| Summary: | 碩士 === 國立交通大學 === 機械工程系 === 88 === The performance of nucleate pool boiling of dielectric liquid FC-87 on horizontal wires were investigated in this study. In order to understand the pool boiling heat transfer characteristics for high wetting low surface tension dielectric liquid, the liquid were boiled using 0.1-, 0.2- and 0.3-mm-diameter wires made of tungsten and molybdenum. The experimental results show that boiling heat transfer coefficients decreased withincreasing wire size. Compared tungsten and molybdenum of the same diameter, tungsten has higher heat transfer coefficients. The data showed incipience superheat of 17.8~32.2℃ and temperature excursion of 5~14℃. CHF occurs at heat flux between 1.7 105W/m2 and 2.35 105W/m2 ,and the smaller diameter wire has higher CHF .The Rohsenow correlation corrected by Danielson can predict experimental data of nucleate boiling heat transfer coefficients within 30% band of uncertainty. We can use You correlation to predict CHF , and prediction values are higher than experimental data.
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