JAXA Supercomputer System Annual Report April 2016-March 2017

Report Number: R16E0009

• Responsible Representative: Shigeru Hamamoto(Aeronautical Technology Directorate, Aerodynamics Research Unit)
• Contact Information: Hajime Miki(miki.hajime@jaxa.jp)
• Members: Hajime Miki, Kie Okabayashi, Yoshiki Takama, Keisuke Fujii
• Subject Category: Space(Space transportation)

Abstract

JAXA progresses research and development on lifting re-entry capsule as a return procedure for manned space activity. In atmospheric re-entry, gas jets emitted from reaction control system (RCS) interact with external flow around a capsule aero-thermodynamically. In order to predict its influence on capsule's aerodynamic and aerodynamic heating, RCS jet interaction is examined in various flow conditions by using not only wind tunnel testing but also CFD analysis.

Goal

Obtaining a prediction technique of RCS jet interaction for improving guidance control and thermal protection design of a lifting re-entry capsule

Objective

Discovering a parameter which correlates aerodynamic heating due to RCS jet interaction and main flow conditions by using both CFD analysis and wind tunnel testing

References and Links

N/A

Use of the Supercomputer

The supercomputer, JSS2, was used for CFD analysis of RCS jet interaction on a re-entry capsule.

Necessity of the Supercomputer

In order to improve a productivity of CFD data which cover wide condition of main flow and RCS jet, the use of JSS2 was necessary.

Achievements of the Year

CFD analysis using FaSTAR code was conducted against a model designed to simplify RCS jet interaction (Fig.1), and heating rate on the wall relative to free stream condition was examined. The results showed that the heating rate becomes larger as Reynolds number increase or as Mach number decrease. And it was found that a viscous interaction parameter correlates well with the change of aerodynamic heating due to free stream condition (Fig.2). Furthermore, the same trends appeared in the CFD analysis of re-entry capsule, and the effect of Reynold number matched with the results of wind tunnel testing qualitatively.

Fig.1:Aerodynamic heating caused by RCS jet interaction on a flat plate

Fig.2:Relationship between heating rate and viscous interaction parameter

Publications

N/A

Computational Information

• Parallelization Methods: Process Parallelization
• Process Parallelization Methods: MPI
• Thread Parallelization Methods: n/a
• Number of Processes: 128
• Number of Threads per Process: 1
• Number of Nodes Used: 4
• Elapsed Time per Case (Hours): 20
• Number of Cases: 50

Resources Used

Total Amount of Virtual Cost(Yen): 1,085,633

Breakdown List by Resources

Note: Virtual Cost=amount of cost, using the unit price list of JAXA Facility Utilization program(2016)

JAXA Supercomputer System Annual Report April 2016-March 2017