Analysis for Integration of G-HAB ECLSS

JAXA Supercomputer System Annual Report February 2024-January 2025

Report Number: R24EAE30300

Subject Category: Space Exploration

Responsible Representative: Norihito Tsuji, Human Spaceflight Technology Directorate, Lunar Gateway Habitation Project Team
Contact Information: Ryosuke Takahashi(takahashi.ryohsuke@jaxa.jp)
Members: Kenji Kano, Masaru Saijo, Daisuke Sugawara, Ryosuke Takahashi

Abstract

"Gateway" is the manned base to be constructed in lunar orbit as a relay base for sustained lunar surface exploration activities, in the international space exploration plan "Artemis Project". Space Agencies participating in the ISS project are mainly involved, and they share the development of each module and equipment. In the future, 4 astronauts are scheduled to stay Gateway for about 30 days a year, and it is expected that it will also be used as a base for manned exploration of Mars (Moon to Mars). Japan is mainly in charge of providing the Environmental Control and Life Support System (ECLSS) in the International Habitation Module (I-Hab). ECLSS includes equipment for controlling air circulation, air pressure, oxygen supply, temperature and humidity, and for removal of CO2 and toxic gases. In addition to ECLSS, Japan will also provide batteries to be used in the Gateway modules (I-Hab, Mini Habitat (HALO)), internal/external cameras of the I-Hab, and pumps to circulate the coolant of Thermal Control System (TCS) in I-Hab. In addition to the above, which will lead to future manned exploration and ground technology, the mission will also transport research equipment and tools (Extra-Vehicular Activity (EVA) suits, and research instruments) needed for lunar surface activities, as well as supplies to provide food, clothing and shelters for astronauts by the Gateway resupply vehicle.

Reference URL

Please refer to https://www.exploration.jaxa.jp/assets/img/program/Leaflet_Gateway_A4.pdf .

Reasons and benefits of using JAXA Supercomputer System

The Gateway, which will be placed into lunar orbit, has strong resource constraints (Launch Mass etc.). So unlike ISS, it is considered to outfit the various equipment in an exposed state without cover panel, and it will bring a very complex internal shape. In addition, I-Hab module is integrated by ESA, and there is no available module including mockup in Japan. Thus, the verification of ECLSS functions and performance will largely depend on analysis, and the timing of demonstration will be limited in almost the final phase of development.

Air circulation analysis, oxygen mixing and diffusion analysis etc. will be required. However, due to the above situation, the analysis needs to be done with quite complex shape, and it requires a very large computational resource. In addition, if a risk becomes apparent in the final phase, the impact will be difficult to accept. From those perspectives, it is considered that performing accurate analysis in early phase using the JAXA Supercomputer System (JSS3) will play an important role in completing the G-HAB project in success.

Achievements of the Year

Trial analysis of oxygen mixing and diffusion (multiple gases, unsteady state) using JSS3 was carried out for the I-Hab module and ECLSS equipment, which are entering the detailed design phase. As a result, a major issue regarding oxygen mixing that could not be found by the single gas steady analysis using a simplified module was identified, and countermeasures are currently being considered and discussed in cooperation with ESA.

Publications

N/A

Usage of JSS

Computational Information

Process Parallelization Methods: MPI
Thread Parallelization Methods: Automatic Parallelization
Number of Processes: 180
Elapsed Time per Case: 500 Hour(s)

JSS3 Resources Used

Fraction of Usage in Total Resources*1(%): 0.00

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	0.00	0.00
TOKI-GP	0.00	0.00
TOKI-XM	0.00	0.00
TOKI-LM	0.00	0.00
TOKI-TST	364.57	0.01
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	1470.00	0.99
/data and /data2	91860.00	0.44
/ssd	15060.00	0.81

Archiver Resources
Archiver Name	Storage Used (TiB)	Fraction of Usage*2(%)
J-SPACE	0.00	0.00

*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.