SlideShare a Scribd company logo
1 of 15
Download to read offline
Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.)
Masashi Imano (OCAEL Co.Ltd.)
Optimization of parameter settings
for GAMG solver in simple solver
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
Test cluster condition
• Hardware: SGI Altix ICE8200

• CPU: Intel Xeon X5365 3.00GHz 4cores x 2

• Node: 16 nodes

• Memory: 16GB/node (No swap memory)

• Interconnect: InfiniBand DDR

• OS: SUSE LINUX ENTERPRISE SERVER 10.3

• MPI:
✓ SGI MPT (1.2.6)
Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.)
“Guidebook for Practical
Applications of CFD
to Pedestrian Wind
Environment around Buildings”
Working Group in Architectural Institute of Japan
Web site (in Japanese and English)( in Japanese)
Akashi Mochida, Yoshihide Tominaga, et al.
Guideline for Practical Applications
Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.)
Case A
(2:1:1 shape)
Case B
(4:4:1 shape)
Case C
(Simple blocks)
Case D
(High-rise bldg.)
Case E
(Niigata)
Case F
(Shinjuku, Tokyo)
Benchmark tests
Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.)
Mesh
Cartesian mesh

(snappyHexMesh)

2.2 millions
Inflow
Interpolate from wind
tunnel results
Top & Side
wall
Zero gradient
Ground and
bldg. wall
Generalized log law

for a smooth wall
Turbulence
model
Standard k-epsilon
Advection
scheme
Upwind
Algorithm SIMPLE (simpleFoam)
Wind direction NNE
Building
complexes with
simple building
shape in actual
urban area
(Niigata)
Case E - Calculation condition
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
Accelerate incompressible solver
• CPU time of linear solver for pressure is dominant:

✓ Many nodes : PCG is faster

✓ Not so many nodes : GAMG is faster

➡ Need to optimize of parameter for GAMG
T2K at The University of Tokyo
Node: 16 cores
Interconnect: Myrinet 2.5GB/s X 2

Solver: ChannelFoam

Mesh: 256x256x256

Pre-conditioner for GAMG: DIC
Better
Worse
PCG
is
faster
GAMG
is
faster
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
GAMG
Geometric agglomerated algebraic multi-grid solver
(Generalised geometric-algebraic multi-grid in Userguide)
http://www.lrr.in.tum.de/Par/appls/apps/amg.html
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
Geometric agglomeration process
Tim Behrens: OpenFOAM's basic solvers for linear systems of equations Solvers, preconditioners, smoothers,
PhD course in CFD with OpenSource software, Technical University of Denmark, February 18, 2009
Merge
Finest grid (Lv.1) Coarse grid (Lv.2)
agglomerator faceAreaPair;

mergeLevels 1;
Coarsest grid (Lv.3)
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
Parameter settings for AMG solver
smoother GaussSeidel, DIC, DICGaussSeidel; // GaussSeidel is
usually best

directSolveCoarsest false, true; // false: Use ICCG/BICCG for
coarsest grid, true: Solve directly in coarsest grid

agglomerator faceAreaPair, algebraicPair; // faceAreaPair is usually
better than algebraicPair

mergeLevels 1, 2, 3, ..; // Usually 1 is better. For simple meshes
setting 2 could be better.

nPreSweeps 0, 1, 2, ..; // Number of pre-smoothing sweeps

nPostSweeps 0, 1, 2, ..; // Number of post-smoothing sweeps

nFinestSweeps 0, 1, 2,..; // Number of smoothing sweeps on finest
mesh

nCellsInCoarsestLevel 1, 2, ..; // Number of cells in coarsest level
mesh
system/fvSolution:
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
Study about nCellsInCoarsestLevel
smoother GaussSeidel, DIC, DICGaussSeidel; // GaussSeidel is
usually best

directSolveCoarsest false, true; // true: Use ICCG/BICCG for
coarsest grid, false: Solve directly in coarsest grid

agglomerator faceAreaPair, algebraicPair; // faceAreaPair is usually
better than algebraicPair

mergeLevels 1, 2, 3, ..; // Usually 1 is better. For simple meshes
setting 2 could be better.

nPreSweeps 0, 1, 2, 3, ..; // Number of pre-smoothing sweeps

nPostSweeps 0, 1, 2, 3, ..; // Number of post-smoothing sweeps

nFinestSweeps 0, 1, 2, 3,..; // Number of smoothing sweeps on finest
mesh

nCellsInCoarsestLevel 8, 16, 32, .., 256, .., 2048, 4096, 8192; //
Number of cells in coarsest level mesh
system/fvSolution:
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
Other calculation conditions
relaxationFactors	
  //	
  0	
  <	
  relaxationFactors	
  <=	
  1	
  
{	
  
	
  	
  	
  	
  p	
  	
  	
  	
  	
  	
  	
  	
  0.3;	
  //	
  for	
  pressure	
  (important)	
  
	
  	
  	
  	
  U	
  	
  	
  	
  	
  	
  	
  	
  0.5;	
  //	
  for	
  velocity	
  vectors	
  (important)	
  
	
  	
  	
  	
  k	
  	
  	
  	
  	
  	
  	
  	
  0.5;	
  //	
  for	
  turbulence	
  kinetic	
  energy	
  
	
  	
  	
  	
  epsilon	
  	
  0.5;	
  //	
  for	
  turbulence	
  kinetit	
  energy	
  
	
  	
  	
  	
  	
  	
  	
  	
  	
  	
  	
  	
  	
  	
  	
  	
  	
  	
