2018 Fiscal Year Final Research Report
development of numerical analysis for monitoring transition process of vortices and prediction of vortex generation
Project/Area Number |
16K06094
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Fluid engineering
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Research Institution | Aichi Institute of Technology |
Principal Investigator |
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Project Period (FY) |
2016-04-01 – 2019-03-31
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Keywords | 渦発生 / 渦遷移 / swirlity / 予測旋回平面 / 渦発生キーフロー |
Outline of Final Research Achievements |
A numerical analysis technique has been developed to monitor the transition process of a vortex and its prediction in terms of the local topology, applying a topological physical quantity swirlity that specifies the unidirectionality and intensity of azimuthal flow. The swirlity specifies the process of vortex generation and then the swirl plane after the vortex generation can be predicted. The key flow as a trigger of the generation of a vortical flow is identified which direction is associated to the predicted swirl plane. In the flow decomposition of the subjected turbulent flow, the flow scale that composes the key flow can also be identified. In the analysis of the prediction of vortex generation using the swirlity, the feature of transition of predicted key flow may be applied to predict the generation at a specific time.
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Free Research Field |
流体力学
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Academic Significance and Societal Importance of the Research Achievements |
渦の発生は、宇宙、気象、海洋における渦だけでなく、航空機、発電プラント、構造物まで多様な工学に関わる。渦の統一的な定義は未確立であるが、主要な渦定義や渦の同定に用いられる定義は、速度勾配テンソルより導かれるローカルトポロジーに基づく定義である。本研究は、このローカルトポロジーにおける渦の遷移メカニズム、渦発生のキーフローの同定、swirlityやキーフローを用いた渦発生予測の評価、更にキーフロー生成の流れのスケールの同定を行う数値解析技術を構築した。本研究は、前述した様々なスケールの乱流渦現象や工学分野の流れにおいて適用が可能である。
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