Fabrication of Artificial Boiling Surface Using Micro Machining Technique -Clarification of Mechanism, Modeling and Control of Heat Transfer -

利用微加工技术制造人工沸腾表面-传热机理、建模和控制的阐明-

基本信息

批准号：
14350101
负责人：
MASAHIRO Shoji
金额：
$ 9.6万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

项目摘要

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.

为了清除池成核沸腾的传热机理，成核位点相互作用的机制，使用了使用人工空腔的沸腾表面进行沸腾的沸腾实验。还进行了使用非线性混乱动力学的数据分析，以阐明现象的复杂性。在实验中，通过使用圆柱形形状的双直径为10微米和80微米米的圆柱形形状的双子人工腔，对腔间距，材料和热表面对成核位点相互作用的影响进行了广泛研究。结果，发现成核位点的相互作用受三个影响因素的控制，为1）热力学，2）流体动力和3）气泡结合。当我们注意气泡出发频率时，将相互作用归类为受三个因素影响的四个政权。为了确认结果的普遍性和普遍性，使用三腔和ISO丙醇作为测试液体进行了实验。要了解沸腾的机制和复杂性，气泡动力学的实验是在空气 - 水[水 - 热ISO热系统中并行进行的。也就是说，通过实验研究了水中气泡产生的特征，并使用非线性混乱动力学分析了数据。发现了具有缩放定律的特殊冒泡现象，理论上对此进行了很好的解释。上述结果已在国际学术期刊上发表，并得到了高度评价。