Measurements of critical heat flux and liquid–vapor structure near the heating surface in pool boiling of 2-propanol/water mixtures
Measurements of critical heat flux and liquid–vapor structure near the heating surface in pool boiling of 2-propanol/water mixtures
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DOI：
10.1016/j.ijheatmasstransfer.2009.11.028
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发表时间：
2010-03
影响因子：
5.2
通讯作者：
H. Sakashita;A. Ono;Yutaka Nakabayashi
中科院分区：
文献类型：
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作者：
H. Sakashita;A. Ono;Yutaka Nakabayashi
研究了大气压下 2-丙醇/水混合物在直径 12mm 的水平圆盘上的饱和池沸腾。在 2-丙醇浓度为 3.0–4.7mol% 时，混合物的 CHF 增加至水 CHF 的 1.7 倍。为了研究混合物中 CHF 增强的机制，使用电导探针测量了靠近加热表面的液-气结构。研究发现，在混合物沸腾过程中，液-汽结构在受热面径向上表现出强烈的不均匀性。受热面上方0.1~1mm处的空隙率在中心区域较小，在受热面周边附近较大。蒸汽团和加热表面之间的液体层比中心区域的水厚得多，并且在加热表面的外围附近变得更薄。这种较厚的液体层可能是 2-丙醇/水混合物中 CHF 增加的原因。
Saturated pool boiling of 2-propanol/water mixtures on a 12mm diameter horizontal disk under atmospheric pressure was investigated. The CHF of the mixtures increased up to 1.7 times the CHF of water at 3.0–4.7mol% concentrations of 2-propanol. To examine the mechanism of the CHF enhancement in the mixtures, liquid–vapor structures close to the heating surface were measured using a conductance probe. It was found that in the boiling of the mixtures, liquid–vapor structures show strong non-uniformity in the radial direction of the heating surface. The void fractions at 0.1–1mm above the heating surface are small at the central region and large near the periphery of the heating surface. The liquid layer between the vapor mass and the heating surface is considerably thicker than that of water at the central region and becomes thinner near the periphery of the heating surface. This thicker liquid layer is likely to be the cause of the CHF enhancement in the 2-propanol/water mixtures.