著者

末永 陽介 柳岡 英樹 菊池 護 佐々木 駿

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.852, pp.17-00160-17-00160, 2017 (Released:2017-08-25)

参考文献数

19

被引用文献数

1

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Experimental study was performed to reveal the response characteristics of a stretched cylindrical diffusion flame to sinusoidal oscillation of air flow velocity. The cylindrical flame used in this study has a convex curvature with respect to air stream and is formed in air stream. The fuel is methane, diluted with nitrogen, and the oxidizer is air. Oscillation frequency f is varied from 5 Hz to 250 Hz. Velocity at the outlet of air supplying nozzle was changed sinusoidally with four speakers. Velocity at the fuel nozzle outlet was kept constant. The air velocity at the nozzle outlet is measured using particle image velocimetry. Flame radius rf, flame thickness δ, and flame luminosity Lf are obtained by using high speed video camera. Results are summarized as follows: Though fluctuation amplitude of the velocity gradient of air stream Δga is constant with increasing f, that of the fuel stream Δgf increases. The fluctuation amplitude of rf varies to quasi-steady at low frequency, while the fluctuation amplitude is reduced with increasing f. Lf does not respond to quasi-steady at low frequency. The fluctuation amplitude of Lf has maximum value at 50 Hz and is larger than that for the steady flame corresponding to the velocity fluctuation. It is considered that this complex change of the flame luminosity with respect to f is related to δ/rf which is associated with the flame curvature effect, ga which affects the flame stretch effect, and gf which impacts fuel transport.

著者

吉本 則之 渡辺 剛 小金澤 智之 菊池 護 廣沢 一郎

出版者

公益社団法人 日本表面科学会

雑誌

表面科学 (ISSN:03885321)

巻号頁・発行日

vol.35, no.4, pp.190-195, 2014-04-10 (Released:2014-04-22)

参考文献数

14

被引用文献数

1

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Two-dimensional grazing incidence X-ray diffraction (2D-GIXD) is one of the powerful methods to analyze crystal growth and structure of organic thin films. In this report, we show some experimental examples of 2D-GIXD measurements on organic semiconductor thin-films performed at SPring-8. First, polymorphic transformation of pentacene depending on film thickness observed by means of in-situ real-time 2D-GIXD is shown. Secondly, real-time observation of change in structure during thin-film growth of oligothiophenes by means of 2D-GIXD is shown. Finally, a result of crystal structure analysis from 2D-GIXD data of polycrystalline an oligothiophene thin film is reported.