Research of numerical prediction for the flight stability

JAXA Supercomputer System Annual Report February 2024-January 2025

Report Number: R24EDA201G26

Subject Category: Aeronautical Technology

Responsible Representative: Kazuyuki Nakakita, Aeronarutical Technology Directorate, Fundamental research unit
Contact Information: Yoimi Kojima(kojima.yoimi@jaxa.jp)
Members: Hirokazu Higashida, Atsushi Hashimoto, Junpei Kakazu, Yoimi Kojima, Hideji Saiki

Abstract

The flight stability of aircraft is necessary to establish safe flight. We aim to improve the technology level of flight stability prediction through numerical simulation. The numerical method is validated and analyzed for developing better numerical tools.

Reference URL

N/A

Reasons and benefits of using JAXA Supercomputer System

Unsteady simulations required for the stability analysis demand large computational resources and produce much data. JSS allows us to simulate and analysis of numerical results.

Achievements of the Year

To enable rapid prediction of roll instability, a prediction technique based on Global Stability Analysis (GSA) was developed. Using FaSTAR-GSA, a fast analysis tool, flow instabilities were predicted. Analysis of the eigenvalue distribution obtained from GSA (Fig. 1) revealed that under flow conditions where roll instability occurs in experiments, unstable eigenvalues corresponding to the flow field were identified. GSA successfully predicted the flow conditions under which roll instability arises. Furthermore, visualization of the unstable mode (Fig. 2) showed that the flow instability originates near the wingtip of the main wing.

Fig.1: Eigenvalue distributions by GSA

Fig.2: Unstable velocity mode

Publications

- Oral Presentations

Kojima, Hidaka, Nagai, On the transonic roll instability of SDM model, 56th FDC/42nd ANSS, 2D04, 2024.

Usage of JSS

Computational Information

Process Parallelization Methods: MPI
Thread Parallelization Methods: N/A
Number of Processes: 1152 - 3456
Elapsed Time per Case: 300 Hour(s)

JSS3 Resources Used

Fraction of Usage in Total Resources*1(%): 0.98

Details

Please refer to System Configuration of JSS3 for the system configuration and major specifications of JSS3.

Computational Resources
System Name	CPU Resources Used (Core x Hours)	Fraction of Usage*2(%)
TOKI-SORA	26315953.43	1.20
TOKI-ST	29597.34	0.03
TOKI-GP	0.00	0.00
TOKI-XM	10.08	0.00
TOKI-LM	10174.22	0.73
TOKI-TST	0.00	0.00
TOKI-TGP	0.00	0.00
TOKI-TLM	0.00	0.00

File System Resources
File System Name	Storage Assigned (GiB)	Fraction of Usage*2(%)
/home	33.38	0.02
/data and /data2	48157.17	0.23
/ssd	239.05	0.01

Archiver Resources
Archiver Name	Storage Used (TiB)	Fraction of Usage*2(%)
J-SPACE	17.59	0.06

*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.

ISV Software Licenses Used

ISV Software Licenses Resources
	ISV Software Licenses Used (Hours)	Fraction of Usage*2(%)
ISV Software Licenses (Total)	457.15	0.31

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