  //	
  dissipation	
  rate	
  
}
system/fvSolution:
Solver: simpleFoam

Iitial field conditions: potentialFoam

CPU time: 50 steps (No write result field)
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
Results of speedup ratio
Speedupratio(base256cells)
0.7
0.8
0.9
1
1.1
Number of Cells In Coarsest Level Grid
8 16 32 64 128 256 512 1024 2048 4096 8192
1 node 2 nodes 4 nodes 8 nodes 16 nodes
Better range
for any nodes
Worse
Better
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
Study about nCellsInCoarsestLevel
smoother GaussSeidel, DIC, DICGaussSeidel; // GaussSeidel is
usually best

directSolveCoarsest false, true; // true: Use ICCG/BICCG for
coarsest grid, false: Solve directly in coarsest grid

agglomerator faceAreaPair, algebraicPair; // faceAreaPair is usually
better than algebraicPair

mergeLevels 1, 2, 3, ..; // Usually 1 is better. For simple meshes
setting 2 could be better.

nPreSweeps 0, 1, 2, 3, ..; // Number of pre-smoothing sweeps

nPostSweeps 0, 1, 2, 3, ..; // Number of post-smoothing sweeps

nFinestSweeps 0, 1, 2, 3,..; // Number of smoothing sweeps on finest
mesh

nCellsInCoarsestLevel 8, 16, 32, .., 256, .., 2048, 4096, 8192; //
Number of cells in coarsest level mesh
system/fvSolution:
Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.)
Results of speedup ratio
Speedupratio(basesetting)
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1 node 2 nodes 4 nodes 8 nodes 16 nodes
Worse
Better
mergeLevels 1 2
nPreSweeps 0 1 0 1
nPostSweeps 1 2 3 1 2 3 1 2 3 1 2 3
nFinestSwee 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3
Better
range
for any
nodes
Base
setting
16 nodes
(Speedup ratio could
decrease in many node
parallel calculation
when mergeLevels is 2)
Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.)
Any Questions?

More Related Content

What's hot

OpenFOAM -回転領域を含む流体計算 (Rotating Geometry)-
OpenFOAM -回転領域を含む流体計算 (Rotating Geometry)-OpenFOAM -回転領域を含む流体計算 (Rotating Geometry)-
OpenFOAM -回転領域を含む流体計算 (Rotating Geometry)-Fumiya Nozaki
 
Boundary Conditions in OpenFOAM
Boundary Conditions in OpenFOAMBoundary Conditions in OpenFOAM
Boundary Conditions in OpenFOAMFumiya Nozaki
 
OpenFOAMによる気液2相流解析の基礎と設定例
OpenFOAMによる気液2相流解析の基礎と設定例OpenFOAMによる気液2相流解析の基礎と設定例
OpenFOAMによる気液2相流解析の基礎と設定例takuyayamamoto1800
 
Tutorial to set up a case for chtMultiRegionFoam in OpenFOAM 2.0.0
Tutorial to set up a case for chtMultiRegionFoam in OpenFOAM 2.0.0Tutorial to set up a case for chtMultiRegionFoam in OpenFOAM 2.0.0
Tutorial to set up a case for chtMultiRegionFoam in OpenFOAM 2.0.0ARPIT SINGHAL
 
buoyantBousinessqSimpleFoam
buoyantBousinessqSimpleFoambuoyantBousinessqSimpleFoam
buoyantBousinessqSimpleFoamMilad Sm
 
OpenFOAMソルバの実行時ベイズ最適化
OpenFOAMソルバの実行時ベイズ最適化OpenFOAMソルバの実行時ベイズ最適化
OpenFOAMソルバの実行時ベイズ最適化Masashi Imano
 
OpenFOAMにおける相変化解析
OpenFOAMにおける相変化解析OpenFOAMにおける相変化解析
OpenFOAMにおける相変化解析takuyayamamoto1800
 
OpenFoamの混相流solver interFoamのパラメータによる解の変化
OpenFoamの混相流solver interFoamのパラメータによる解の変化OpenFoamの混相流solver interFoamのパラメータによる解の変化
OpenFoamの混相流solver interFoamのパラメータによる解の変化takuyayamamoto1800
 
OpenFOAMスレッド並列化のための基礎検討
OpenFOAMスレッド並列化のための基礎検討OpenFOAMスレッド並列化のための基礎検討
OpenFOAMスレッド並列化のための基礎検討Fixstars Corporation
 
Turbulence Models in OpenFOAM
Turbulence Models in OpenFOAMTurbulence Models in OpenFOAM
Turbulence Models in OpenFOAMFumiya Nozaki
 
Mixer vessel by cfmesh
Mixer vessel by cfmeshMixer vessel by cfmesh
Mixer vessel by cfmeshEtsuji Nomura
 
ParaviewでのParticle Tracerを用いた可視化
ParaviewでのParticle Tracerを用いた可視化ParaviewでのParticle Tracerを用いた可視化
ParaviewでのParticle Tracerを用いた可視化takuyayamamoto1800
 
OpenFOAM の境界条件をまとめよう!
OpenFOAM の境界条件をまとめよう!OpenFOAM の境界条件をまとめよう!
OpenFOAM の境界条件をまとめよう!Fumiya Nozaki
 
OpenFOAM を用いた Adjoint 形状最適化事例1
OpenFOAM を用いた Adjoint 形状最適化事例1OpenFOAM を用いた Adjoint 形状最適化事例1
OpenFOAM を用いた Adjoint 形状最適化事例1Fumiya Nozaki
 
OpenFOAMの壁関数
OpenFOAMの壁関数OpenFOAMの壁関数
OpenFOAMの壁関数Fumiya Nozaki
 
Adjoint Shape Optimization using OpenFOAM
Adjoint Shape Optimization using OpenFOAMAdjoint Shape Optimization using OpenFOAM
Adjoint Shape Optimization using OpenFOAMFumiya Nozaki
 
OpenFOAM LES乱流モデルカスタマイズ
OpenFOAM LES乱流モデルカスタマイズOpenFOAM LES乱流モデルカスタマイズ
OpenFOAM LES乱流モデルカスタマイズmmer547
 
