JAXA Supercomputer System Annual Report April 2017-March 2018

Research on the Future Transportation Technology( Integrated Design of Airframe and Engine)
Report Number：R17EG3103
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4436/
Responsible Representative
Kouichi Okita Research and Development Directorate, Unit IV

Contact Information
Susumu Hasegawa hasegawa.susumu@jaxa.jp

Members
Susumu Hasegawa

Abstract
The establishment of technologies for airframe/engine integration of the spaceplane for the realizationof future space transportation technology.

Reasons for using of JSS2
The comparison between the experimental data obtained by wind tunnel tests and the numerical results
were conducted and verified. After the verifications of numerical results, various aerodynamic data which
are difficult to obtain by experiments are computed and analyzed by CFD for the realization of thespaceplane.

Achievements of the Year
Correspondent numerical calculations of spaceplane performed by wind tunnel experiment werecarried out. Comparing the experimental results with the numerical calculation results, computational
results obtained by CFD are in good agreement with experimental results. Furthermore, in order toimprove the spaceplane configuration, the configuration where flow separation was likely to occur was
identified in each flight Mach number. We changed the spaceplane configuration of the second phasespaceplane and conducted the wind tunnel tests in December, 2017. Moreover, the analysis of ejector
experiments was carried out using CFD.

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.1 Numerical Schlieren around the splaceplane for the flight condition of Mach 0.7

Fig.2 Numerical Schlieren around the splaceplane for the flight condition of Mach 0.9

Fig.3 Numerical Schlieren around the splaceplane for the flight condition of Mach 1.1

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.4 Mach number distribution around the ejector (The chamber pressure was 3.0MPa)

Publications
 Peer-reviewed papers
1) Susumu Hasegawa, Takeshi Kanda: "Preliminary Numerical Simulation of Flow around Spaceplane
for Airframe Engine Integration", Transactions of JSASS, Aerospace Technology Japan.
 Non peer-reviewed papers
1) Kanenori Kato, Kouichi Takasaki, Kouichiro Tani, Susumu Hasegawa, Kazuhide Mizobata, andTakeshi Kanda, "Coupled Aerodynamic Characteristics of Airframe and Engine of Space Plane",
31st ISTS, 2017-a-41, Matsuyama, Ehime, Japan. Jun. 2017.
2) Susumu Hasegawa, Kanda Takeshi : Numerical analysis of the flowfield around the spaceplane
tested in the transonic wind tunnel, JSASS Northern Branch 2018 Annual Meeting, Sendai, May.
2018.
 Presentations
1) Susumu Hasegawa, Takeshi Kanda: "Preliminary Numerical Simulation of Flow around Spaceplane
for Airframe Engine Integration ", 31st ISTS, 2017-a-40, Matsuyama, Ehime, Japan. Jun. 2017.
2) Kanenori Kato, , Kouichi Takasaki, Kouichiro Tani, Susumu Hasegawa, Kazuhide Mizobata, andTakeshi Kanda, "Coupled Aerodynamic Characteristics of Airframe and Engine of Space Plane",
31st ISTS, 2017-a-41, Matsuyama, Ehime, Japan. Jun. 2017.
3) Susumu Hasegawa, Kanda Takeshi : Numerical analysis of the flowfield around the spaceplane
tested in the transonic wind tunnel, JSASS Northern Branch 2018 Annual Meeting, Sendai, May.
2018.

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

OpenMP

Number of Processes

32 - 256

Elapsed Time per Case

3.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.04
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

279,219.58

0.04

SORA-PP105.870.00

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

004.45

0.00

/data

4,231.77

0.08

/ltmp

651.040.05

Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

0.57

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

JAXA Supercomputer System Annual Report April 2017-March 2018

Research for Future Transportation System (Research for Scramjet Engine Flow Path)
Report Number：R17EG3104
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4437/
Responsible Representative
Koichi Okita, Research & Development Directorate, Reserch Unit 4

Contact Information
SATO Shigeru ssato@kakuda.jaxa.jp

Members
Shigeru Sato, Toshihiko Munakata, Masaaki Fukui, Masaharu Takahashi

Abstract
The purpose is to investigate the influence of the internal flow path on the engine performance by helpof CFD in the viewpoint of aerodynamics about a scramjet engine which is a main mode of combined
cycle propulsion engine as a reusable space propulsion engine, and to contribute to designing a combined
cycle propulsion engine.
In other words it is to compare the engine results with CFD in order to extract effective factors on
improvement of the engine performance from a lot of experimental results of engine tests stored in
Kakuda Space Center, and to make CFD simulation about a trial engine configuration which is proposed
for engine performance improvement.

Reasons for using of JSS2
In Kakuda Space Center, scramjet engine is being investigated as a main mode of combined cycle
propulsion engine, and a lot of engine performance tests have been made by using Ramjet Engine Test
Facility (RJTF).

It has been found in the tests that the difference of engine inner configuration

produces large difference of thrust performance in the flight condition of Mach 6. CFD simulations arebeing carried out based on the plenty of engine test data stored in Kakuda Space Center about how thedifference of engine inner configuration of main elements of the engine, inlet, isolator, strut and others
influent on the engine performance, and CFD simulations on trial engine configuration not yet tested
are also carried out.
Aerodynamic effects of engine inner configuration are investigated by using CFD, compared with theengine tests, and systematized to prepare basis for decision for designing of combined cycle engine.

JAXA Supercomputer System Annual Report April 2017-March 2018

Achievements of the Year
In order to compare to the result of engine configuration already tested in RJTF (Ramjet Engine Test
Facility) located in Kakuda Space Center, a virtual engine test is being carried out about an improved
engine configuration.

The configuration has a boat-tail strut of which the tail is shortened andsharpened in order to improve the engine thrust performance, though it has the same basic dimension
to the tested engine.

Figure 1 shows the tested engine outline and the both configurations.

The

difference of engine inner quantity is compared between the both engine configurations.
A commercial code ANSYS Fluent is applied to this calculation, and structured grid system is used.
The minimum grid size is set by 0.1mm near the cowl leading edge. The calculation is done in the halfof the engine model assuming mirror condition in the engine symmetric center plane. The number ofgrids at the maximum is 5.03x106. The limiter is the second order accuracy, space integral is AUSM+,
time integral is explicit method, and turbulence model is k-ω model.
For the combustion calculation, a model used here is the model of Fluent including Hydrogen-Oxygen
reaction equation based on the Peterson and Hanson. *)This time Finite Rate Chemistry Model is

employed for the combustion calculation, and the reaction consists of 9 species and 20 elementary
reactions.
Engine air flow condition for calculation is set Mach 5.3 at engine entrance, and total temperature isset at 1500K. RJTF nozzle exit boundary layer (57.9mm thickness / 99.9% of main stream velocity) is
also set in the flows into the engine, which corresponds to the boundary layer on the air frame bottom
surface.
The calculation is performed mainly on JAXA's present Supercomputer System the 2ndGeneration,JSS2. It is used remotely from Kakuda research center.
Figure 3 gives the cowl shock wave in air flow. Fig.3a shows the 5/5-Height strut configuration, andFig.3b shows the Boat-tail strut configuration. In the both configurations it is found that the shock
wave caused at the cowl leading edge clearly expand and reach the top wall. In the comparison between
the both, the shock wave image in the Boat-tail configuration is much clear whose tail part is shortened
and narrowed.
Figure 4 gives the cowl shock wave in combustion oppositely to the above. Fig.4a shows the 5/5Height strut configuration, and Fig.4b shows the Boat-tail strut configuration.

