High Resolution Analysis of Unsteady Aerodynamics for RLG with Fast Fluid Solver FaSTAR
JAXA Supercomputer System Annual Report April 2016-March 2017
Report Number: R16E0103
- Responsible Representative: Yuichi Matsuo(Aeronautical Technology Directorate, Numerical Simulation Research Unit)
- Contact Information: Keiichi Murakami(murakei@chofu.jaxa.jp)
- Members: Yuki Matsui
- Subject Category: Basic Research(CFD)
Abstract
In order to obtain a low computation cost and stable high resolution solution for the aircraft Rudimentary Landing Gear (RLG), the CFD solver FaSTAR developed by JAXA is used as the central difference base, and in the place where the calculation is unstable, the numerical viscosity of the upwind difference To extend. As a result, the resolution in the high frequency region was improved.
Goal
Aim for the construction of numerical simulation method which can perform aerodynamic analysis with high resolution by using the unstructured CFD code ‘FaSTAR’ (developed by JAXA).
Objective
Suppress decay of physical quantity fluctuation due to numerical viscosity in high frequency region, obtain high resolution and stable solution
References and Links
N/A
Use of the Supercomputer
Computation analysis of unsteady aerodynamics
Necessity of the Supercomputer
Since unsteady aerodynamic analysis requires a huge amount of time for calculation, a high-speed computing environment is required.
Achievements of the Year
In order to obtain a low computation cost and stable high resolution solution for the aircraft Rudimentary Landing Gear (RLG).The non-viscous flux calculation is set to the second order central difference base, only the place where the calculation becomes unstable by the central difference is detected, the hybrid scheme which stabilizes the calculation is added by adding the numerical viscosity of the second order upwind difference, We introduced the development CFD solver FaSTAR developed by JAXA and conducted unsteady aerodynamic analysis. As a result, as shown in Fig.1, when visualizing the vortex of Hybrid scheme and Roe scheme constructed this time on the isosurface of Q value, the Hybrid scheme is more finely resolved than the Roe scheme. The pressure spectrum of the object surface is confirmed in Fig. 2, indicating that the Hybrid schemesuppresses the decay of SPL in the high frequency range.
From this, it is found that the non-viscous flux calculation is a form in which the numerical viscosity of the Roe scheme is added to the second order central difference base, and by increasing the numerical viscosity of the Roe scheme only in the point where the calculation is unstable, By using the controlled hybrid scheme, we obtained the knowledge that attenuation of fluctuation of the physical quantity in the high frequency region due to numerical viscosity issuppressed, and high resolution and stable solution can be obtained.
Publications
N/A
Computational Information
- Parallelization Methods: Process Parallelization
- Process Parallelization Methods: MPI
- Thread Parallelization Methods: n/a
- Number of Processes: 1024
- Number of Threads per Process: 1
- Number of Nodes Used: 1
- Elapsed Time per Case (Hours): 300
- Number of Cases: 6
Resources Used
Total Amount of Virtual Cost(Yen): 1,655,811
Breakdown List by Resources
System Name | Amount of Core Time(core x hours) | Virtual Cost(Yen) |
---|---|---|
SORA-MA | 334,965.82 | 541,309 |
SORA-PP | 19,953.45 | 170,362 |
SORA-LM | 1.02 | 23 |
SORA-TPP | 0.00 | 0 |
File System Name | Storage assigned(GiB) | Virtual Cost(Yen) |
---|---|---|
/home | 476.84 | 4,498 |
/data | 97,656.29 | 921,194 |
/ltmp | 1,953.13 | 18,423 |
Archiving System Name | Storage used(TiB) | Virtual Cost(Yen) |
---|---|---|
J-SPACE | 0.00 | 0 |
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