OpenFOAMのDEM解析のpatchInteractionModelクラスの解読
OpenFOAMのDEM解析のpatchInteractionModelクラスの解読OpenFOAMのDEM解析のpatchInteractionModelクラスの解読
OpenFOAMのDEM解析のpatchInteractionModelクラスの解読takuyayamamoto1800
 
Customization of LES turbulence model in OpenFOAM
Customization of LES turbulence	 model in OpenFOAMCustomization of LES turbulence	 model in OpenFOAM
Customization of LES turbulence model in OpenFOAMmmer547
 

What's hot (20)

OpenFOAM -回転領域を含む流体計算 (Rotating Geometry)-
OpenFOAM -回転領域を含む流体計算 (Rotating Geometry)-OpenFOAM -回転領域を含む流体計算 (Rotating Geometry)-
OpenFOAM -回転領域を含む流体計算 (Rotating Geometry)-
 
Boundary Conditions in OpenFOAM
Boundary Conditions in OpenFOAMBoundary Conditions in OpenFOAM
Boundary Conditions in OpenFOAM
 
OpenFOAMによる気液2相流解析の基礎と設定例
OpenFOAMによる気液2相流解析の基礎と設定例OpenFOAMによる気液2相流解析の基礎と設定例
OpenFOAMによる気液2相流解析の基礎と設定例
 
Tutorial to set up a case for chtMultiRegionFoam in OpenFOAM 2.0.0
Tutorial to set up a case for chtMultiRegionFoam in OpenFOAM 2.0.0Tutorial to set up a case for chtMultiRegionFoam in OpenFOAM 2.0.0
Tutorial to set up a case for chtMultiRegionFoam in OpenFOAM 2.0.0
 
buoyantBousinessqSimpleFoam
buoyantBousinessqSimpleFoambuoyantBousinessqSimpleFoam
buoyantBousinessqSimpleFoam
 
OpenFOAMソルバの実行時ベイズ最適化
OpenFOAMソルバの実行時ベイズ最適化OpenFOAMソルバの実行時ベイズ最適化
OpenFOAMソルバの実行時ベイズ最適化
 
OpenFOAMにおける相変化解析
OpenFOAMにおける相変化解析OpenFOAMにおける相変化解析
OpenFOAMにおける相変化解析
 
OpenFoamの混相流solver interFoamのパラメータによる解の変化
OpenFoamの混相流solver interFoamのパラメータによる解の変化OpenFoamの混相流solver interFoamのパラメータによる解の変化
OpenFoamの混相流solver interFoamのパラメータによる解の変化
 
OpenFOAMスレッド並列化のための基礎検討
OpenFOAMスレッド並列化のための基礎検討OpenFOAMスレッド並列化のための基礎検討
OpenFOAMスレッド並列化のための基礎検討
 
Turbulence Models in OpenFOAM
Turbulence Models in OpenFOAMTurbulence Models in OpenFOAM
Turbulence Models in OpenFOAM
 
Mixer vessel by cfmesh
Mixer vessel by cfmeshMixer vessel by cfmesh
Mixer vessel by cfmesh
 
ParaviewでのParticle Tracerを用いた可視化
ParaviewでのParticle Tracerを用いた可視化ParaviewでのParticle Tracerを用いた可視化
ParaviewでのParticle Tracerを用いた可視化
 
OpenFOAM の境界条件をまとめよう!
OpenFOAM の境界条件をまとめよう!OpenFOAM の境界条件をまとめよう!
OpenFOAM の境界条件をまとめよう!
 
OpenFOAM を用いた Adjoint 形状最適化事例1
OpenFOAM を用いた Adjoint 形状最適化事例1OpenFOAM を用いた Adjoint 形状最適化事例1
OpenFOAM を用いた Adjoint 形状最適化事例1
 
OpenFOAMの壁関数
OpenFOAMの壁関数OpenFOAMの壁関数
OpenFOAMの壁関数
 
Adjoint Shape Optimization using OpenFOAM
Adjoint Shape Optimization using OpenFOAMAdjoint Shape Optimization using OpenFOAM
Adjoint Shape Optimization using OpenFOAM
 
OpenFOAM LES乱流モデルカスタマイズ
OpenFOAM LES乱流モデルカスタマイズOpenFOAM LES乱流モデルカスタマイズ
OpenFOAM LES乱流モデルカスタマイズ
 
Basic openfoa mtutorialsguide
Basic openfoa mtutorialsguideBasic openfoa mtutorialsguide
Basic openfoa mtutorialsguide
 
OpenFOAMのDEM解析のpatchInteractionModelクラスの解読
OpenFOAMのDEM解析のpatchInteractionModelクラスの解読OpenFOAMのDEM解析のpatchInteractionModelクラスの解読
OpenFOAMのDEM解析のpatchInteractionModelクラスの解読
 
Customization of LES turbulence model in OpenFOAM
Customization of LES turbulence	 model in OpenFOAMCustomization of LES turbulence	 model in OpenFOAM
Customization of LES turbulence model in OpenFOAM
 

Viewers also liked

Dynamic Mesh in OpenFOAM
Dynamic Mesh in OpenFOAMDynamic Mesh in OpenFOAM
Dynamic Mesh in OpenFOAMFumiya Nozaki
 
OpenFOAM for beginners: Hands-on training
OpenFOAM for beginners: Hands-on trainingOpenFOAM for beginners: Hands-on training
OpenFOAM for beginners: Hands-on trainingJibran Haider
 
Motor bike by cfmesh
Motor bike by cfmeshMotor bike by cfmesh
Motor bike by cfmeshEtsuji Nomura
 
Basilica cistern, Istanbul
Basilica cistern, IstanbulBasilica cistern, Istanbul
Basilica cistern, Istanbulmhr56
 
quà tặng bộ số để bàn,biểu trưng số kỷ niệm ngày thành lập
quà tặng bộ số để bàn,biểu trưng số kỷ niệm ngày thành lậpquà tặng bộ số để bàn,biểu trưng số kỷ niệm ngày thành lập
quà tặng bộ số để bàn,biểu trưng số kỷ niệm ngày thành lậpNhật Minh
 