In the bothconfigurations the oblique shock waves caused at the leading edges are seen, and it is found that theshock wave angles increase. Additionally the oblique shocks do not reach the top wall clearly to become
smeared on the way. It seems that the shock wave limit cannot be exactly defined.
It is natural that the pressure and the temperature increase if we have transition to the combustion, sothat sound of speed increases and Mach number decreases. Therefore the angle of oblique shock wave
increase. In addition to that, the present combustion calculation indicated that the shock wave reachpoints are smeared. The flow field changes very much in the area where the shock waves are smeared.
It is needed to research the changed flow field minutely and to fine origins of thrust product. Finding
the origins will make it possible to build methods to create the engine performance.

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.1 Outline of a scramjet engine tested

Fig.2 The 5/5-Height Strut configuration and the Boat-tail Strut configuration

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.3 Cowl shock wave in air flow

Fig.4 Cowl shock wave in combustion

Publications
 Presentations
1) Shigeru Sato, Masaaki Fukui, Takahiro Watanabe, Masaharu Takahashiand Toshihiko
Munakata,Trial for Improvement in Scramjet Engine Performance, AIAA-2018-0889, Kissimmee,
2018.

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

It depends on FLUENT

Thread Parallelization Methods

It depends on FLUENT

Number of Processes

2 - 32Elapsed Time per Case

720.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.03
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

0.00

0.00

SORA-PP

43,179.91

0.54

SORA-LM

48.40

0.02

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

039.07

0.03

/data

397.05

0.01

/ltmp

2,115.89

0.16

Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

0.58

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

JAXA Supercomputer System Annual Report April 2017-March 2018

Future Projection by orbital debris evolutionary model
Report Number：R17EG3105
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4438/
Responsible Representative
Hiroyuki Sugita, Research Unit II, Research and Development Directorate

Contact Information
Masumi Higashide higaside@chofu.jaxa.jp

Members
Takayuki Hirai, Satomi Kawamoto, Masumi Higashide, Yasuhiro Kitagawa, Shuji Abe, Toshiya Hanada

Abstract
Increase of space debris is a problem for reliability of future space activity. JAXA has researched forspace debris removal technology. JAXA and Kyushu university developed an orbital debris evolutionarymodel named NEODEEM to predict numbers of future space objects. Analysis results from NEODEEM
lead which object should be removed.
http://www.kenkai.jaxa.jp/eng/research/debris/debris.html

Reasons for using of JSS2
NEODEEM predicts numbers of long-term future space objects by using Monte-Carlo method. We
expect reduction of computation time.

Achievements of the YearIn this year, preliminary tests for the NEODEEM computation were performed with SORA_PP. An
example of the computation results is shown in Fig. 1. NEODEEM was updated for parallel computing
with OpenMPI. However, the updated model was not employed for this research because repeatabilityof computation results are not assured. Total analysis time was reduced by assigning Monte-Calro run
numbers to multiple cores. We will start NEODEEM computation for future orbital environment analysis
from next year.

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.1 Prediction example of space object number for 100 years

Publications
N/A

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Assigning Monte-Calro run numbers to multiple

Parallelization Methods

cores

Thread Parallelization Methods

N/A

Number of Processes

2 - 10Elapsed Time per Case

60.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.01
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

0.00

0.00

SORA-PP

7,260.68

0.09

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

023.84

0.02

/data

238.42

0.00

/ltmp

4,882.81

0.37

Archiver Resources
Archiver System 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

JAXA Supercomputer System Annual Report April 2017-March 2018

Launch Cost Reduction by Reusing Launch Vehicles
Report Number：R17EG3106
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4439/
Responsible Representative
Koichi Okita, Research Unit IV, Research and Development Directorate

Contact Information
Yoshiki Takama takama.yoshiki@jaxa.jp

Members
Yoshiki Takama, Yoshihisa Aoki

Abstract
This research conducts the study of key technologies applied to future reusable launch vehicles
including long-life rocket engines, lightweight structures, landing guidance, and small experimental
vehicles to validate the technologies.

Reasons for using of JSS2
JSS2 is nessesary for the estimation of aerodynamic performance for a small experimental vehicle.

Achievements of the Year
CFD in the rocket launch phase was conducted as follows:
1) the inside of the rocket nozzle was not calculated.
2) the static pressure, static temperature, and velocity at the nozzle exit were given as the boundary
condition.
The calculation started from the first-order accuracy with the pressure at the nozzle exit one third of
the nominal value. The calculation was gradually accelerated, and successfully converged at the secondorder accuracy with the pressure of the nozzle exit the nominal value.
The axial velocity distribution in the vicinity of the nozzle exit is shown in (Fig. 1). Mach number is0.1. The angle of attack is 0 deg.

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.1 Axial velocity distribution at the lift-off (M=0.1, AOA=0deg)

Publications
N/A

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

N/A

Number of Processes

96

Elapsed Time per Case

300.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.23
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

1,895,520.26

0.25

SORA-PP

113.880.00

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

037.71

0.03

/data

889.02

0.02

/ltmp

634.770.05

Archiver Resources
Archiver System 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

JAXA Supercomputer System Annual Report April 2017-March 2018

Research for Innovation of Rocket Propulsion Engine
Report Number：R17EG3204
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4440/
Responsible Representative
Kouichi Okita (Director), Research and Development Directorate, Unit IV

Contact Information
Susumu Hasegawa hasegawa.susumu@jaxa.jp

Members
Susumu Hasegawa, Toshiya Kimura, Kosei Goto, Atsushi Osada, Masaaki Fukui,
Toshihiko Munakata, Masaharu Takahashi, Kenji

Abstract
Reusable rockets are attracting attention as spacecraft, but their engines are required to have highperformance at a wide range of environmental pressures. In this research, the performance of theaerospike nozzles was investigated by using large-scale numerical fluid dynamics.

Reasons for using of JSS2
The number of experiments is limited, and the data obtained are limited. Therefore, after verificationof numerical results, data which are difficult to obtain by wind tunnel test can be obtained. By using
higher-performance computer, more reliable data can be obtained and the development of nozzle
technology are accelerated.

