著者

藤井 照重 太田 淳一 蒋 安衆 木島 和夫 金加 貴史

出版者

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.56, no.527, pp.p2093-2097, 1990-07

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In a system constructed by combining a gas turbine with a generator and an unfired waste-heat-recovery boiler,the exhausted gas becomes the heat input to the boiler and thus,the characteristics of this heat input obviously differ from those of the heat input to a conventional boiler system. To clarify the dynamic characteristics of the unfired waste-heat-recovery boiler,a simple naturalcirculation loop tube was manufactured to simulate an actual boiler. The experiments on dynamic responses with step changes in heat input were carried out for the cold start of about 10℃ and the warm start of 50℃ or 90℃. Dynamic responses such as the drum pressure,the drum water level and the natural-circulation velocity were clarified experimentally.

著者

竹島 敬志 藤井 照重 竹中 信幸 浅野 等

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.66, no.646, pp.1467-1472, 2000-06-25

被引用文献数

1

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An experimental study has been carried out to clarify the characteristics of the void fraction and liquid film thickness of air-water two-phase flow in vertical tubes of 25 mm inside diameter with wire coil of varying wire diameter and pitch. Flow pattern in the experiment of average void fraction and local void fractrion distribution in a cross section is bubble flow, and liquid film thickness is in the region of semi-annular and annular flow. It is clarified from these experiments that the average void fraction in tubes with a wire coil is lower than that of the smooth tube and decreases with the wire diameter owing to the centrifugal force of swirl flow which concentrates bubbles at the center of the tube, and the liquid film thickness between the wire coil is uniformed with the decrease of the pitch of wire coil and that liquid film becomes thicker after the passage of wire coil with the increase of the wire diameter.