Course materials chapter 5 winter 2014
Course materials chapter 5 winter 2014Course materials chapter 5 winter 2014
Course materials chapter 5 winter 2014actus2007
 
06.02.2014 odf ukraine_military_scenario_pl
06.02.2014 odf ukraine_military_scenario_pl06.02.2014 odf ukraine_military_scenario_pl
06.02.2014 odf ukraine_military_scenario_plodfoundation
 
Elektroninio pasto klientu_konfiguravimas
Elektroninio pasto klientu_konfiguravimasElektroninio pasto klientu_konfiguravimas
Elektroninio pasto klientu_konfiguravimasDonatas Bukelis
 
2014 h & f uniteam
2014 h & f   uniteam2014 h & f   uniteam
2014 h & f uniteamah_ape
 
К. Скобеев: "Точки роста проекта без ссылок"
К. Скобеев: "Точки роста проекта без ссылок"К. Скобеев: "Точки роста проекта без ссылок"
К. Скобеев: "Точки роста проекта без ссылок"Скобеев и Партнеры
 
Propel Ad - DDM Alliance Summit Marketing on Facebook
Propel Ad - DDM Alliance Summit Marketing on FacebookPropel Ad - DDM Alliance Summit Marketing on Facebook
Propel Ad - DDM Alliance Summit Marketing on FacebookDDM Alliance
 

Viewers also liked (16)

Dynamic Mesh in OpenFOAM
Dynamic Mesh in OpenFOAMDynamic Mesh in OpenFOAM
Dynamic Mesh in OpenFOAM
 
MSc Presentation.potx
MSc Presentation.potxMSc Presentation.potx
MSc Presentation.potx
 
OpenFOAM for beginners: Hands-on training
OpenFOAM for beginners: Hands-on trainingOpenFOAM for beginners: Hands-on training
OpenFOAM for beginners: Hands-on training
 
Baffle meshing
Baffle meshingBaffle meshing
Baffle meshing
 
Motor bike by cfmesh
Motor bike by cfmeshMotor bike by cfmesh
Motor bike by cfmesh
 
20141213 cf mesh
20141213 cf mesh20141213 cf mesh
20141213 cf mesh
 
Basilica cistern, Istanbul
Basilica cistern, IstanbulBasilica cistern, Istanbul
Basilica cistern, Istanbul
 
Buy Chef Pants
Buy Chef PantsBuy Chef Pants
Buy Chef Pants
 
quà tặng bộ số để bàn,biểu trưng số kỷ niệm ngày thành lập
quà tặng bộ số để bàn,biểu trưng số kỷ niệm ngày thành lậpquà tặng bộ số để bàn,biểu trưng số kỷ niệm ngày thành lập
quà tặng bộ số để bàn,biểu trưng số kỷ niệm ngày thành lập
 
Course materials chapter 5 winter 2014
Course materials chapter 5 winter 2014Course materials chapter 5 winter 2014
Course materials chapter 5 winter 2014
 
06.02.2014 odf ukraine_military_scenario_pl
06.02.2014 odf ukraine_military_scenario_pl06.02.2014 odf ukraine_military_scenario_pl
06.02.2014 odf ukraine_military_scenario_pl
 
Elektroninio pasto klientu_konfiguravimas
Elektroninio pasto klientu_konfiguravimasElektroninio pasto klientu_konfiguravimas
Elektroninio pasto klientu_konfiguravimas
 
2014 h & f uniteam
2014 h & f   uniteam2014 h & f   uniteam
2014 h & f uniteam
 
К. Скобеев: "Точки роста проекта без ссылок"
К. Скобеев: "Точки роста проекта без ссылок"К. Скобеев: "Точки роста проекта без ссылок"
К. Скобеев: "Точки роста проекта без ссылок"
 
Propel Ad - DDM Alliance Summit Marketing on Facebook
Propel Ad - DDM Alliance Summit Marketing on FacebookPropel Ad - DDM Alliance Summit Marketing on Facebook
Propel Ad - DDM Alliance Summit Marketing on Facebook
 
Slide share pagrindai
Slide share pagrindaiSlide share pagrindai
Slide share pagrindai
 

Similar to Optimization of parameter settings for GAMG solver in simple solver, OpenFOAM Study Meeting for beginner@Kanto, 8th Sep. 2012

SGI OpenFOAM Cloud Benchmark Part 2, OpenFOAM Study Meeting for beginner@Kant...
SGI OpenFOAM Cloud Benchmark Part 2, OpenFOAM Study Meeting for beginner@Kant...SGI OpenFOAM Cloud Benchmark Part 2, OpenFOAM Study Meeting for beginner@Kant...
SGI OpenFOAM Cloud Benchmark Part 2, OpenFOAM Study Meeting for beginner@Kant...Masashi Imano
 
Compile ahead of time. It's fine?
Compile ahead of time. It's fine?Compile ahead of time. It's fine?
Compile ahead of time. It's fine?Dmitry Chuyko
 
Copy-Paste and Muons
Copy-Paste and MuonsCopy-Paste and Muons
Copy-Paste and MuonsAndrey Karpov
 
Barker_SIAMCSE15
Barker_SIAMCSE15Barker_SIAMCSE15
Barker_SIAMCSE15Karen Pao
 
SGI OpenFOAM Cloud Benchmark Part 3, OpenFOAM Study Meeting for beginner@Kans...
SGI OpenFOAM Cloud Benchmark Part 3, OpenFOAM Study Meeting for beginner@Kans...SGI OpenFOAM Cloud Benchmark Part 3, OpenFOAM Study Meeting for beginner@Kans...
SGI OpenFOAM Cloud Benchmark Part 3, OpenFOAM Study Meeting for beginner@Kans...Masashi Imano
 