Achievements of the Year
We began to do research on the aerospike nozzles by using the numerical fluid dynamics. Since it wasnecessary to verify the numerical results with the experimental data obtained, numerical analysis was
conducted the liner aerospike nozzles of 40% and 60% in addition to the 80% linear aerospike nozzle.
Computations were performed and numerical results were obtained when the nozzle pressure ratio(NPR) were 10, 40, 100. Details of the flow analysis are under consideration.

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.1 Mach number distribution around the 80% linear aerospike nozzle, NPR=10

Fig.2 Mach number distribution around the 80% linear aerospike nozzle, NPR=100

Fig.3 Mach number distribution around the 60% linear aerospike nozzle, NPR=10

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.4 Mach number distribution around the 40% linear aerospike nozzle, NPR=10

Publications
N/A

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

N/A

Number of Processes

32 - 256

Elapsed Time per Case

3.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.01
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

6,423.68

0.00

SORA-PP

9.49

0.00

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

100.89

0.07

/data

5,034.13

0.09

/ltmp

11,067.71

0.83

Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

1.15

0.05

*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

JAXA Supercomputer System Annual Report April 2017-March 2018

Study on Future Space Transportation System using Air-breathing Engines
Report Number：R17EG3205
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4441/
Responsible Representative
Kouichi Okita, Research and Development Directorate, Research Unit 4

Contact Information
Masatoshi Kodera kodera.masatoshi@jaxa.jp

Members
Masahiro Takahashi, Masatoshi Kodera, Masaaki Fukui, Toshihiko Munakata,
Masaharu Takahashi, Sadatake Tomioka, Akihiro Shimuta, Takuto Miyaura

Abstract
Recently, reusable rockets have been being studied to reduce the cost of space transportation systems
significantly. However, in order to extend the structural lifetime, it is necessary to operate them withrelatively low engine power, leading to a decrease in launch capability. Therefore, air-breathing engines
such as scramjets and rocket/scram combined cycle engines are promising to compensate the drawback.
By using air in the atmosphere as an oxidizer, the engine becomes highly efficient, and can be expected
to maintain and improve the launch capability even if reused. In this project, we will research and develop
key technology for practical application of the engine.

Reasons for using of JSS2
The following points are raised as problems of engine design by ground experiments. 1) There arelimits to reproducing various airflow conditions from takeoff to hypervelocity ranges. 2) Measured values
are limited and complicated three-dimensional flow structures inside the engine can not be wellidentified. 3) Since the time and cost are limited, it is not easy to change the engine flow pathconfiguration. Therefore, it is indispensable to utilize 3D CFD as a design tool, and a supercomputer isrequired for performing numerous CFD works efficiently.

Achievements of the Year
Subject 1: We continued to conduct a collaborative research with Tohoku University on constructionof simple reaction mechanisms for high molecular hydrocarbon pyrolysis fuel from last year. In this fiscal
year, we applied simple reaction mechanisms for methane / ethylene fuel mixture, which mimics a
cracked jet fuel, to combustion CFD calculations including supersonic combustor flows. The results were

JAXA Supercomputer System Annual Report April 2017-March 2018

compared to those obtained from a detailed reaction mechanism to validate the prediction accuracy androbustness (Fig. 1).
Subject 2: The validation of the combustion CFD using a LS-FLOW solver, which JAXA-JEDI has beendeveloping, was conducted by comparing with the experimental results of the scramjet combustor modelwith gaseous ethelyne as a fuel. Some issures with the current RANS CFD have been clarified (Fig. 2, 3).
The CFD was also applied to the simulation for undergoing combustion experiments with other scramjet
combustor models to help understanding of the experimental results and those to evaluate combustor
performance with modified flow-path design in advance.
Subject 3: RANS CFD on iso-thermal n-octane fuel flow within a tube to evaluate cooling capacity
including thermal decomposition effects, was carried out with turbulence model and reduced chemistry
and the results were compared to experimental results (Fig. 4). The deviation implied deficiencies in
the reduced chemistry and the coking problem in the experiment.

Fig.1 Comparison of CFD results (temperature distributions in supersonic
combustor) obtained from simple and detailed reaction mechanisms((a)-(c) simple mechanisms, (d) detailed mechanism)

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.2 Comparison of the normalized wall pressure distributions and the surface
streamlines on the ethelene-fueled scramjet combustor model obtained by RANS
CFD with different turbulent Schmidt numbers (a) Sct = 0.3 (b) Sct = 0.89

Fig.3 Comparison of the normalized wall pressure distributions and the cross-section
profiles of the normalized pressure, temperature and Mach number obtained by
RANS CFD with different turbulent Schmidt numbers (a) Sct = 0.3 (b) Sct = 0.89

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.4 Comparison between CFD and experiments on endothermic heat
capacity and decomposition rate

Publications
 Non peer-reviewed papers
1) Kodera, M., Tomioka, S., Sasaki, Y., Nakamura, H., and Maruta, K., "Application of Simple Reaction
Mechanisms for CH4/C2H4 Fuel Mixture to Supersonic Combustor Flow Computations,"
Proceedings of the 2018 Annual Meeting, Northern Branch of the Japan Society for Aeronauticaland Space Sciences, 2018.
2) Takahashi, M., Nojima, K., Shimizu, T., Aono, J., and Munakata, T., "Numerical Simulation of
Hydrocarbon-fueled Scramjet Combustor Flows by Using LS-FLOW Solver," Proceedings of the
31st Symposium on Computational Fluid Dynamics, 2017.
3) Shimuta, A., "Research on Endothermic Heat Capacity of Liquid Hydrocarbon Fuel at Supercritical
Condition," Master Thesis, Tohoku University, 2018.
 Presentations
1) Kodera, M., Tomioka, S., Sasaki, Y., Nakamura, H., and Maruta, K., "Application of Simple Reaction
Mechanisms for CH4/C2H4 Fuel Mixture to Supersonic Combustor Flow Computations," The 2018
Annual Meeting, Northern Branch of the Japan Society for Aeronautical and Space Sciences, 2018.
2) Takahashi, M., Nojima, K., Shimizu, T., Aono, J., and Munakata, T., "Numerical Simulation of
Hydrocarbon-fueled Scramjet Combustor Flows by Using LS-FLOW Solver," The 31th Symposiumon Computational Fluid Dynamics, 2017.

JAXA Supercomputer System Annual Report April 2017-March 2018

3) Takahashi, M., Nojima, K., Shimizu, T., Aono, J., and Munakata, T., "Characteristics of Scramjet
Combustor Flows with Ethelyne Fuel," FY29 Space Transportation Symposium, 2018.
4) Miyaura, T., Shimuta, A., Daimon, Y., Tomioka, S., "Research on Endothermic Heat Capacity ofHydrocarbon Fuel at Supercritical Condition," The 2018 Annual Meeting, Northern Branch of theJapan Society for Aeronautical and Space Sciences, 2018.

