2015 Fiscal Year Final Research Report
Computational study on dynamics of anisotropic turbulence and development of turbulence modeling
| Project/Area Number |
25390149
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Multi-year Fund |
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| Section | 一般 |
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| Research Field |
Computational science
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| Research Institution | Nagoya University |
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Principal Investigator |
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| Co-Investigator(Kenkyū-buntansha) |
OKAMOTO Naoya 名古屋大学, 大学院工学研究科, 助教 (80547414)
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| Co-Investigator(Renkei-kenkyūsha) |
ISHIHARA Takashi 名古屋大学, 大学院工学研究科, 准教授 (10262495)
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| Project Period (FY) |
2013-04-01 – 2016-03-31
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| Keywords | 数理物理 / 乱流 / ウェーブレット |
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| Outline of Final Research Achievements |
We examined dynamics of three-dimensional (3D) homogeneous turbulence, in particular (1) error growth, (2) influence of small-scale vortices on turbulent statistics at large-scale statistics, and (3)decay of passive scalar turbulence, using direct numerical simulation (DNS). We find the following. (1) The large-scale statistics are not sensitive to the vortex structures and dynamics. (2) The error field exhibits self-similar growth so that its energy increases as k 4 t 6, where k is a wavenumber and t is time. The large-scale properties of the error play significant roles in the growth. (3) The large-scale invariant of a passive scalar is shown as the first DNS evidence. A turbulent model using orthogonal wavelets was developed for 3D turbulent channel flows bounded by two parallel planes. It is found that coherent vorticity, reconstructed from few intense vorticity wavelet coefficients, well preserves the statistical predictability and vortices of the turbulent flows.
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| Free Research Field |
計算科学
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