JAXA Special Publication JAXA-SP-19-003E

Research on future space transportation technology
Report Number: R18EG3103
Subject Category: Research and Development
URL: https://www.jss.jaxa.jp/en/ar/e2018/9134/
Responsible Representative
Susumu Hasegawa, Research Unit IV, Research and Development Directorate, JAXA
Contact Information
Susumu Hasegawa, Research Unit IV, Research and Development Directorate, JAXA
(hasegawa.susumu@jaxa.jp)
Members
Susumu Hasegawa, Toshihiko Munakata, Masaharu Takahashi, Masaaki Fukui
Abstract
Mainly two topics, aiming at the development of the space transport system in the future are studied.
Assuming the flight demonstration, the ejector design that maximizes the air suction performance is examined.
Numerical computations are conducted to search for designs that increase combustion pressure while maintaining
suction performance and the experiments are conducted in joint research with Tokai University and Chubu
University.
Experiments will be conducted in the ISAS / JAXA wind tunnel taking into consideration the effects ofspaceplane engine thrust generation and interaction with the airframe, and analysis of longitudinal aerodynamic
characteristics and analysis of stability will be conducted jointly with Muroran Institute of Technology and ChubuUniversity.

Reasons for using JSS2
Ejector design techniques require the computation of the combustible gases resulting from the combustion of
hybrid rockets. In the computation of the combustion, it is necessary to perform a large-scale numericalcomputation because it is essential to calculate many chemical species. In addition, since the number of
combustion tests of hybrid rocket is limited, optimization is required for the design of the ejector configuration byperforming CFD, which requires large-scale computation.
Furthermore, regarding aerodynamic characteristics of spaceplane which mounted airbreathing engine, it isrequired to obtain aerodynamic characteristics parametrically by several spaceplane configurations, and largescale calculation is essential. For the above reasons, the use of the super computer system JSS2 is required for thesuccess of the present research program.

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JAXA Supercomputer System Annual Report (April 2018-March 2019)

Achievements of the YearThe goal is to establish ejector jet technology in use of the unburned fuel of the hybrid rocket engine. As
preparation for the experiments planned at Tokai University, to improve the suction performance, the test resultsof last year were analyzed by CFD. In the last year’s model, it was found that Fabri choking has occurred, whichhinders the improvement of suction performance. In this year, the design of the new ejector is devised to avoid it
and confirmed that the suction performance reaches the maximum amount of air in our experiments (Fig. 1-2).
Wind tunnel tests at ISAS/JAXA were conducted in consideration of the effects of engine thrust generation andthe interaction with the airframe to analyze longitudinal aerodynamic characteristics and stability. Although theanalysis of the test results of last year was carried out, in the case of no gas injection from the engine, the agreement
between the experiment and the computation is good. However, in the case of gas injection, it is considered that
there is an influence of the hose which supply the nitrogen because the deviation is multiplied. Furthermore, inthis fiscal year, transonic tests were conducted when the steering angle was changed, and the phenomena wereclarified by CFD (Fig. 3-4).

Fig. 1: Ejector experimental apparatus using hybrid rocket

Fig. 2: Numerical Mach number distribution around ejector－271－This document is provided by JAXA.

JAXA Special Publication JAXA-SP-19-003E

Fig. 3: Numerical vorticity distribution around spaceplane

Fig. 4: Comparison of experimental and numerical values of drag coefficient
Publications- Peer-reviewed papers
Susumu Hasegawa, et al., “Preliminary Numerical Simulation of Flow around Spaceplane for Airframe Engine
Integration,” “Transactions of JSASS, Aerospace Technology Japan,” Online ISSN: 1884-0485, ISSN-L: 18840485- Non peer-reviewed papers
1) Susumu Hasegawa, “Studies of the configurations for improvement of the annular ejector performance,” the50th Fluid Dynamics Conference/the 36th Aerospace Numerical Simulation Symposium, Miyazaki, July, 2018.
2) Yoshimasa Nishimura, et al. “Aerodynamic Characteristics of a Rocket-based Combined Cycle Spaceplane,”the 16 th HASTIC Technology Conference,. Sapporo, March, 2019.
3) Susumu Hasegawa, et al., “Flow Analysis around Spaceplane for Airframe Engine Integration by CFD” to bepresented at ISTS 2019, Fukui, Japan.
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JAXA Supercomputer System Annual Report (April 2018-March 2019)4) Yoshimasa Nishimura, et al., “Aerodynamic Characteristics of a Rocket-based Combined Cycle Spaceplane”
to be presented at ISTS 2019, Fukui, Japan.
- Oral Presentations
1) Susumu Hasegawa, “Studies of the configurations for improvement of the annular ejector performance,” the50th Fluid Dynamics Conference/the 36th Aerospace Numerical Simulation Symposium, Miyazaki, July, 2018.
2) Yoshimasa Nishimura, et al. “Aerodynamic Characteristics of a Rocket-based Combined Cycle Spaceplane,”the 16 th HASTIC Technology Conference,. Sapporo, March, 2019.
3) Susumu Hasegawa, et al., “Flow Analysis around Spaceplane for Airframe Engine Integration by CFD” to bepresented at ISTS 2019, Fukui, Japan.
4) Yoshimasa Nishimura, et al., “Aerodynamic Characteristics of a Rocket-based Combined Cycle Spaceplane”
to be presented at ISTS 2019, Fukui, Japan.
- Other
Patent application for “invention of ejector device”

Usage of JSS2
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Computational Information
Process Parallelization Methods

MPI

Thread Parallelization Methods

OpenMP

Number of Processes

36 - 256

Elapsed Time per Case

500 Hour (s)Resources Used
Fraction of Usage in Total Resources*1 (%): 0.08
Details
Computational Resources
System NameAmount of Core Time(core x hours)

Fraction of Usage*2 (%)

SORA-MA

226,677.16

0.03

SORA-PP

91,465.31

0.73

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

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JAXA Special Publication JAXA-SP-19-003E

File System Resources
File System Name

Storage Assigned (GiB)

Fraction of Usage*2 (%)

/home

2.67

0.00

/data

3,125.00

0.06/ltmp

390.63

0.03

Archiver Resources
Archiver Name

Storage Used (TiB)

J-SPACE

Fraction of Usage*2 (%)
0.40

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.

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