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

N/A

Number of Processes

32 - 1280

Elapsed Time per Case

72.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 1.10
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

9,220,531.74

1.22

SORA-PP

1,197.46

0.01

SORA-LM

69.74

0.04

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

260.80

0.18

/data

6,000.80

0.11

/ltmp

9,765.63

0.74

Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

2.88

0.12

*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

JAXA Supercomputer System Annual Report April 2017-March 2018

Protection from Space Environment for Expanding Future Space Activities
Report Number：R17EG3210
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4442/
Responsible Representative
Koji Yamanaka, Research and Development Directorate, Research Unit I

Contact Information
Aki Goto goto.aki@jaxa.jp

Members
Aki Goto, Kazunori Shimazaki

Abstract
Our goal is to obtain the technology and knowledge to protect spacecraft and astronauts from harshspace environment for expanding future space activities. Long-term-stay under safer environment is
especially required in the future manned-mission. We, therefore, address the radiation shielding
technology in terms of materials for supporting the safe and long-period manned space activity.

Reasons for using of JSS2
We use JSS2 for PHITS (Particle and Heavy Ion Transport code System) Monte Carlo simulations toestimate shielding effects of materials against space radiations. PHITS Monte Carlo simulations take alarge amount of time when the computational system is large and complex, such as the system simulatedmanned-spaceship structure. Such simulations enable to be run at high speed with statistical accuracy
by using JSS2.

Achievements of the YearIn FY2017, we focused on the galactic cosmic rays (GCR) to be protected in the Beyond Low Earth
Orbit (BLEO) where a manned exploration mission will be conducted in the future, and investigated
optimal shielding design against GCR by conducting calculations for using PHITS (Particle and Heavy
Ion Transport Code System) code.
GCR is high energy particles that flow constantly from outside the solar system, and consists of protons(~ 85%), He nuclei (~ 14%), electrons (~ 1%), and heavy nuclei ranging from lithium to uranium. One
method of reducing the exposure dose is an installation of shielding materials on the spacecraft. In termsof the limitation of transportation weight, a material having high shielding effect per mass is required as

JAXA Supercomputer System Annual Report April 2017-March 2018a shielding material for manned mission. It is known that low atomic number elements have highshielding effect per mass against GCR, and hydrogen (1H) is the most effective. In this study, weinvestigated optimal shielding thickness of polyethylene (PE, (CH2) n) which is an existing shielding
material containing a large amount of hydrogen (hydrogen weight%: 14 wt%). The optimal shielding
thickness of PE is different from the shielding thickness of the spacecraft (mainly composed of Al alloy)
and the dose measurement position (astronauts staying position). In order to investigate the optimal
thickness of PE according to the shielding thickness of the spacecraft, dose calculations were performed
with a simple spherical shell geometry consisting of two layers of Al and PE.
The calculation geometry is shown in Fig. 1. A water sphere (a virtual dosimeter imitating a humanbody) with 30 cm diameter was installed at the center of an Al/PE two layers spherical shell with an innerdiameter of 400 cm. The Al/PE spherical shell was installed so that outside was Al shell. The thickness
of Al was 0 - 50 g/cm2, the thickness of PE was 0 - 60 g/cm2. The interior of the spherical shell (excluding
the water region) was void. The GCR spectra were calculated using the CREME 96 model and are shownin Fig. 2. The solar activity was set as solar minimum (no flare condition), and the position of thespacecraft was set as near-earth interplanetary (no trapped particles, no geomagnetic field). The dose
equivalent in the water sphere, when the GCR radiation source (proton - Ni) was isotropically irradiatedto the Al/PE sphere shell geometry, was calculated by Monte Carlo calculation.
The calculation results are shown in Fig. 3. Because of the installation of PE, the dose equivalent in thewater sphere was reduced by 40% at the maximum (compared with the condition without shielding
material). Regardless of the shielding thickness of Al, the dose equivalent was reduced by about 34 - 40%
by adding PE with about 30 g/cm2thickness. Even if adding PE with over 30 g/cm2 thickness, shielding
effect on dose equivalent nearly unchanged (shielding thickness - dose equivalent curve is almost plateau
at the range of > 30 g/cm2). From this result, the addition of the shielding material with 30 g/cm2 or
more thickness in the BLEO mission is useless in terms of GCR shielding. And, the addition of about 30
g/cm2 PE can be minimized the exposure dose (the achievable minimum value by passive shielding ofrealistic thickness) inside the spacecraft.
The future work is to reflect these results in the shielding guidelines for actual missions. We think thatthe addition of extra shielding materials is not necessarily needed depending on the solar activity, themission duration / place. In the future, we plan to obtain the quantitative data that will contribute toshielding-design optimization guidelines according to the solar activity, the mission duration, and thedesign of the spacecraft.

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.1 Geometry for calculation of effective dose on water sphere
under irradiation of GCR source

Fig.2 GCR spectra (CREME96 model; solar minimum (no flare),near-earth interplanetary, H-Ni)

Fig.3 Dependence of dose equivalent in water sphere on shielding
thickness (under irradiation of GCR)JAXA Supercomputer System Annual Report April 2017-March 2018

Publications
N/A

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

OpenMP

Number of Processes

5 - 24

Elapsed Time per Case

30,000.00 seconds

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.04
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

0.00

0.00

SORA-PP

58,110.50

0.73

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

014.31

0.01

/data

4,978.18

0.09

/ltmp

2,929.69

0.22

Archiver Resources
Archiver System 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

JAXA Supercomputer System Annual Report April 2017-March 2018

Project support using numerical simulation
Report Number：R17EG3211
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4443/
Responsible Representative
Eiji Shima, Research and Development Directorate, Reserch Unit III

Contact Information
Hideyo Negishi negishi.hideyo@jaxa.jp

Members
Takayuki Ito, Ryoji Takaki, Seiji Tsutsumi, Hiroyuki Ito, Taro Shimizu, Junya Aono,
Takanori Haga, Yuhi Morii, Masaharu Abe, Masayuki Kakehi, Mikiroh Motoe, Manabu Hisida,
Hideyo Negishi, Yoichi Ohnishi, Miki Nishimoto, Yu Daimon, Ashvin Hosangadi, Masaaki Ino,
Osamu Fukasawa, Shinji Ohno, Andrea Zambon, Takenori Nakajima, YUKA Akimura,
Takashi Amemiya, Hironori Fujiwara, Hiroumi Tani, Takuya Iimura, Keiichiro Fujimoto,Tetsufumi Ohmaru, AKIKO Kotani, Taroh Fukuda, Mayu Matsumoto, Masashi Toyama,
Hiroaki Amakawa, Katsuyuki Ishibashi, Kei Nishimura, Daiki Muto, Issei Masaie,
Shun Fujimoto, Susumu Sato, Satoshi Ukai

Abstract
Utilize the simulation technology of Reserch Unit III to deal with the technical problem solving incurrent JAXA project, and respond to the request for the project concerning issue. In addition, it realizes"added value (efficiency improvement, high reliability, cost / period reduction, ripple effect, etc.)"
unique to numerical simulation technology.
http://www.kenkai.jaxa.jp/eng/research/software/software.html

Reasons for using of JSS2
In order to respond timely to project requirements, it is necessary to simulate complex geometries ofactual spacecraft and to analyze a large number of conditions in a short period.

