2017 Fiscal Year Final Research Report
Boinling Flow Dynamics in High-Temperature Large-Heat Capacity Tubes
Project/Area Number |
15K05845
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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 |
Research Field |
Thermal engineering
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Research Institution | Kansai University |
Principal Investigator |
Ozawa Mamoru 関西大学, 社会安全学部, 教授 (60112009)
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Project Period (FY) |
2015-04-01 – 2018-03-31
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Keywords | 重力注水 / リフラディング / 膜沸騰 / クエンチ / 逆環状流 / 遷移沸騰 / 集中定数系 / 並列管 |
Outline of Final Research Achievements |
The forced-feed and gravity-feed re-flooding experiments of a laboratory scale were conducted with a single and a parallel channel system, and phenomenological analysis was conducted. Boiling curves were estimated based on a rather simplified model, while sufficient for discussing dynamics during the quench. The estimated representative heat transfer coefficients in film and nucleate boiling process were nearly the same level of the conventional data presented in so-far published literatures. The cooling process of superheated high-temperature tubes is controlled mainly by the heat capacities of wall and water and the injected amount of water, and the formulated lumped-parameter model well represented the wall-temperature history during the re-flooding. In addition, in a parallel-channel system, flow oscillation between tubes, being so-called density wave oscillation, was observed. This oscillation deteriorates the cooling capability in film and transition boiling region.
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Free Research Field |
熱工学
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