JAXA Supercomputer System Annual Report April 2016-March 2017

Report Number: R16E0055

• Responsible Representative: Keiichi Kitamura(Yokohama National University)
• Contact Information: Ayano Inatomi(inatomi-ayano-ng@ynu.jp)
• Members: Ayano Inatomi, Takuya Aogaki, Keiichi Kitamura
• Subject Category: Space(Space transportation)

Abstract

In this study, we investigated details of flow field around the slender-bodied-vehicle numerically with configurations having different fineness ratios. Interestingly, the trend of 140 degrees of AOA is totally opposite to that observed at 50 degrees of AOA. It had been considered that the large nose bluntness and the small fineness ratio can reduce asymmetry and CY, however, this study showed that it is not true in the case over 90 degrees of AOA.

Goal

In order to search yaw force with reusable rocket in the condition of nose entry, we investigate how configurations impact on yaw force in back and forth 90 AOA.

Objective

We investigate details of flow field around the vehicle which have configurations numerically, and compere yaw force at more or less 90 degrees of angle of attack.

References and Links

N/A

Use of the Supercomputer

Because there are many cases with configurations and many grids, it is necessary to use super computer for getting accurate results in an efficient way.

Necessity of the Supercomputer

Because there are many cases with configurations and many grids, it is necessary to use super computer for getting accurate results in an efficient way.

Achievements of the Year

In this study, we investigated details of flow field around the slender-bodied-vehicle numerically. The configuration consisting of 'nose cone' and 'square aftbody' parts was employed as the baseline, and then, compared with other configurations having different fineness ratios. In the case of 50 degrees of AOA, according to our computed results, the longer the model became, the more asymmetry appeared (Fig. 1). CY and asymmetry were found to be attributed not only to the length of the body, but also to the nose bluntness. On the contrary, in the case of 140 degrees of AOA, the shorter the model became, the more asymmetry appeared (Fig. 2). Furthermore, the large nose bluntness increased CY. Interestingly, this trend is totally opposite to that observed at 50 degrees of AOA. It had been considered that the large nose bluntness and the small fineness ratio can reduce asymmetry and CY, however, this study showed that it is not true in the case over 90 degrees of AOA, due to complex wake flow structure discovered in the present numerical simulations.

Fig.1:AOA = 50 [degrees](Left:(b) Model A (baseline),Right:(d) Model B (half size model))

Fig.2:AOA = 140 [degrees](Left:(b) Model A (baseline),Rigth:(d) Model B (half size model))

Publications

Presentations

1) Inatomi, A., Kitamura, K., Nonaka, S., 'Numerical Analysis on Reusable Rocket Aerodynamics with Reduced-yaw-force Configurations', 31st ISTS, Matsuyama, Japan, Jun 3-9, 2017.

Computational Information

• Parallelization Methods: Process Parallelization
• Process Parallelization Methods: MPI
• Thread Parallelization Methods: n/a
• Number of Processes: maximum 1024
• Number of Threads per Process: 1
• Number of Nodes Used: maximum 32
• Elapsed Time per Case (Hours): 8
• Number of Cases: 80

Resources Used

Total Amount of Virtual Cost(Yen): 4,183,937

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