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

aFJR light weight sound absorption liner technology development
Report Number: R18EA2180
Subject Category: Aeronautical Technology
URL: https://www.jss.jaxa.jp/en/ar/e2018/9074/
Responsible Representative
Toshio Nishizawa, Aeronautical Technology Directorate, Propulsion Research Unit
Contact Information
Shunji ENOMOTO (enomoto.shunji@jaxa.jp)
Members
Shunji Enomoto, Tatsuya Ishii (JAXA), Hitoshi Morita, Hidemi Toh (Kanazawa Institute of Technology)
Abstract
In order to improve the environmental compatibility of jet engines, we are developing sound absorbing liner
technology to reduce jet engine noise. By a simulation that sound waves are absorbed by the sound absorbing liner,
we aim to understand the characteristics of the sound absorbing liner and devise a shape with a higher soundabsorption coefficient.
Ref. URL: http://www.aero.jaxa.jp/eng/research/ecat/afjr/
Reasons for using JSS2
The calculation is LES with a large amount of computation and storage usage. It was necessary to use SORAPP, TPP, and SORA-FS.
Achievements of the YearWe attempted to acquire the sound absorbing characteristics of the sound absorbing liner under the glazing flow
assuming a two-dimensional laminar flow by using UPACS-LES which is an analytical code with less attenuationof sound waves using a 6th order compact scheme. In Fig. 1, a sound wave passes through the hole of the soundabsorbing liner. Figs. 2 and 3 are flow velocities (particle velocities) in and around the hole of the sound absorbingliner. Fig. 2 shows the case without glazing flow, the particle velocities reciprocate in the hole by the sound, andthe shear is strong at the corner part of the hole. Fig. 3 shows a case where a glazing flow is present. Steady vortex
is generated by the glazing flow, and the sound deforms the vortex. The mechanism of sound absorption differs
considerably as compared with the case without glazing flow.

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JAXA Special Publication JAXA-SP-19-003E

Fig. 1: Sound pressure of acoustic liner with glazing flow
(Video. Video is available on the web.)

Fig. 2: Particle velocity inside the hole of the acoustic liner without glazing flow
(Video. Video is available on the web.)－10－

This document is provided by JAXA.

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

Fig. 3: Particle velocity inside the hole of the acoustic liner with glazing flow
(Video. Video is available on the web.)

Publications- Non peer-reviewed papers
1) Shunji Enomoto, Tatsuya Ishii (JAXA), Yusuke Akamisaka, Hidemi Toh (Kanazawa Institute of Technology),“Numerical Analysis of Acoustic Liner Performance in an Impedance Tube Test”, Proceedings of the 50th Fluid
Dynamics Conference / the 36th Aerospace Numerical Simulation Symposium, JAXA-SP-18-005
2) Hitoshi Morita, Yusuke Akamisaka, Hidemi Toh (Kanazawa Institute of Technology), Shunji Enomoto,Tatsuya Ishii, Kenichiro Nagai (JAXA), “Effect on acoustic absorption properties of flow condition and acoustic
liner aperture ratio in the grazing flow”, The 59th conference on Aerospace Propulsion and Power, The Japan
Society for Aeronautical and Space Sciences.

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This document is provided by JAXA.

JAXA Special Publication JAXA-SP-19-003E

Usage of JSS2


Computational Information
Process Parallelization Methods

MPI

Thread Parallelization Methods

N/A

Number of Processes

24Elapsed Time per Case

40 Hour (s)Resources UsedFraction of Usage in Total Resources*1 (%): 0.09
Details
Computational Resources
System Name

Amount of Core Time(core x hours)

Fraction of Usage*2 (%)

SORA-MA

0.00

0.00

SORA-PP

51,971.67

0.42

SORA-LM

0.00

0.00

SORA-TPP

60,741.52

4.44

File System Resources
File System Name

Storage Assigned (GiB)

Fraction of Usage*2 (%)

/home

11.05

0.01

/data

3,329.19

0.06

/ltmp

665.84

0.06

Archiver Resources
Archiver Name

Storage Used (TiB)

J-SPACE

Fraction of Usage*2 (%)
9.53

0.33

*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.

－12－This document is provided by JAXA.