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- 2015
纳米流体沸腾模型中某些物理参数的理论探讨
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Abstract:
纳米流体核态沸腾理论预测模型的缺乏阻碍了其作为高效换热介质在工业系统中的应用。为实现对纳米流体核态沸腾的准确预测和计算, 该文在现有实验基础上对纳米流体核态沸腾的特有现象进行了机理分析, 建立了一系列的封闭方程来修正和完善经典的壁面热通量拆分模型, 将模拟结果与纳米流体及纯工质核态沸腾的实验数据进行了对比, 对模型中的一些物理参数进行了理论探讨。研究表明: 采用壁面热通量拆分模型模拟纳米流体核态沸腾的关键在于准确模拟纳米包覆层对汽泡成核、生长及脱离规律的影响, 特别是要准确把握壁面润湿性及壁面形态变化对核态沸腾特征的影响。
Abstract：The lack of accurate boiling heat transfer models for nanofluids limits their applications in industrial systems. This study describes the mechanisms for nucleate pool boiling of nanofluids based on experimental results in the literature. New closure correlations are given for the nucleate boiling parameters to improve the classical heat flux partitioning model. The numerical results agree well with available experimental data. The most important task when modeling nucleate boiling of nanofluids is to accurately predict the effects of the surface wettability and surface morphology caused by the nano-coating on the bubble nucleation, growth and departure from the heater surface.
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