Numerical Study on Ionization Structure and Shock Wave Propagation for Improving Flight Performance of Beaming Propulsion Vehcile

JAXA Supercomputer System Annual Report February 2025-January 2026

Report Number: R25EACA17

Subject Category: JSS Inter-University Research

Responsible Representative: Masayuki Takahashi, Associate Professor, Tohoku University
Contact Information: Masayuki Takahashi, Tohoku University(masayuki.takahashi.c8@tohoku.ac.jp)
Members: Takumi Hosoya, Masayuki Takahashi, Sakira Uno

Abstract

The objective of this study is to elucidate the mechanism of ionization front propagation induced by high-intensity beams inside beam-propelled rockets and spacecraft.

Reference URL

N/A

Reasons and benefits of using JAXA Supercomputer System

To numerically investigate discharge phenomena induced by high-intensity beams, we perform multiscale, multidimensional simulations that couple electromagnetic wave, plasma fluid, and heavy-ion fluid models. Due to the high computational cost, it is necessary to use a JAXA supercomputer.

Achievements of the Year

We developed a multidimensional computational code that couples beam propagation, plasma fluid, and heavy-ion fluid models, and used it to simulate the plasma front propagation process. It was found that Joule heating causes heavy ions to expand, leading to an increase in the local effective electric field, which in turn induces ionization and sustains the plasma front propagation. Furthermore, since plasma at the cutoff density is generated at the ionization wavefront, a portion of the incident beam is reflected. Numerical simulations have shown that these reflected waves contain internal plasma information that cannot be observed using optical visualization methods such as high-speed cameras; therefore, by observing the scattered waves with antennas such as rectennas, internal diagnostics become possible, as if performing a CT scan of the plasma.

Publications

N/A

Usage of JSS

Computational Information

Process Parallelization Methods: MPI
Thread Parallelization Methods: N/A
Number of Processes: 8 - 960
Elapsed Time per Case: 24 Hour(s)

JSS3 Resources Used

Fraction of Usage in Total Resources*1(%): 0.05

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	451810.05	0.47
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	0.00	0.00
/data and /data2	0.00	0.00
/ssd	0.00	0.00

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.