2003 Fiscal Year Final Research Report Summary
Fabrication of Artificial Boiling Surface Using Micro Machining Technique -Clarification of Mechanism, Modeling and Control of Heat Transfer -
| Project/Area Number |
14350101
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Thermal engineering
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| Research Institution | The University of Tokyo |
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Principal Investigator |
MASAHIRO Shoji The University of Tokyo, Graduate School of Engineering, Professor, 大学院・工学系研究科, 教授 (00011130)
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| Co-Investigator(Kenkyū-buntansha) |
MATSUMOTO Sohei National Institute of Advanced Industrial Science and Technology, Senior Research Scientist, 機械システム研究部門, 主任研究員 (70358050)
INOUE Mitsuru The University of Tokyo, Graduate School of Engineering, Assistant, 大学院・工学系研究科, 助手 (30010854)
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| Project Period (FY) |
2002 – 2003
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| Keywords | Boiling / Nucleate boiling / Artificial cavity / Bubble dynamics / Nucleate site interaction |
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| Research Abstract |
With aims of making clear the heat transfer mechanism of pool nucleate boiling, the mechanism of nucleation site interaction, serial experiments of boiling using boiling surfaces with artificial cavities were performed. The analysis of data using nonlinear chaos dynamics was also made to clarify the complexity of the phenomena. In the experiment, the effects of cavity spacing, material and thermal capacity of the heated surface on the nucleation site interaction were extensively investigated by employing twin artificial cavities with cylindrical shape of 10 micron meters in diameter and 80 micron meters. As the results, it is found that the nucleation site interaction was governed by three effect factors of 1)thermal, 2)hydrodynamic and 3) bubble coalescence. When we pay attention to bubble departure frequency, the interaction was classified into four regimes affected by the three factors. To confirm the universality and generality of the results, the experiments using triple cavities and iso-propanol as a test liquid were performed.
To understand the mechanism and complexity of boiling, the experiments of bubble dynamics were made in parallel in the air-water iso-thermal system. Namely, the features of air bubble generation from the orifices in water were investigated experimentally, and the data was analyzed using nonlinear chaos dynamics. The peculiar bubbling phenomena with a scaling law was found, which is well explained theoretically.
The above results have been published in international academic journals and have been highly evaluated.
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Research Products
(16 results)
