2021 Fiscal Year Final Research Report
Estimation of mixing ability by simultaneous hot-wire measurement of concentration and mass flux fluctuation and clarification of supersonic mixing transition
Project/Area Number |
19K04841
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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 |
Review Section |
Basic Section 24010:Aerospace engineering-related
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Research Institution | Osaka Prefecture University |
Principal Investigator |
Sakaue Shoji 大阪府立大学, 工学(系)研究科(研究院), 准教授 (70244655)
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Co-Investigator(Kenkyū-buntansha) |
新井 隆景 大阪府立大学, 工学(系)研究科(研究院), 客員教授 (10175945)
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Project Period (FY) |
2019-04-01 – 2022-03-31
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Keywords | 航空宇宙流体力学 / 超音速乱流 / 超音速混合遷移 / 熱線流速計 / 混合計測 |
Outline of Final Research Achievements |
The purpose of this study is to establish a simultaneous measurement of mass flux and concentration using hot-wire anemometer and to clarify the mechanism of mixing transition due to supersonic streamwise vortices. The hot-wire measurement requires the calibration using a flow of known concentration and mass flux. We have designed and constructed the supersonic calibration system, and confirmed its effectiveness in the measurement of air flow. Also, we have carried out the experiment and the numerical simulation of the flow field with streamwise vortices generated in supersonic wind tunnel. The results have clarified that the mixing transition of the supersonic streamwise vortices is achieved due to the hair-pin like vortex structures formed in its breakdown process and the Reynolds stress generated by the hair-pin vortex causing momentum exchange between freestream and vortex region.
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Free Research Field |
航空宇宙流体力学,乱流遷移,超音速乱流,流体計測法
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Academic Significance and Societal Importance of the Research Achievements |
本研究で開発した熱線回路は300kHz以上の応答周波数帯域を持ち,超音速ノズルを用いた校正システムを組み合わせることにより,超音速流中の高周波数変動を精度よく計測可能である.この熱線流速計による計測結果とPIVシステムによる計測結果を比較することで,本研究で使用したPIVシステムにより速度変動の空間分布が統計的に計測可能であることを確認した.さらに,この実験結果との比較により数値計算の精度と再現性を検証するとともに,混合遷移機構の詳細について知見を得た.
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