Abstract In the present study, spray cooling heat transfer characteristics were numerically investigated under the heat flux ranging from 50 to 170 W/cm2. Effect of nozzle height and spray pressure was also studied in order to reveal the microscopic mechanisms of the heat transfer enhancement from single-phase to nucleate boiling regions. A two-phase flow heat transfer model was adopted based on the Euler-Lagrangian approach. The dependence of thermo-physical properties of fluid on the temperature was also taken into account. The comparison between simulated wall temperature and experimental data demonstrates a satisfactory agreement. The results show that the heat transfer coefficient increases monotonously with the heat flux. In the nucleate boiling region, the wall film is thinner with a smaller velocity compared with those in the single-phase region. Spray cooling heat transfer is enhanced evidently as the nozzle height decreases and the spray pressure increases. The most important feature which separates the present study from the literature is that the numerical simulation in this paper presents some detailed microscopic characteristics, e.g. the wall film thickness and velocity, which play an important role in spray cooling heat transfer.

中文翻译：

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喷水冷却从单相到核沸腾区传热的数值研究

摘要 本研究对50~170 W/cm2热通量下的喷雾冷却传热特性进行了数值研究。还研究了喷嘴高度和喷雾压力的影响，以揭示从单相到核沸腾区域的传热增强的微观机制。采用基于欧拉-拉格朗日方法的两相流传热模型。还考虑了流体的热物理特性对温度的依赖性。模拟壁温与实验数据之间的比较表明了令人满意的一致性。结果表明，传热系数随着热通量的增加而单调增加。在核沸腾区，与单相区相比，壁膜更薄，速度更小。随着喷嘴高度的降低和喷雾压力的增加，喷雾冷却传热明显增强。将本研究与文献区分开来的最重要特征是本文中的数值模拟呈现了一些详细的微观特征，例如壁膜厚度和速度，它们在喷雾冷却传热中起着重要作用。