Study of Active Nucleation Site Density in Subcooled Nucleate Pool Boiling
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摘要: 为研究在过冷沸腾条件下的加热表面的活化核心密度尺度分布是否具有分形特征,运用核态沸腾换热机理模型对不同过冷度下的4种不锈钢换热表面的活化核心密度进行了预测.结果表明:对于特定的沸腾表面,过冷度不影响活化核心密度曲线的形式,预测曲线与作者提出的加热表面活化核心密度的分形描述相一致,从而进一步证明了该结论具有普遍性.Abstract: The active nucleation site density is an important parameter of nucleate boiling heat transfer model, but none of those theoretical models made by far has successfully predicted the active site density. A fractal model has recently been proposed by authors to describe the active site density in nucleate boiling. In order to study if the fractal model can be used in subcooled nucleate boiling, the active nucleation site densities of four stainless steel surfaces are predicted using the heat transfer model proposed by Judd and Hwang according to the nucleate boiling experiment data on different subcoolings. The predicted result indicates that the active nucleation site density curve is not affected by subcooling and agrees well with the fractal model by authors. The universality of the model is ulteriorly confirmed.
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Key words:
- superooling /
- boiling /
- heat transfer /
- active nucleation site /
- fractal
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