JAXA Supercomputer System Annual Report February 2025-January 2026

Report Number: R25EDA101R21

Subject Category: Aeronautical Technology

PDF (to be added)

• Responsible Representative: Atsushi Kanda, Program Director of Aviation Technology, Aviation Technology Directorate
• Contact Information: Takehisa Takaishi, FQUROH-2 Project Team (Airframe Noise Reduction Technology Project Team), Aviation Technology Directorate(takaishi.takehisa@jaxa.jp)
• Members: Takehisa Takaishi, Mitsuhiro Murayama, Yasushi Ito, Takashi Ishida, Yoimi Kojima, Kazuomi Yamamoto, Kentaro Tanaka, Tohru Hirai, Gen Nakano

Abstract

Major airports in Japan are considering increasing the number of takeoffs and landings to meet the projected growth in air travel demand, strengthen their international competitiveness, and enhance passenger convenience. To support this expansion, it is essential to advance technologies that reduce airframe noise—particularly noise generated by high-lift devices and landing gear—so that surrounding communities are not adversely affected. Our approach includes developing a flight-test plan using a commercial aircraft to demonstrate airframe-noise reduction under real operating conditions. In parallel, we have created an 8%‑scale semi‑span wind tunnel model based on NASA's High‑Lift Common Research Model (CRM‑HL) to conduct further demonstrations using a generic aircraft configuration. These efforts represent key steps toward the practical development of effective noise-reduction technologies. We also use computational simulations to confirm the feasibility of noise‑reduction concepts and associated design methods. This computational analysis, based on Large/Detached Eddy Simulations (LES/DES), is used to clarify the mechanisms of noise generation, predict noise levels, and support the design of noise‑reduction devices.

Reference URL

Please refer to https://www.aero.jaxa.jp/eng/research/ecat/fquroh/ .

Reasons and benefits of using JAXA Supercomputer System

The JSS3 has been used to analyze the detailed physics of noise generation and to optimize noise‑reduction designs. The FQUROH project aims to accelerate the technology maturity of airframe noise‑reduction methods by utilizing advanced, large‑scale, high‑fidelity computational simulations on the JSS3's high‑performance computing platform, as well as by demonstrating these high‑fidelity design technologies through flight tests. Thanks to the computational capabilities of the JSS3, it has become possible to design low‑noise devices based on detailed physical insights that are difficult to obtain solely from wind tunnel testing. In addition, the JSS3's large‑capacity hard‑disk and tape storage systems enable both short‑term and long‑term retention of the massive datasets generated by unsteady numerical analyses.

Achievements of the Year

Unsteady CFD simulations were conducted to evaluate the noise generated by the leading‑edge slat, which is a major noise source during the landing approach of commercial aircraft. The slat is equipped with a support mechanism (the slat track) that enables deployment and retraction. This mechanism, however, is known to further complicate the separated flow region that forms beneath the slat, resulting in significant additional noise. In this study, we examined the characteristics of the slat-track noise and methods to reduce it, in combination with noise-reduction design concepts applied to the slat itself. In particular, we focused on differences in the cross‑sectional shape of the slat track and clarified how these geometric variations influence the resulting noise characteristics and the underlying fluid‑dynamic mechanisms (Fig. 1).

Fig.1: Surface pressure‑fluctuation distributions around the slat track before and after its shape modification

Publications

N/A

Usage of JSS

Computational Information

• Process Parallelization Methods: MPI
• Thread Parallelization Methods: N/A
• Number of Processes: 256
• Elapsed Time per Case: 24 Hour(s)

JSS3 Resources Used

Fraction of Usage in Total Resources*1(%): 0.38

Details

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

*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

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

JAXA Supercomputer System Annual Report February 2025-January 2026