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Research of Lattice Boltzmann Method

JAXA Supercomputer System Annual Report April 2019-March 2020

Report Number: R19ETET17

Subject Category: Skills Acquisition System

PDF available here

  • Responsible Representative: Takashi Aoyama, Aeronautical Technology Directorate, Numerical Simulation Research Unit
  • Contact Information: Takashi Ishida, Aeronautical Technology Directorate, Numerical Simulation Research Unit(ishida.takashi@jaxa.jp)
  • Members: Daichi Asaoka, Senju Fujii

Abstract

The research objective is to implement Cumulant LBM for collision operator and validate it in terms of the solution accuracy, stability, and cost for high-Reynolds number flow. In addition, the source code of implemented Cumulant LBM is tuned aimed for fast computation.

Reference URL

N/A

Reasons and benefits of using JAXA Supercomputer System

The computational cost of unsteady flow simulation by LBM is very high.

We use JSS2 to reduce the computational time by paralleization.

Achievements of the Year

Cumulant LBM was implemented to current our code and validated through the comparison with SRT and Cascaded LBM in terms of solution accuracy, stability, and cost. In addition, due to the code tuning by writting down matrix calclation and SIMD, multiple relaxation model such as Cascaded LBM and Cumulant LBM can compute at 1.7 times the cost of SRT model.

Annual Reoprt Figures for 2019

Fig.1: Example of SIMD for collision operator

 

Annual Reoprt Figures for 2019

Fig.2: Comparison of CPU time after code tuning

 

Publications

– Non peer-reviewed papers

1) Takashi Ishida, Daichi Asaoka, Masaharu Kameda, Unsteady flow simulation around an airfoil with low-speed and high angle-of-attack conditions by Lattice Boltzmann Method, 33th CFD Symposium

Usage of JSS2

Computational Information

  • Process Parallelization Methods: N/A
  • Thread Parallelization Methods: OpenMP
  • Number of Processes: 1
  • Elapsed Time per Case: 1000 Second(s)

Resources Used

 

Fraction of Usage in Total Resources*1(%): 1.28

 

Details

Please refer to System Configuration of JSS2 for the system configuration and major specifications of JSS2.

Computational Resources
System Name Amount of Core Time
(core x hours)
Fraction of Usage*2(%)
SORA-MA 11,348,171.01 1.38
SORA-PP 15,318.40 0.10
SORA-LM 0.00 0.00
SORA-TPP 0.00 0.00

 

File System Resources
File System Name Storage Assigned
(GiB)
Fraction of Usage*2(%)
/home 495.91 0.41
/data 49,018.88 0.84
/ltmp 5,859.38 0.50

 

Archiver Resources
Archiver Name Storage Used
(TiB)
Fraction of Usage*2(%)
J-SPACE 0.00 0.00

*1: Fraction of Usage in Total Resources: Weighted average of three resource types (Computing, File System, and Archiver).

*2: Fraction of Usage:Percentage of usage relative to each resource used in one year.

JAXA Supercomputer System Annual Report April 2019-March 2020