Achievements of the Year
With regard to H3, SLIM, HTV-X projects, evaluation of design and risks as well as studies for
improvement were carried out by making full use of the simulation technology of Reserch Unit III andJSS2.

JAXA Supercomputer System Annual Report April 2017-March 2018

Publications
 URLs for the Research Results on the Web1) http://www.kenkai.jaxa.jp/eng/research/software/software.html

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

N/A

Number of Processes

16 - 32

Elapsed Time per Case

30.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 1.17
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

5,738,372.24

0.75

SORA-PP141,174.57

1.77

SORA-LM

0.00

0.00

SORA-TPP

1,035,782.58

30.77

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

6,790.95

4.70

/data

111,422.26

2.06

/ltmp

21,380.23

1.61

Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

111.76

4.81*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

JAXA Supercomputer System Annual Report April 2017-March 2018

Internal flow, combustion, and rotating machinery
Report Number：R17EG3212
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4444/
Responsible Representative
Eiji Shima, Research and Development Directorate, Research Unit III

Contact Information
Taro Shimizu shimizu.taro@jaxa.jp

Members
Hiroaki Amakawa, Takayuki Ito, Ryoji Takaki, Seiji Tsutsumi, Hiroyuki Ito, Taro Shimizu,
Junya Aono, Takanori Haga, Yuhi Morii, Masaharu Abe, Masayuki Kakehi, Mikiroh Motoe,
Manabu Hisida, Hideyo Negishi, Yoichi Ohnishi, Miki Nishimoto, Yu Daimon,
Ashvin Hosangadi, Masaaki Ino, Osamu Fukasawa, Shinji Ohno, Andrea Zambon,
Takenori Nakajima, Yuka Akimura, Takashi Amemiya, Hironori Fujiwara, Hiroumi Tani,
Takuya Iimura, Keiichiro Fujimoto, Tetsufumi Ohmaru, Akiko Kotani, Taroh Fukuda,
Mayu Matsumoto, Masashi Toyama, Katsuyuki Ishibashi, Kei Nishimura, Satoshi Abe,
Daiki Muto, Nozomu Kanno

Abstract
To capture the unsteady phenomena in the liquid rocket engine, combustion large eddy simulations(LES) are carried out, and this evaluation tool is validated by comparing with a sub-scale test. For
thrusters, we build analysis code that can simulate spray combustion mode, first aim at prediction ofsteady state performance.
http://www.kenkai.jaxa.jp/eng/research/software/software.html

Reasons for using of JSS2
Since the flow and combustion in rocket chambers are in a turbulent state and have nonstationary
characteristics, LES analysis is essential. Even in this verification target, analysis calculation of about
several million steps is required for grid of tens of millions of cells, so it is impossible to achieve the target
without using supercomputer.

Achievements of the Year
1. In order to develop and validate numerical analysis code for spray combustion, LES of an ethanol

JAXA Supercomputer System Annual Report April 2017-March 2018

spray combustion burner have been conducted. The diameter of target burner is 10.5 mm, and thenumber of cells of the 3D numerical model is about 15 million. The space has been discretized byfinite volume method. Detailed chemical reaction mechanism constructed with 50 species and 258
reactions has been solved to simulate combustion of ethanol, then ERENA method has been use fortemporal integration of reactions. Figure 1 and 2 show temperature distribution and axial velocity
distribution respectively. As shown in the figures, it is confirmed that the numerical code canreproduce spray combustion qualitatively.
2. Accurate prediction of wall heat flux in combustion chambers using numerical simulations isrequired for engine designs to prevent the serious damage on the chamber wall due to high heatload. Towards the wall heat flux prediction using LES, wall-modeled LES (WMLES) of turbulent
channel flows with heat transfer was performed (Fig. 3). WMLES well predicted velocity andtemperature fields in a wide range of Reynolds numbers up to 100,000 in spite of using a coarser
grid resolution compared with conventional LES.

Fig.1 LES of spray combution, temperature distribution

Fig.2 LES of spray combution, axial velocity distribution

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.3 WMLES of turbulent channel flow with heat transfer. Iso-surface of velocity
colored by temperature is shown.

Publications
 Presentations
1) Motoe, M., "Combustion Simulation for Coaxial Spray Burner Using Detailed Chemical Reaction
Mechanism", The Japan Society of Fluid Mechanics Annual Meeting 2017 (in Japanese).
2) Muto, D., et al., "Preliminary Study on Wall-modeled Large Eddy Simulation of Turbulent Heat
Transfer for Liquid Rocket Engines", 7th European Conference for Aeronautics and Space Sciences,649, Jul., 2017.
3) Negishi, H., et al., "Numerical Anaylsis of Unshrouded Impeller Flowfield in the LE-X Liquid
Hydrogen Pump", 53rd AIAA/SAE/ASEE Joint Propulsion Conference, AIAA paper 2017-4930,
2017.
4) Amakawa, H., et al., "Preliminary Study of Numerical Simulation of Macro-Scale Grease Flow Using
Moving Particle Simulation -Validation between Experiment and CFD for Grease Dam Break -",Tribology Comference 2018 Autumn, 2017 (in Japanese).
5) Negishi, H., et al., "Future Perspectives for Grease Flow Simulation in Ball Bearings to enhanceSpacecraft Lifetime", 31st CFD Symposium, E10-3, 2017 (in Japanese).
6) Daimon, Y., et al., "Heat Flux Estimation on a Chamber Wall of GH2/GOX and GCH4/GOX Single
Element Rocket Combustors", 31st International Symposium on Space Technology and Science,
2017.
7) Daimon, Y., et al., "Numerical Investigation on Effects of Recess Variation upon a GCH4/GOX
Shear Coaxial Combustion Chamber", 31st International Symposium on Space Technology and
Science, 2017.

