 sec
Solution time only
Performance of IPSAP
http://aeroguy.snu.ac.kr46/52
NCPU
IPSAP/Explicit ( Ncycles = 507) LS-DYNA ( Ncycles = 457)
Grind Time(nano sec) Speedup
ElapsedTime**
Grind Time(nano sec) Speedup
ElapsedTime**
2 2260 2.00 90.5 hr 2270 2.00 81.6 hr
4 1140 3.98 45.5 hr 1295 3.51 46.4 hr
8 575 7.90 22.9 hr 623 7.28 22.4 hr
16 287 15.8 11.5 hr 316 14.4 11.3 hr
32 147 31.3 5.8 hr 163 27.9 5.8 hr
64 73.3 62.0 2.9 hr 92 49.4 3.3 hr
IPSAP/Explicit– Taylor Impact Test– Comparison with LS-DYNA 970– PEGASUS Cluster– Distributed Memory Parallel– 10.0 Million DOF
Performance of IPSAP
http://aeroguy.snu.ac.kr47/52
Mild Steel Sphere :
diameter : 6.35mm
mass : 1.04g
Mild Steel Plate : 50mm x 40mm
thickness : 1.5 mm
Impact Velocity : 610m/s@60degree
Termination Time : 50 micro seconds
Material Model : Johnson-Cook
IPSAP/Explicit– Oblique Impact of Metal Sphere– PEGASUS Cluster– Distributed Memory Parallel
Performance of IPSAP
1 2 4 8 16 32 64 1281
2
4
8
16
32
64
128
Spe
ed U
p
NCPUs
FE+FE comm. Contact Total Ideal
Sphere : 21,600 elementsPlate : 7,488 elementsTotal : 29,088 elements 33,329 nodes 99,987 DOF
http://aeroguy.snu.ac.kr48/52
홈페이지 : http://ipsap.snu.ac.kr– Modules included : Stress analysis, vibration analysis– Elements : solid, shell, beam– Downloadable IPSAP executables
Windows, Linux, OS-X Serial, parallel version
released IPSAP
http://aeroguy.snu.ac.kr49/52
AIRBUS – Aircraft Virtual Structural Testing– 항공기 전기체 가상구조시험
Virtual Design Development
에어버스 가상구조시험 체계 계획 (2005 년 8 월 ) 가상구조시험의 멀티 스케일 해석 접근
http://aeroguy.snu.ac.kr50/52
Virtual Design Development
Boeing– “Virtual Mockup facilities the exploration of a larger design
solution space, at the same time that it helps catch problems before they become very expensive. This enabled Boeing’s 777 program to achieve unprecedented levels of rework reduction, product quality and customer satisfaction.”
William A. McNeelySenior Principal Scientist
Boeing Information and Support Services
Boeing 777Virtual Reality Application
http://aeroguy.snu.ac.kr51/52
NASA– 항공우주비행체의 개발에 걸리는 시간과 비용의 절감 및 안전성이
높은 비행체를 개발 ATED(Analytical Tools and Environments for Design) IITS(Integrated Instrumentation and Testing Systems)
– NASA 내에서 보유하고 있는 항공우주 비행체 설계에 관한 여러 가지 분야의 개발 프로그램들이 연동을 위한 환경 제공
Virtual Design Development
ATED 연구팀의 최적 항공기 설계를 위한 개념도
http://aeroguy.snu.ac.kr52/52
Development of Large Scale Parallel Structural Analysis Code
– SALINAS in USA
– ADVENTURE, GeoFEM in Japan Development and Improvement of High-Performance and General Purpose Structural Analy
sis Program, IPSAP– Multi-frontal Solver (Stress Analysis)
– Block-Lanczos Solver (Vibration Analysis)
– Nonlinear Explicit Time-Integration Solver (IPSAP/Explicit)
– Better Serial/Parallel Computing Performance, Compared with Commercial FE Softwares
Virtual Design and Development is already part of Structure Analysis Culture.
– Significant achievements already performed in several Industries
– Continuous improvement of Hardware and Software performance
Conclusion