Performance Optimization of CGYRO for Multiscale Turbulence Simulations
Performance Optimization of CGYRO for Multiscale Turbulence SimulationsPerformance Optimization of CGYRO for Multiscale Turbulence Simulations
Performance Optimization of CGYRO for Multiscale Turbulence SimulationsIgor Sfiligoi
 
Parallelization of Coupled Cluster Code with OpenMP
Parallelization of Coupled Cluster Code with OpenMPParallelization of Coupled Cluster Code with OpenMP
Parallelization of Coupled Cluster Code with OpenMPAnil Bohare
 
Choosing Right Garbage Collector to Increase Efficiency of Java Memory Usage
Choosing Right Garbage Collector to Increase Efficiency of Java Memory UsageChoosing Right Garbage Collector to Increase Efficiency of Java Memory Usage
Choosing Right Garbage Collector to Increase Efficiency of Java Memory UsageJelastic Multi-Cloud PaaS
 
Low latency in java 8 v5
Low latency in java 8 v5Low latency in java 8 v5
Low latency in java 8 v5Peter Lawrey
 
SGI OpenFOAM Cloud Benchmark, OpenFOAM Study Meeting for beginner@Kansai, 7th...
SGI OpenFOAM Cloud Benchmark, OpenFOAM Study Meeting for beginner@Kansai, 7th...SGI OpenFOAM Cloud Benchmark, OpenFOAM Study Meeting for beginner@Kansai, 7th...
SGI OpenFOAM Cloud Benchmark, OpenFOAM Study Meeting for beginner@Kansai, 7th...Masashi Imano
 
C++ Data-flow Parallelism sounds great! But how practical is it? Let’s see ho...
C++ Data-flow Parallelism sounds great! But how practical is it? Let’s see ho...C++ Data-flow Parallelism sounds great! But how practical is it? Let’s see ho...
C++ Data-flow Parallelism sounds great! But how practical is it? Let’s see ho...Jason Hearne-McGuiness
 
Incubating Apache Hivemall
Incubating Apache HivemallIncubating Apache Hivemall
Incubating Apache HivemallMakoto Yui
 
Performance tuning jvm
Performance tuning jvmPerformance tuning jvm
Performance tuning jvmPrem Kuppumani
 
Optimizing TSUBAME2.5 Network with Sub-Optimal Infrastructure
Optimizing TSUBAME2.5 Network with Sub-Optimal InfrastructureOptimizing TSUBAME2.5 Network with Sub-Optimal Infrastructure
Optimizing TSUBAME2.5 Network with Sub-Optimal InfrastructureAkihiro Nomura
 
First phase report on "ANALYZING THE EFFECTIVENESS OF THE ADVANCED ENCRYPTION...
First phase report on "ANALYZING THE EFFECTIVENESS OF THE ADVANCED ENCRYPTION...First phase report on "ANALYZING THE EFFECTIVENESS OF THE ADVANCED ENCRYPTION...
First phase report on "ANALYZING THE EFFECTIVENESS OF THE ADVANCED ENCRYPTION...Nikhil Jain
 
Van jaconson netchannels
Van jaconson netchannelsVan jaconson netchannels
Van jaconson netchannelsSusant Sahani
 
ICIAM 2019: Reproducible Linear Algebra from Application to Architecture
ICIAM 2019: Reproducible Linear Algebra from Application to ArchitectureICIAM 2019: Reproducible Linear Algebra from Application to Architecture
ICIAM 2019: Reproducible Linear Algebra from Application to ArchitectureJason Riedy
 
Reproducible Linear Algebra from Application to Architecture
Reproducible Linear Algebra from Application to ArchitectureReproducible Linear Algebra from Application to Architecture
Reproducible Linear Algebra from Application to ArchitectureJason Riedy
 

Similar to Optimization of parameter settings for GAMG solver in simple solver, OpenFOAM Study Meeting for beginner@Kanto, 8th Sep. 2012 (20)

SGI OpenFOAM Cloud Benchmark Part 2, OpenFOAM Study Meeting for beginner@Kant...
SGI OpenFOAM Cloud Benchmark Part 2, OpenFOAM Study Meeting for beginner@Kant...SGI OpenFOAM Cloud Benchmark Part 2, OpenFOAM Study Meeting for beginner@Kant...
SGI OpenFOAM Cloud Benchmark Part 2, OpenFOAM Study Meeting for beginner@Kant...
 
Compile ahead of time. It's fine?
Compile ahead of time. It's fine?Compile ahead of time. It's fine?
Compile ahead of time. It's fine?
 
Copy-Paste and Muons
Copy-Paste and MuonsCopy-Paste and Muons
Copy-Paste and Muons
 
Barker_SIAMCSE15
Barker_SIAMCSE15Barker_SIAMCSE15
Barker_SIAMCSE15
 
SGI OpenFOAM Cloud Benchmark Part 3, OpenFOAM Study Meeting for beginner@Kans...
SGI OpenFOAM Cloud Benchmark Part 3, OpenFOAM Study Meeting for beginner@Kans...SGI OpenFOAM Cloud Benchmark Part 3, OpenFOAM Study Meeting for beginner@Kans...
SGI OpenFOAM Cloud Benchmark Part 3, OpenFOAM Study Meeting for beginner@Kans...
 