JAXA Supercomputer System Annual Report April 2017-March 20188) Daimon, Y., et al., "Film Cooling Performance Analysis of a Full-scale Liquid Rocket Engine
Combustion Chamber based on a Coupled Combustion and Heat Transfer Simulation", AIAA Paper,
2017-4919, 2017.
9) Daimon, Y., et al., "Combustion Modeling Study for a GOX-GCH4 Multi-element Combustion
Chamber", Proceedings of the 2017 Summer Program, SFB TRR40, 2017.
10) Shimizu, T., et al., "Evaluation of the Characteristics of Liquid Hydrogen Mixer using LES", 31st
CFD Symposium, E10-2, 2017 (in Japanese).
 Invited lecture1) Negishi, H., "Numerical Modeling of Liquid Rocket Turbopumps", The National DFG SFB TRR40
project, Graduate Program on Launchers and Propulsion, University of Stuttgart, 2018.
2) Daimon, Y., "Numerical and Experimental Study on Small Thruster", The National DFG SFB
TRR40 project, Graduate Program on Launchers and Propulsion, University of Stuttgart, 2018.
3) Daimon, Y., "GCH4/GO2 Rocket Combustor Simulation -Methane vs Hydrogen, Single vs Multi
Element-", DLR Institute of Combustion Technology Seminar, 2018.

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

N/A

Number of Processes

1280 - 2560

Elapsed Time per Case

500.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 6.10
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

49,901,475.03

6.57

SORA-PP

88,645.47

1.11

SORA-LM709.56

0.37

SORA-TPP

85,997.68

9.60

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

6,431.26

4.46

/data

107,461.81

1.99

/ltmp

18,249.37

1.38

Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

122.73

5.28*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

JAXA Supercomputer System Annual Report April 2017-March 2018

Research and Development of Predicting Launch Vehicle Acoustics
Report Number：R17EG3213
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4445/
Responsible Representative
Eiji Shima, Research Unit III, Research and Development Directorate

Contact Information
Seiji Tsutsumi tsutsumi.seiji@jaxa.jp

Members
Ryoji Takaki, Seiji Tsutsumi, Hiroyuki Ito, Taro Shimizu, Junya Aono, Takanori Haga,
Yuhi Morii, Masaharu Abe, Masayuki Kakehi, Mikiroh Motoe, Manabu Hisida,
Yasuhiro Kawashima, Shun Ito, Kazuma Tago

Abstract
Prediction and reduction of the acoustic environment level caused by aeroacoustics of exhaust jet at
lift-off and transonic buffet are required for the development of the next flagship launch vehicle (H3).
Therefore, improve the acoustic analysis tool at the lift-off constructed up to the previous phase, andexpand the range of application, predict the acoustic environment throughout the flight of the launcher/ spacecraft, contribute to the design of low noise launch pad and silent launch vehicle.

Reasons for using of JSS2
It is necessary to carry out LES analysis on the scale of billions of points, and to achieve the targetedfrequency resolution it is essential to havesupercomputer.

Achievements of the YearThrough the subscale model test conducted for the acoustic design of H3 launch vehicle, it wasobserved that acoustic level was reduced by shielding the air intake attached to flame duct. Numerical
study was conducted to investigate the flowfield of air intake and its effect on the acoustic environment
around the launch vehicle. In the subscale model test, clustered liquid rocket engines (LE-9s) locatedat the core of the vehicle were modeled as a single engine. Numerical study was also utilized to evaluate
the difference of acoustic environment between subscale and full-scale acoustic environment. Figure 1
shows the results of the subscale test configuration of the H3-30 having three liquid rockets (LE - 9)without solid rocket boosters.
In the development of H3 launch vehicle, it is considered to cluster the first-stage main engines. A

JAXA Supercomputer System Annual Report April 2017-March 2018

small cold flow test has been carried out so far and observation of Mach wave reduction of free jet byclustering is observed, but the clustering effect under the condition that interacts with the launch pad is
unconfirmed. In the subscale test conducted this fiscal year, acoustic measurements simulating a newlaunch pad geometry were performed, but due to constraints of the feed line system, cluster nozzles weremodeled as a single nozzle of the same exhaust power, and the clustering effect was not evaluated. The
purpose of this numerical analysis is to clarify the clustering effect on the interaction between the exhaust
jet and the launch table (Fig. 2), and the sound pressure level in the vicinity of the launcher for eachclustered and single nozzle configuration is compared using the lift amount as a parameter.As a result of
the analysis, the lift amount that becomes the maximum sound pressure can be parameterized with adimensionless lift amount at each nozzle diameter D (in this case it becomes maximum at 17 D). In
addition, it was found that the sound pressure (OASPL) of the cluster nozzle is smaller than that of thesingle nozzle when comparing with the same dimensionless lift amount.

Fig.1 Result of subscale configuration of H3-30. (Acoustic field: static pressure,
Hydrodynamics of jet: temperature)

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.2 Interaction between cold cluster jet and launch pad (instantaneous field ofdensity and pressure).

Publications
N/A

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

OpenMP

Number of Processes

64 - 119

Elapsed Time per Case

1,440.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 5.03
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

41,901,509.38

5.49

SORA-PP

135,532.99

1.70

SORA-LM

880.090.45

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

5,591.15

3.87

/data

33,975.56

0.63

/ltmp

5,913.99

0.45

Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

111.514.80*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

JAXA Supercomputer System Annual Report April 2017-March 2018

DSMC analysis of the rarefied gas flows
Report Number：R17EG3214
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4446/
Responsible Representative
Eiji Shima, Resarch and Development Directorate, Resarch Unit III

Contact Information
Hideyo Negishi negishi.hideyo@jaxa.jp

Members
Hiroaki Amakawa, Takayuki Ito, Hideyo Negishi, Yoichi Ohnishi, Miki Nishimoto, Yu Daimon,
Ashvin Hosangadi, Masaaki Ino, Osamu Fukasawa, Shinji Ohno, Andrea Zambon,
Takenori Nakajima, YUKA Akimura, Takashi Amemiya, Hironori Fujiwara, Hiroumi Tani,
Takuya Iimura, Keiichiro Fujimoto, Tetsufumi Ohmaru, AKIKO Kotani, Taroh Fukuda,
Mayu Matsumoto, Masashi Toyama, Daiki Muto, Susumu Teramoto, Takahiko Toki

Abstract
To understand the rearfield gas flow phenomenon in high altitude and outer space, which is difficult to
conduct ground test, and to predict the aerodynamic / thermal environment for reentry and the thermalload of gas plume from a thruster, we aim to develop a practical tool that can deal with actual shape andshort analysis period.
http://www.kenkai.jaxa.jp/eng/research/software/software.html

Reasons for using of JSS2
In order to respond timely to project requirements, it is necessary to simulate complex geometries ofactual spacecraft and to analyze a large number of conditions in a short period.

Achievements of the YearWe evaluated the risk of abnormally high temperature due to the interaction between the thruster
plume and the loading of the HTV-X by using the rarefield gas flow analysis tool developed at Research
Unit III. It predicted the plume interaction and the heat load with the loading. We contributed tochanging the RCS thruster attachment position and angle. Figure 1 shows the simulation result of HTVX.

