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Numerical investigation of combustible flows using the adaptive mesh refinement (AMR)

JAXA Supercomputer System Annual Report April 2017-March 2018

Report Number: R17EACA35

Subject Category: JSS2 Inter-University Research

PDF available here

  • Responsible Representative: Edyta Dzieminska, Department of Engineering and Applied Sciences, Faculty of Science and Technology, Sophia University
  • Contact Information: Edyta Dzieminska Edyta.d@sophia.ac.jp
  • Members: Edyta Dzieminska, Yuta Aishima, Kota Sato, Yuto Hara, Mitsuharu Morishita, Hajime Sakai, Yuichi Niga, Syota Yamamoto, Xinmeng Tang

Abstract

We mainly do the investigations the behaviors of combustible flows, especially H2/Air and H2/O2 mixtures with high or normal pressures. The interested physical phenomena include the jet flame, hydrogen safety, deflagration to detonation transition (DDT) as well as detonation.

Now well-designed adaptive mesh refinement (AMR) codes for the simulation of combustible flows are being perfected and are used to calculate the hydrogen jet flame and the DDT process. Fundamental mechanism like the gradient mechanism on the onset of detonation in the DDT process will be discussed in details owing to the high resolution by AMR. Engineering Parameters like the how fast/how wide hydrogen would spread can also be analysed as well as the combustible characteristic.

Reference URL

N/A

Reasons for using JSS2

Numerical calculations are used to simulate the combustible flows with AMR which provides local high resolutions. In order to discuss the detailed flame and detonation structures, the flame or detonation fields need to be reproduced by the simulation in 2D or 3D to some extent both in time and space, which are large-scale calculations. Therefore, the supercomputer would be necessary for use to perform such a research. Without it, we cannot get valid data to analyse.

Achievements of the Year

1) AMR program with reaction models is perfected further.

2) Calculated Jet has developed to a penetration distance which is large enough to analyse the jet properties and to start jet flames.

3) Deflagration to detonation transition (DDT) was reproduced in a tube filled with H2/O2 with high resolutions and the fundamental mechanisms of DDT and detonation have been discussed.

4) Four ■ Peer-reviewed papers are composed based on the above results.

Annual Reoprt Figures for 2017

Fig.1: Instantaneous concentrations of hydrogen with jet pressures of 82 MPa on the yz-slice. Black lines present the block boundaries of sketchy AMR meshes. For easier post process, the number of AMR blocks is reduced to 1/4 of that of the full AMR blocks in ac

 

Annual Reoprt Figures for 2017

Fig.2: A spark in the hydrogen jet with a certain location and energy.

 

Annual Reoprt Figures for 2017

Fig.3: Onset of detonation illustrated by the history of density gradient in a tube filled with H2-O2. The spontaneous reaction wave spreads and produces expanded products which results in a surrounding shock wave. Zeldovich gradient mechanism for DDT can be c

 

Publications

■ Peer-reviewed papers

1) Xinmeng Tang, Edyta Dzieminska, Makoto Asahara, A. Koichi Hayashi and Nobuyuki Tsuboi. Numerical investigation of a high pressure hydrogen jet of 82 MPa with adaptive mesh refinement: concentration and velocity distributions. International Journal of Hydrogen Energy 2018 (Accepted).

2) Xinmeng Tang, Edyta Dzieminska, Makoto Asahara, A. Koichi Hayashi and Nobuyuki Tsuboi. Gradient mechanism on the onset of detonation in the deflagration to detonation transition. Submitted to Proceedings of combustion institude as PROCI-S-17-02072.

3) Xinmeng Tang, Edyta Dzieminska, A. Koichi Hayashi, Nobuyuki Tsuboi and Makoto Asahara. Numerical simulation of the auto-ignition and DDT by AMR. Archivum Combustionis 2018 (Resived).

4) Xinmeng Tang, Edyta Dzieminska, Makoto Asahara, A. Koichi Hayashi and Nobuyuki Tsuboi. Investigations of 105 MPa hydrogen jets. To be submitted to Science and Technology of Energetic Materials.

■ Presentations

1) Hayashi Koichi et al. The simulation of high pressure jet flame from a small nozzle. 55th combustion symposium , Toyama, 2017.

Usage of JSS2

Computational Information

  • Process Parallelization Methods: MPI
  • Thread Parallelization Methods: Automatic Parallelizatio
  • Number of Processes: 256 – 2560
  • Elapsed Time per Case: 100.00 hours

Resources Used

 

Fraction of Usage in Total Resources*1(%): 0.12

 

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 1,003,703.34 0.13
SORA-PP 0.00 0.00
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 052.45 0.04
/data 524.52 0.01
/ltmp 10,742.19 0.81

 

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 2017-March 2018