2 0 0 0 音波により励起される噴流の研究
- 著者
- 小川 信夫 牧 博司 黒田 健嗣
- 出版者
- 一般社団法人日本機械学会
- 雑誌
- 日本機械学會論文集. B編 (ISSN:03875016)
- 巻号頁・発行日
- vol.59, no.566, pp.2975-2981, 1993-10-25
- 被引用文献数
- 1
Control of turbulent jets has applications in the manufacturing industry. It has been reported that it is possible to control the jet structure by a pure tone. However, in pure-tone-excited jets, the detailed characteristics of the flow fields are unknown. In this paper, a jet excited by a pure tone radiated from the direction perpendicular to the axis is addressed. A woofer was set downstream near the nozzle. As a result, we found that the cross section of the jet was distorted elliptically in shape. It was clarified that the distorted cross section depended on frequency and sound pressure level of the excitation. This phenomenon is very useful to control jet flows, since it can change the characteristics of the flows. We attempted to clarify the mechanism of elliptical distortion of the jet cross section, assuming the mixing region of the jet was organized into many vortex rings in a time-averaged domain.
1 0 0 0 対向衝突乱流噴流の研究 (噴流中心の乱れと衝突面位置)
- 著者
- 小川 信夫 牧 博司 土方 邦夫
- 出版者
- 一般社団法人 日本機械学会
- 雑誌
- 日本機械学会論文集B編 (ISSN:03875016)
- 巻号頁・発行日
- vol.57, no.535, pp.935-942, 1991
From our previous reports, it is clarified that the fluctuations in the jet center have an important effect on opposed turbulent jet flow fields. In the jet center, where symmetrical flow fields are characterized, the turbulent structure will be different from those in other parts of the jet. In the turbulent opposed jet center, the fluctuating velocity plays role equal in importance to that of the mean velocity. The momentum which locates the impinging surface comprises three parts: that is, a mean velocity, a static pressure and a fluctuating velocity. The present paper deals with the influences of the variations of the fluctuating velocity, employing the turbulent lattice in the center of turbulent opposed jets, to the locations of the impinging surface.