Performance Optimization of CGYRO for Multiscale Turbulence Simulations
Performance Optimization of CGYRO for Multiscale Turbulence SimulationsPerformance Optimization of CGYRO for Multiscale Turbulence Simulations
Performance Optimization of CGYRO for Multiscale Turbulence Simulations
 
Parallelization of Coupled Cluster Code with OpenMP
Parallelization of Coupled Cluster Code with OpenMPParallelization of Coupled Cluster Code with OpenMP
Parallelization of Coupled Cluster Code with OpenMP
 
SpeedIT FLOW
SpeedIT FLOWSpeedIT FLOW
SpeedIT FLOW
 
Choosing Right Garbage Collector to Increase Efficiency of Java Memory Usage
Choosing Right Garbage Collector to Increase Efficiency of Java Memory UsageChoosing Right Garbage Collector to Increase Efficiency of Java Memory Usage
Choosing Right Garbage Collector to Increase Efficiency of Java Memory Usage
 
Low latency in java 8 v5
Low latency in java 8 v5Low latency in java 8 v5
Low latency in java 8 v5
 
SGI OpenFOAM Cloud Benchmark, OpenFOAM Study Meeting for beginner@Kansai, 7th...
SGI OpenFOAM Cloud Benchmark, OpenFOAM Study Meeting for beginner@Kansai, 7th...SGI OpenFOAM Cloud Benchmark, OpenFOAM Study Meeting for beginner@Kansai, 7th...
SGI OpenFOAM Cloud Benchmark, OpenFOAM Study Meeting for beginner@Kansai, 7th...
 
C++ Data-flow Parallelism sounds great! But how practical is it? Let’s see ho...
C++ Data-flow Parallelism sounds great! But how practical is it? Let’s see ho...C++ Data-flow Parallelism sounds great! But how practical is it? Let’s see ho...
C++ Data-flow Parallelism sounds great! But how practical is it? Let’s see ho...
 
Incubating Apache Hivemall
Incubating Apache HivemallIncubating Apache Hivemall
Incubating Apache Hivemall
 
Performance tuning jvm
Performance tuning jvmPerformance tuning jvm
Performance tuning jvm
 
Optimizing TSUBAME2.5 Network with Sub-Optimal Infrastructure
Optimizing TSUBAME2.5 Network with Sub-Optimal InfrastructureOptimizing TSUBAME2.5 Network with Sub-Optimal Infrastructure
Optimizing TSUBAME2.5 Network with Sub-Optimal Infrastructure
 
First phase report on "ANALYZING THE EFFECTIVENESS OF THE ADVANCED ENCRYPTION...
First phase report on "ANALYZING THE EFFECTIVENESS OF THE ADVANCED ENCRYPTION...First phase report on "ANALYZING THE EFFECTIVENESS OF THE ADVANCED ENCRYPTION...
First phase report on "ANALYZING THE EFFECTIVENESS OF THE ADVANCED ENCRYPTION...
 
Van jaconson netchannels
Van jaconson netchannelsVan jaconson netchannels
Van jaconson netchannels
 
ICIAM 2019: Reproducible Linear Algebra from Application to Architecture
ICIAM 2019: Reproducible Linear Algebra from Application to ArchitectureICIAM 2019: Reproducible Linear Algebra from Application to Architecture
ICIAM 2019: Reproducible Linear Algebra from Application to Architecture
 
cug2011-praveen
cug2011-praveencug2011-praveen
cug2011-praveen
 
Reproducible Linear Algebra from Application to Architecture
Reproducible Linear Algebra from Application to ArchitectureReproducible Linear Algebra from Application to Architecture
Reproducible Linear Algebra from Application to Architecture
 

Recently uploaded

Carbohydrates principles of biochemistry
Carbohydrates principles of biochemistryCarbohydrates principles of biochemistry
Carbohydrates principles of biochemistryKomakeTature
 
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...Amil baba
 
me3493 manufacturing technology unit 1 Part A
me3493 manufacturing technology unit 1 Part Ame3493 manufacturing technology unit 1 Part A
me3493 manufacturing technology unit 1 Part Akarthi keyan
 
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptxVertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptxLMW Machine Tool Division
 
sdfsadopkjpiosufoiasdoifjasldkjfl a asldkjflaskdjflkjsdsdf
sdfsadopkjpiosufoiasdoifjasldkjfl a asldkjflaskdjflkjsdsdfsdfsadopkjpiosufoiasdoifjasldkjfl a asldkjflaskdjflkjsdsdf
sdfsadopkjpiosufoiasdoifjasldkjfl a asldkjflaskdjflkjsdsdfJulia Kaye
 
Quasi-Stochastic Approximation: Algorithm Design Principles with Applications...
Quasi-Stochastic Approximation: Algorithm Design Principles with Applications...Quasi-Stochastic Approximation: Algorithm Design Principles with Applications...
Quasi-Stochastic Approximation: Algorithm Design Principles with Applications...Sean Meyn
 
CSR Managerial Round Questions and answers.pptx
CSR Managerial Round Questions and answers.pptxCSR Managerial Round Questions and answers.pptx
CSR Managerial Round Questions and answers.pptxssusera0771e
 
Technology Features of Apollo HDD Machine, Its Technical Specification with C...
Technology Features of Apollo HDD Machine, Its Technical Specification with C...Technology Features of Apollo HDD Machine, Its Technical Specification with C...
Technology Features of Apollo HDD Machine, Its Technical Specification with C...Apollo Techno Industries Pvt Ltd
 
Summer training report on BUILDING CONSTRUCTION for DIPLOMA Students.pdf
Summer training report on BUILDING CONSTRUCTION for DIPLOMA Students.pdfSummer training report on BUILDING CONSTRUCTION for DIPLOMA Students.pdf
Summer training report on BUILDING CONSTRUCTION for DIPLOMA Students.pdfNaveenVerma126
 
Guardians and Glitches: Navigating the Duality of Gen AI in AppSec
Guardians and Glitches: Navigating the Duality of Gen AI in AppSecGuardians and Glitches: Navigating the Duality of Gen AI in AppSec
Guardians and Glitches: Navigating the Duality of Gen AI in AppSecTrupti Shiralkar, CISSP
 
