2024-03-29T12:32:35Z
https://kitami-it.repo.nii.ac.jp/oai
oai:kitami-it.repo.nii.ac.jp:00006810
2022-12-13T02:20:07Z
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ノズル内の二次元物体によってパッシブ制御された二次元噴流の組織構造
Coherent Structure in a Two-Dimensional Jet Passively Controled by Wake of a Cylinder Installed in Nozzle Contraction
Coherent Structure in a Two-Dimensional Jet Passively Controled by Wake of a Cylinder Installed in Nozzle Contraction
宮越, 勝美
羽二生, 博之
open access
社団法人日本機械学会, 宮越勝美,羽二生博之, 日本機械学会論文集B編, 69(678), 2003, 338-345.
It is possible to control the spread of a plane jet passively by the vortices from a two-dimensional cylinder installed in the nozzle contraction. In this study, the wake characteristics of a cylinder and the coherent structure of a jet by this passive control method were examined by flow visualization and quantitative velocity measurements. In wide range of strouhal number based on vortex shedding frequency and jet exit velocity, the spreads of the jet were found to be suppressed. This suppression is caused by the high frequency vortices from the control cylinder which inhibits growth and pairing of the low frequency vortices. On the other hand, in certain cases of the strouhal number being 0.05-0.10, the spread of the jet was remarkably enhanced associated with distinctive peaks of spectrum at higher order of vortex shedding frequency caused by the deformation of the vortices in flow contraction nozzle. In the case of enhanced mode, vortex from the cylinder moves to the opposite side shear layer with the same vorticity sign as the vortex, and it enhances roll up fo the shear layer.
application/pdf
日本機械学会
2003-02
jpn
journal article
VoR
https://kitami-it.repo.nii.ac.jp/records/6810
日本機械学会論文集B編
69
678
338
345
https://kitami-it.repo.nii.ac.jp/record/6810/files/4985.pdf
application/pdf
4.2 MB
2016-11-22