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.1 Plume simulation for HTV-X, number of density distribution

Publications
 URLs for the Research Results on the Web1) http://www.kenkai.jaxa.jp/eng/research/software/software.html

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

N/A

Number of Processes

300 - 625

Elapsed Time per Case

50.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.99
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

8,234,867.05

1.08

SORA-PP

1,337.81

0.02

SORA-LM

4.64

0.00

SORA-TPP

11.25

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

509.62

0.35

/data

25,306.17

0.47

/ltmp

16,404.39

1.24

Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

0.24

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

JAXA Supercomputer System Annual Report April 2017-March 2018

Numerical Simulation of Propellant Management for Rockets and Spacecrafts
Report Number：R17EG3215
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4447/
Responsible Representative
Yutaka Umemura, Researchand Development Directorate, Research Unit III

Contact Information
Yutaka UMEMURA umemura.yutaka@jaxa.jp

Members
Tetsuji Ogawa, Hideyo Negishi, Yoichi Ohnishi, Yu Daimon, Osamu Fukasawa,
Takuya Iimura, Keiichiro Fujimoto, Masashi Toyama, Akimitsu Terunuma

Abstract
In order to improve the payload capacity of spacecraft, it is necessary to optimally design the propellant
amount on board under the uncertainty of cryogenic propellant evaporation and low gravity environment.
This project has been conducting numerical simulation development for the cryogenic propellant
thermal flow analysis. By understanding the internal heat flow of the propellant tank and the feed line, it
is linked to the change of propellant system design and operation.

Reasons for using of JSS2
In the thermal flow analysis inside upper stage propellant tanks, the calculation lattice is as small as
several millimeters in order to consider a evaporation on the liquid surface, and it is necessary to solve
operation time of 500 seconds or more. The calculation load of this tank thermal flow analysis is so largethat it requires the supercomputer's performance.

Achievements of the YearThe flow in the upper propellant tank during flight operation is changing every moment due to thedifference in fluid density and rocket's acceleration.
From improving the evaluation of the heat transferred to the liquid surface by implementing a physicalmodel that takes into consideration the effects of evaporation and component mixing such as helium, theupper stage of the H-IIA rocket Simulation from engine start to inertial flight after engine stop was
realized.

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.1 The thermal flow behavior inside the upper stage propellant tankPublications
 Non peer-reviewed papers
1) Liquid Nitrogen Chill-down Process Prediction by Direct Interface Tracking Approach, Yutaka
UMEMURA, Takehiro HIMENO, Osamu KAWANAMI, Wataru SARAE, Kiyoshi KINEFUCHI,
Hiroaki KOBAYASHI, Osamu FUKASAWA, Propulsion & Energy 20172) Visualization for Liquid Behavior under Low Acceleration Attitude Control, Yutaka UMEMURA,
Takehiro HIMENO, Daichi HABA, Osamu FUKASAWA, Mayu MATSUMOTO, Yasuhiro SAITO
3) Study on Simulation Technology for Improving the Cryogenic Propellant Management in the SpaceTransfer Vehicle, Yutaka UMEMURA, Takehiro HIMENO, Daichi HABA, Osamu KAWANAMI,
Osamu FUKASAWAJAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

OpenMP

Number of Processes

3-4

Elapsed Time per Case

104.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.92
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

4,481,020.35

0.59

SORA-PP

537,755.45

6.73

SORA-LM

81.10

0.04

SORA-TPP

8,021.22

0.89

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

646.24

0.45

/data

22,964.06

0.42

/ltmp

15,688.24

1.18

Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

0.24

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

JAXA Supercomputer System Annual Report April 2017-March 2018

Development of Quantitative Safety Analysis Method by High-fidelity Simulations
Report Number：R17EG3216
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4448/
Responsible Representative
Eiji Shima, Reseach and Development Directorate, Reseach Unit III

Contact Information
Keiichiro Fujimoto fujimoto.keiichiro@jaxa.jp

Members
Keiichiro Fujimoto, Takayuki Itoh, Shota Suto, Tetsufumi Ohmaru, Akimitsu Terunuma

Abstract
In order to perform detailed destructive re-entry safety analysis and to obtain the validation data forthe empirical models, the aerodynamic and heat flux analysis under the wide range of flow conditions
based on the developed rapid turn-around CFD method is carried out. In addition, by using thedeveloped tools, the aerodynamic and heat flux design analysis are conducted in order to support the
research and development activities for the small re-entry capsule installed in HTV and the fly-back reusable rocket.

Reasons for using of JSS2
Accurate high-fidelity numerical simulations for the complicated physics under the wide range ofconditions is essential for the quantitative safety analysis. In addition, the analysis methods and its results
are high-level confidential information. Therefore, high-performance own supercomputer system isessential.

Achievements of the YearIn the conventional re-entry safety analysis, the aerodynamic and heat flux models with conservative
assumptions are used, and the system shape is treated as the combination of the simple geometries suchas the sphere and the cylinders. Due to these conservative assumptions, the predicted risk is generally
resulting in the conservative risk which includes the various margins. To meet the challenging safety
requirement in the near-future by the design for safety at the early design stages, an establishment of the
new destructive re-entry safety analysis method based on the high-fidelity numerical simulations isessential.

JAXA Supercomputer System Annual Report April 2017-March 2018

Therefore, in order to establish new re-entry safety analysis method, the detailed CFD analysis iscarried out to obtain surface heat-flux distributions for the comparison with that by empirical heat-flux
model employed for safety analysis. Computed heat flux distributions obtained by CFD is compared withthat by the empirical correlation model for simplified upper stage in Fig1.Results obtained by empiricalmodel are generally agreed well with that by CFD including small curvature area where larger heat flux
is observed. Research and development activities to realize next generation space transportation and reentry systems such as the small re-entry capsule installed in HTV and the re-usable fly-back booster are
under the way at JAXA.
In the aerodynamic design studies for such vehicles, large-scale parametric CFD analysis under thewide range of flow conditions is essential. Aerodynamic analysis is the most time-consuming process
which is the bottle-neck for the conceptual design and the probabilistic analysis. In this study, rapid turnaround time CFD tool (LS-FLOW) is employed for such parametric studies. For the development ofsmall re-entry capsule installed in HTV, the aeroacoustics CFD is carried out to predict the pressure
fluctuation level from the hypersonic through the subsonic conditions to decide the acoustics level forthe enviormental resistance tests (Fig 2), aerodynamic CFD for 6 degree-of-freedom trajectory analysis
is carried out to decide the side wind requirement for the high-altitude drop tests (Fig 3).
Parametric CFD studies for wide range of flow conditions are carried out for both studies. For the
aerodynamic design of the fly-back booster demonstrator, large scale parametric CFD study of various
configuration under the wide range of flow conditions is conducted. By the application of the developed
CFD tool, large scale parametric CFD analysis becomes available, which is the key for the success of thenext generation space transportation and the re-entry vehicles.