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...amrabdallah9
 
Tachyon 100G PCB Performance Attributes and Applications
Tachyon 100G PCB Performance Attributes and ApplicationsTachyon 100G PCB Performance Attributes and Applications
Tachyon 100G PCB Performance Attributes and ApplicationsEpec Engineered Technologies
 
Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...soginsider
 
The relationship between iot and communication technology
The relationship between iot and communication technologyThe relationship between iot and communication technology
The relationship between iot and communication technologyabdulkadirmukarram03
 
cloud computing notes for anna university syllabus
cloud computing notes for anna university syllabuscloud computing notes for anna university syllabus
cloud computing notes for anna university syllabusViolet Violet
 
Engineering Mechanics Chapter 5 Equilibrium of a Rigid Body
Engineering Mechanics  Chapter 5  Equilibrium of a Rigid BodyEngineering Mechanics  Chapter 5  Equilibrium of a Rigid Body
Engineering Mechanics Chapter 5 Equilibrium of a Rigid BodyAhmadHajasad2
 

Recently uploaded (20)

Lecture 2 .pdf
Lecture 2                           .pdfLecture 2                           .pdf
Lecture 2 .pdf
 
Carbohydrates principles of biochemistry
Carbohydrates principles of biochemistryCarbohydrates principles of biochemistry
Carbohydrates principles of biochemistry
 
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
 
Lecture 4 .pdf
Lecture 4                              .pdfLecture 4                              .pdf
Lecture 4 .pdf
 
me3493 manufacturing technology unit 1 Part A
me3493 manufacturing technology unit 1 Part Ame3493 manufacturing technology unit 1 Part A
me3493 manufacturing technology unit 1 Part A
 
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptxVertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
 
sdfsadopkjpiosufoiasdoifjasldkjfl a asldkjflaskdjflkjsdsdf
sdfsadopkjpiosufoiasdoifjasldkjfl a asldkjflaskdjflkjsdsdfsdfsadopkjpiosufoiasdoifjasldkjfl a asldkjflaskdjflkjsdsdf
sdfsadopkjpiosufoiasdoifjasldkjfl a asldkjflaskdjflkjsdsdf
 
Quasi-Stochastic Approximation: Algorithm Design Principles with Applications...
Quasi-Stochastic Approximation: Algorithm Design Principles with Applications...Quasi-Stochastic Approximation: Algorithm Design Principles with Applications...
Quasi-Stochastic Approximation: Algorithm Design Principles with Applications...
 
CSR Managerial Round Questions and answers.pptx
CSR Managerial Round Questions and answers.pptxCSR Managerial Round Questions and answers.pptx
CSR Managerial Round Questions and answers.pptx
 
計劃趕得上變化
計劃趕得上變化計劃趕得上變化
計劃趕得上變化
 
Technology Features of Apollo HDD Machine, Its Technical Specification with C...
Technology Features of Apollo HDD Machine, Its Technical Specification with C...Technology Features of Apollo HDD Machine, Its Technical Specification with C...
Technology Features of Apollo HDD Machine, Its Technical Specification with C...
 
Présentation IIRB 2024 Marine Cordonnier.pdf
Présentation IIRB 2024 Marine Cordonnier.pdfPrésentation IIRB 2024 Marine Cordonnier.pdf
Présentation IIRB 2024 Marine Cordonnier.pdf
 
Summer training report on BUILDING CONSTRUCTION for DIPLOMA Students.pdf
Summer training report on BUILDING CONSTRUCTION for DIPLOMA Students.pdfSummer training report on BUILDING CONSTRUCTION for DIPLOMA Students.pdf
Summer training report on BUILDING CONSTRUCTION for DIPLOMA Students.pdf
 
Guardians and Glitches: Navigating the Duality of Gen AI in AppSec
Guardians and Glitches: Navigating the Duality of Gen AI in AppSecGuardians and Glitches: Navigating the Duality of Gen AI in AppSec
Guardians and Glitches: Navigating the Duality of Gen AI in AppSec
 
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
 
Tachyon 100G PCB Performance Attributes and Applications
Tachyon 100G PCB Performance Attributes and ApplicationsTachyon 100G PCB Performance Attributes and Applications
Tachyon 100G PCB Performance Attributes and Applications
 
Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...
 
The relationship between iot and communication technology
The relationship between iot and communication technologyThe relationship between iot and communication technology
The relationship between iot and communication technology
 
cloud computing notes for anna university syllabus
cloud computing notes for anna university syllabuscloud computing notes for anna university syllabus
cloud computing notes for anna university syllabus
 
Engineering Mechanics Chapter 5 Equilibrium of a Rigid Body
Engineering Mechanics  Chapter 5  Equilibrium of a Rigid BodyEngineering Mechanics  Chapter 5  Equilibrium of a Rigid Body
Engineering Mechanics Chapter 5 Equilibrium of a Rigid Body
 

Optimization of parameter settings for GAMG solver in simple solver, OpenFOAM Study Meeting for beginner@Kanto, 8th Sep. 2012

