JAXA Supercomputer System Annual Report April 2018-March 2019

Report Number: R18ECMP06

Subject Category: Competitive Funding

PDF available here

• Responsible Representative: Yuko Inatomi, Institute of Space and Astronautical Science, Department of Interdisciplinary Space Science
• Contact Information: Ryoji Takaki(ryo@isas.jaxa.jp)
• Members: Ryoji Takaki, Taku Nonomura, Seiji Tsutsumi, Yuma Fukushima, Soshi Kawai, Ikuo Miyoshi, Satoshi Sekimoto, Hiroshi Koizumi, Tomohide Inari, Ryota Hirashima, Yoshiharu Tamaki, Takuya Karatsu

Abstract

We develop a high-speed/high-precision computational program using a quasi-first principle method, which can faithfully reproduce the actual flight environment to understand the true nature of fluid phenomena. Specifically, we develop a high-precision compressible flow solver with geometric wall models and LES (Large Eddy Simulation) wall models based on hierarchical, orthogonal and equally spaced structured grids.

Reference URL

Please refer to ‘サブ課題D｜重点課題８：近未来型ものづくりを先導する革新的設計・製造プロセスの開発‘.

Reasons for using JSS2

We need large computer like JSS2 because our calculations must be large scale computations. Moreover, JSS2 has a similar architecture to the our target computer called Post-K.

Achievements of the Year

We proceeded with the development of a compressible fluid analysis program FFVHC – ACE using a hierarchical, orthogonal and equally spaced structured grid method. In this fiscal year, a trial calculation for the aircraft of the actual detailed shape (JSM_CRM_LEG model) was performed using the immersed boundary method . Figure 1 is the computational grid for the JSM_CRM_LEG model. Figure 2 shows the object surface of the landing gear expressed in the flow solver. The reproducibility of the object surface is improved as the grid resolution improves. Figure 3 shows the vorticity around the JSM_CRM_LEG model, where Mach number is 0.2, the Reynolds number is 10 6 , and attack angle is 7 degrees. The total number of grid points is about 800 million, of which the number of fluid points is about 600 million.

Fig.1: The hierarchical, orthogonal and equally spaced structured grid around the JSM_CRM_LEG model.

Fig.2: Shape reproducibility of complicated geometry.

Fig.3(video): Flow around the JSM_CRM_LEG model.

Publications

– Oral Presentations

R. Takaki, Toward the achievement of the aerodynamic characteristic evaluation for real configurations and real flight environments of aircraft, 4rd Symposium on Post-K computer Priority Issue 8.

– Other

Ryoji Takaki, How to make an aerospace vehicle with supercomputer !? – Roles of supercomputer in manufacturing – , 13th symposium to know K-computer in Mito – From K-computer to Post-K computer.

Usage of JSS2

Computational Information

• Process Parallelization Methods: MPI
• Thread Parallelization Methods: OpenMP
• Number of Processes: 256 – 600
• Elapsed Time per Case: 120 Hour(s)

Resources Used

Fraction of Usage in Total Resources*1(%): 3.88

Details

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

*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 2018-March 2019