Fig.1 Comparison of surface heat-flux distributions obtained by CFD and theempirical model for rocket upper stageJAXA Supercomputer System Annual Report April 2017-March 2018

Fig.2 Aeroacoustics CFD for the small re-entry capsule installed in HTV

Fig.3 6 DoF trajectory analysis for drop test of the small re-entry capsule installed in HTVJAXA Supercomputer System Annual Report April 2017-March 2018

Publications
 Peer-reviewed papers
1) Ryuta Hatakenaka et al., "Thermal Design of Small Sample-Return Capsule Integrated into HTV,"ICES 2017, 2017.
 Non peer-reviewed papers
1) K. Fujimoto, H. Tani, H. Negishi, Y. Saito, N. Iizuka, and K. Okita, "High-fidelity Numerical
Simulations for Destructive Re-entry of Upper Stages," in 7th European Conference on Space
Debris, 2017.
2) F. Keiichiro, N. Hideyo, S. Yasuhiro, M. Spel, and G. Prigent, "BENCHMARK OF JAXA AND
CNES

RE-ENTRY

SAFETYANALYSIS

TOOLS

FOR

ACCURATE

HEAT-FLUXPREDICTION," in IAASS 2017, 2017.
3) F. Keiichiro, N. Hideyo, N. Ryoh, and N. Kazuyuki, "Aero-Acoustics CFD Prediction for Re-entry
Capsule at Subsonic to Supersonic Regine," in AIAA Scitech 2018, 2018.
4) F. Keiichiro, N. Hideyo, S. Yasuhiro, N. Iizuka, and K. Okita, "Aerodynamic Characteristics andHeat Flux Model Development for Reentry Safety Analysis of Rocket Upper Stages", 31st CFD
Symposium, E09-4, 2017.
 Other
1) F. Keiichiro et al., "Uncertainty Quantification for Destructive Re-Entry Risk Analysis", Stardust
Final Conference Advances in Asteroids and Space Debris Engineering and Science, Springer, 2018.

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

N/A

Number of Processes

64 - 512

Elapsed Time per Case

72.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.56
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

4,493,003.30

0.60

SORA-PP

0.00

0.00

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

421.40

0.29

/data

25,614.73

0.47

/ltmp

14,990.70

1.13Archiver Resources
Archiver System Name

Storage used(TiB)

Fraction of Usage*2 (%)

J-SPACE

0.24

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

JAXA Supercomputer System Annual Report April 2017-March 2018

Numerical analysis on high-temperature Hypersonic flow
Report Number：R17EG3217
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4449/
Responsible Representative
Koichi Okita, Research and Development directrate, Research unit IV

Contact Information
Hideyuki Tanno tanno.hideyuki@jaxa.jp

Members
Junpei Yamamoto

Abstract
Numerical simulation on high-temperature shock tunnel HIEST

Reasons for using of JSS2
Requirement for huge numerical simulation.

Achievements of the Year
Three component aerodynamic coeffcients of Hyflex lifting body model were obtained.

JAXA Supercomputer System Annual Report April 2017-March 2018

Fig.1 Pressure contour around Hyflex reentry vehicle (V=3km/s)

Publications
 Peer-reviewed papers
1) Master thesis, "Numerical analysis of hypersonic flow around lifting body vehicle model", Tohoku
Univ. 2018

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

Automatic Parallelizatio

Number of Processes

2 - 100

Elapsed Time per Case

100.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.11
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

880,584.26

0.12

SORA-PP

0.00

0.00

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

476.84

0.33

/data

9,765.63

0.18

/ltmp

1,953.13

0.15

Archiver Resources
Archiver System 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

JAXA Supercomputer System Annual Report April 2017-March 2018

Uncertainty quantification on satellite thermal design
Report Number：R17EG3288
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4450/
Responsible Representative
Eiji Shima, Research and Development Directorate, Research Unit

Contact Information
Hiroshi Kato kato.hiroshi@jaxa.jp

Members
Hiroshi Kato

Abstract
Our purpose is to improving the satellite thermal design process by developing a key technology of"satellite thermal environment uncertainty quantification".

Reasons for using of JSS2
There is no environment to perform the satellite thermal analyses of numerous samples under realistic
time.

Achievements of the YearWe developed an method to create emulator for satellite thermal simulator using the Gauss process
regression. The method was applied to actual satellite thermal problems, and the effectiveness was shown.
JSS 2 was employed to study the speedup of calculation of the Gaussian process regression.

Publications
 Peer-reviewed papers
1) Hiroshi Kato, Makiko Ando, and Yasuhiro Fukuzoe, "Toward Uncertainty Quantification in Satellite
Thermal Design," Transactions, 2017. (Accepted)
 Presentations
1) Hiroshi Kato, Makiko Ando, and Yasuhiro Fukuzoe, "Toward Uncertainty Quantification in Satellite
Thermal Design," 31st International Symposium on Space Technology and Science, June 9, 2017,
Matsuyama, Japan.

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

MPI

Thread Parallelization Methods

OpenMP

Number of Processes

64

Elapsed Time per Case

0.00 seconds

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.00
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

0.36

0.00

SORA-PP

0.00

0.00

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

011.92

0.01

/data

2,384.19

0.04

/ltmp

488.280.04

Archiver Resources
Archiver System 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

JAXA Supercomputer System Annual Report April 2017-March 2018

Fundamental Studies of Methane RCS
Report Number：R17EG3500
Subject Category：Research and Development
URL：https://www.jss.jaxa.jp/ar/e2017/4451/
Responsible Representative
Daiki Terakado, Research and Development Directorate, Research Unit IV

Contact Information
Daiki Terakado

terakado.daiki@jaxa.jp

Members
Daiki Terakado

Abstract
The present RCS of hydrazine used for controling rockets has a weak point on its toxicity. The present
project focuses on the non-toxic property of methane and develops safer RCS system for the future
rockets.

Reasons for using of JSS2
The present computation needs more than 10 species reactive computation, so that the computational
cost is very large. In addition, a massive parametric study will be conduted to find the optimal way of
injection. Thus, using supercomputer is necessary.

Achievements of the Year
N/A

Publications
N/A

JAXA Supercomputer System Annual Report April 2017-March 2018

Usage of JSS2
 Computational Information
Parallelization Methods

N/A

Thread Parallelization Methods

N/A

Number of Processes

1

Elapsed Time per Case

24.00 hours

 Resources Used
Fraction of Usage in Total Resources*1 (%): 0.00
Details
Computing Resources
System Name

Amount of Core Time (core x hours)

Fraction of Usage*2 (%)

SORA-MA

0.00

0.00

SORA-PP

26.64

0.00

SORA-LM

0.00

0.00

SORA-TPP

0.00

0.00

File System Resources
File System Name

Storage assigned(GiB)

Fraction of Usage*2 (%)/home

158.95

0.11

/data

3,255.21

0.06

/ltmp

651.040.05

Archiver Resources
Archiver System 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