  • 1. Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.) Masashi Imano (OCAEL Co.Ltd.) Optimization of parameter settings for GAMG solver in simple solver
  • 2. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) Test cluster condition • Hardware: SGI Altix ICE8200 • CPU: Intel Xeon X5365 3.00GHz 4cores x 2 • Node: 16 nodes • Memory: 16GB/node (No swap memory) • Interconnect: InfiniBand DDR • OS: SUSE LINUX ENTERPRISE SERVER 10.3 • MPI: ✓ SGI MPT (1.2.6)
  • 3. Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.) “Guidebook for Practical Applications of CFD to Pedestrian Wind Environment around Buildings” Working Group in Architectural Institute of Japan Web site (in Japanese and English)( in Japanese) Akashi Mochida, Yoshihide Tominaga, et al. Guideline for Practical Applications
  • 4. Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.) Case A (2:1:1 shape) Case B (4:4:1 shape) Case C (Simple blocks) Case D (High-rise bldg.) Case E (Niigata) Case F (Shinjuku, Tokyo) Benchmark tests
  • 5. Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.) Mesh Cartesian mesh (snappyHexMesh) 2.2 millions Inflow Interpolate from wind tunnel results Top & Side wall Zero gradient Ground and bldg. wall Generalized log law for a smooth wall Turbulence model Standard k-epsilon Advection scheme Upwind Algorithm SIMPLE (simpleFoam) Wind direction NNE Building complexes with simple building shape in actual urban area (Niigata) Case E - Calculation condition
  • 6. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) Accelerate incompressible solver • CPU time of linear solver for pressure is dominant: ✓ Many nodes : PCG is faster ✓ Not so many nodes : GAMG is faster ➡ Need to optimize of parameter for GAMG T2K at The University of Tokyo Node: 16 cores Interconnect: Myrinet 2.5GB/s X 2 Solver: ChannelFoam Mesh: 256x256x256 Pre-conditioner for GAMG: DIC Better Worse PCG is faster GAMG is faster
  • 7. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) GAMG Geometric agglomerated algebraic multi-grid solver (Generalised geometric-algebraic multi-grid in Userguide) http://www.lrr.in.tum.de/Par/appls/apps/amg.html
  • 8. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) Geometric agglomeration process Tim Behrens: OpenFOAM's basic solvers for linear systems of equations Solvers, preconditioners, smoothers, PhD course in CFD with OpenSource software, Technical University of Denmark, February 18, 2009 Merge Finest grid (Lv.1) Coarse grid (Lv.2) agglomerator faceAreaPair; mergeLevels 1; Coarsest grid (Lv.3)
  • 9. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) Parameter settings for AMG solver smoother GaussSeidel, DIC, DICGaussSeidel; // GaussSeidel is usually best directSolveCoarsest false, true; // false: Use ICCG/BICCG for coarsest grid, true: Solve directly in coarsest grid agglomerator faceAreaPair, algebraicPair; // faceAreaPair is usually better than algebraicPair mergeLevels 1, 2, 3, ..; // Usually 1 is better. For simple meshes setting 2 could be better. nPreSweeps 0, 1, 2, ..; // Number of pre-smoothing sweeps nPostSweeps 0, 1, 2, ..; // Number of post-smoothing sweeps nFinestSweeps 0, 1, 2,..; // Number of smoothing sweeps on finest mesh nCellsInCoarsestLevel 1, 2, ..; // Number of cells in coarsest level mesh system/fvSolution:
  • 10. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) Study about nCellsInCoarsestLevel smoother GaussSeidel, DIC, DICGaussSeidel; // GaussSeidel is usually best directSolveCoarsest false, true; // true: Use ICCG/BICCG for coarsest grid, false: Solve directly in coarsest grid agglomerator faceAreaPair, algebraicPair; // faceAreaPair is usually better than algebraicPair mergeLevels 1, 2, 3, ..; // Usually 1 is better. For simple meshes setting 2 could be better. nPreSweeps 0, 1, 2, 3, ..; // Number of pre-smoothing sweeps nPostSweeps 0, 1, 2, 3, ..; // Number of post-smoothing sweeps nFinestSweeps 0, 1, 2, 3,..; // Number of smoothing sweeps on finest mesh nCellsInCoarsestLevel 8, 16, 32, .., 256, .., 2048, 4096, 8192; // Number of cells in coarsest level mesh system/fvSolution:
  • 11. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) Other calculation conditions relaxationFactors  //  0  <  relaxationFactors  <=  1   {          p                0.3;  //  for  pressure  (important)          U                0.5;  //  for  velocity  vectors  (important)          k                0.5;  //  for  turbulence  kinetic  energy          epsilon    0.5;  //  for  turbulence  kinetit  energy                                      //  dissipation  rate   } system/fvSolution: Solver: simpleFoam Iitial field conditions: potentialFoam CPU time: 50 steps (No write result field)
  • 12. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) Results of speedup ratio Speedupratio(base256cells) 0.7 0.8 0.9 1 1.1 Number of Cells In Coarsest Level Grid 8 16 32 64 128 256 512 1024 2048 4096 8192 1 node 2 nodes 4 nodes 8 nodes 16 nodes Better range for any nodes Worse Better
  • 13. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) Study about nCellsInCoarsestLevel smoother GaussSeidel, DIC, DICGaussSeidel; // GaussSeidel is usually best directSolveCoarsest false, true; // true: Use ICCG/BICCG for coarsest grid, false: Solve directly in coarsest grid agglomerator faceAreaPair, algebraicPair; // faceAreaPair is usually better than algebraicPair mergeLevels 1, 2, 3, ..; // Usually 1 is better. For simple meshes setting 2 could be better. nPreSweeps 0, 1, 2, 3, ..; // Number of pre-smoothing sweeps nPostSweeps 0, 1, 2, 3, ..; // Number of post-smoothing sweeps nFinestSweeps 0, 1, 2, 3,..; // Number of smoothing sweeps on finest mesh nCellsInCoarsestLevel 8, 16, 32, .., 256, .., 2048, 4096, 8192; // Number of cells in coarsest level mesh system/fvSolution:
  • 14. Aug. 8th 2012 OpenFOAM Study Meeting for beginner @ Kansai Masashi Imano (OCAEL Co. Ltd.) Results of speedup ratio Speedupratio(basesetting) 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1 node 2 nodes 4 nodes 8 nodes 16 nodes Worse Better mergeLevels 1 2 nPreSweeps 0 1 0 1 nPostSweeps 1 2 3 1 2 3 1 2 3 1 2 3 nFinestSwee 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 Better range for any nodes Base setting 16 nodes (Speedup ratio could decrease in many node parallel calculation when mergeLevels is 2)
  • 15. Aug. 26th 2012 OpenFOAM Study Meeting for beginner @ Kanto Masashi Imano (OCAEL Co. Ltd.) Any Questions?