Research on the rotorcraft aerodynamics and noise prediction technologies

JAXA Supercomputer System Annual Report February 2025-January 2026

Report Number: R25EDA201G28

Subject Category: Aeronautical Technology

Responsible Representative: YASUE Kanako, Aviation Technology Directorate, Aviation Integration Innovation Hub
Contact Information: IKEDA Tomoaki(ikeda.tomoaki@jaxa.jp)
Members: Hirokazu Higashida, Manabu Hisida, Kenji Hayashi, Tomoaki Ikeda, Masatoshi Kanayama, Yuki Kishi, Hideji Saiki, Kanako Yasue

Abstract

We aim at the development of aerodynamics and noise computation techniques for rotorcrafts by the unstructured-grid CFD code FaSTAR-Move that utilizes an overset moving grid approach. Extracting the unsteady CFD data obtained by FaSTAR-Move onto the noise source control surface defined around rotor blades, noise propagation is analyzed by iAWESOME a fast acoustic-equation solver that can consider noise-shielding effect as a coupled approach.

Reference URL

N/A

Reasons and benefits of using JAXA Supercomputer System

In this research topic, real-scale complicated models must be computed with real flow conditions, which requires large computer resources and is suited to the use of the JAXA supercomputer system.

Achievements of the Year

In this fiscal year, we farther conducted noise simulations on HART-II helicopter model to numerically evaluate Blade-Vortex Interaction (BVI) noise, which is a primary noise of the rotor craft. Especially we focus on the quantitative evaluation of the noise shielding capability of HART-II body by extending the model sting length. The noise source, exported from FaSTAR-Move, is imposed on the control surface placed around the rotor. The noise propagation is computed by iAWESOME in the time-averaged flow field obtained by RANS, with a scattering effect on the HART-II body. The noise carpet of BVISPL clearly shows the acoustic shielding effect by the model sting.

Fig.1: Acoustic pressure distributions of HART-II model by FaSTAR-Move/iAWESOME coupling approach: (a) Baseline model (b) Sting-extended model (Frequency: 20BPF)

Fig.2: BVISPL noise carpet underneath HART-II model: (left) Baseline model (right) Sting-extended model (Unit: [dB])

Publications

- Non peer-reviewed papers

IKEDA Tomoaki, YASUE Kanako, KANAYAMA Masatoshi, "The Noise Propagation Analysis Considering the Acoustic Shielding Effects of the Fuselage of HART-II," the 63rd Aircraft Symposium, 2025.

Usage of JSS

Computational Information

Process Parallelization Methods: MPI
Thread Parallelization Methods: N/A
Number of Processes: 2496
Elapsed Time per Case: 442 Hour(s)

JSS3 Resources Used

Fraction of Usage in Total Resources*1(%): 0.60

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	15678886.17	0.71
TOKI-ST	31680.96	0.03
TOKI-GP	0.00	0.00
TOKI-XM	0.00	0.00
TOKI-LM	313.90	0.02
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	1024.00	1.64
/data and /data2	102400.00	0.67
/ssd	30720.00	1.87

Archiver Resources
Archiver Name	Storage Used (TiB)	Fraction of Usage*2(%)
J-SPACE	6.42	0.02

*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)	109.19	0.08

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