2017 Fiscal Year Final Research Report
Energy transfer in anisotropic hydrodynamic turbulence
| Project/Area Number |
15K17971
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| Research Category |
Grant-in-Aid for Young Scientists (B)
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| Allocation Type | Multi-year Fund |
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| Research Field |
Fluid engineering
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| Research Institution | Kyoto University |
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Principal Investigator |
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| Research Collaborator |
TAKAOKA Masanori
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| Project Period (FY) |
2015-04-01 – 2018-03-31
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| Keywords | 流体乱流 / 異方性 / 乱流の共存 / ヒステリシス / エネルギー輸送 |
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| Outline of Final Research Achievements |
When the angular velocity of the system in rotating turbulence is varied, the transitions between quasi-two-dimensional anisotropic flow and isotropic three-dimensional flow occurs at different angular velocities. Namely, the transition shows a hysteresis. The quasi-two-dimensional anisotropic flow consists of inertial-wave turbulence, three-dimensional eddy turbulence, and large-scale columnar vortex. In stratified turbulence, anisotropy, dominance of internal waves, and validity of weak turbulence are evaluated from viewpoint of the linear time scale of internal waves and the nonlinear time scales of eddies. It was found that viscous dissipation at small wave numbers is not small in both rotating turbulence and stratified turbulence. This suggests that the viscous dissipation plays an important role in mechanism of formation and maintenance of coexist of different kinds of turbulence.
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| Free Research Field |
流体物理学
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