Gas-liquid two phase flow behabior related to ECLSS

JAXA Supercomputer System Annual Report February 2025-January 2026

Report Number: R25ECWU77

Subject Category: Cooperative Graduate School System

Responsible Representative: Manager of ECLSS, Research Unit II, Aerospace RInsertHereD Directorate, JAXA
Contact Information: Masato Sakurai(sakurai.masato@jaxa.jp)
Members: Yuki Ban, Hikono Furuichi, Motoharu Kusano, Shin Noguchi, Masato Sakurai

Abstract

To advance manned space exploration, we elucidate the behavior of gas-liquid two-phase flow generated during the operation of the Environment Control and Life Support System (ECLSS) in low-gravity environments.

Reference URL

N/A

Reasons and benefits of using JAXA Supercomputer System

Large-scale, high-speed numerical simulations are essential for reproducing complex gas-liquid two-phase flows, and utilizing JSS enables their realization.

Achievements of the Year

To establish a passive gas-liquid separator utilizing wetting properties, we investigated the behavior of gas-liquid two-phase flow within a tube. The results showed that, based on a qualitative comparison with experimental data, the behavior was generally reproduced.

Fig.1: Transportation of liquid within a pipe featuring a teardrop-shaped cross-section.

Fig.2: A circular flow path featuring a teardrop shape.

Fig.3: Behavior of droplets inside the tube. A flow path has formed with gas on the inner wall and liquid on the outer wall.

Publications

N/A

Usage of JSS

Computational Information

Process Parallelization Methods: MPI
Thread Parallelization Methods: OpenMP
Number of Processes: 144 - 324
Elapsed Time per Case: 24 Hour(s)

JSS3 Resources Used

Fraction of Usage in Total Resources*1(%): 0.02

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	0.00	0.00
TOKI-ST	69528.51	0.07
TOKI-GP	0.00	0.00
TOKI-XM	0.00	0.00
TOKI-LM	0.00	0.00
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	2.73	0.01

*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)	0.00	0.00

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