基于微液层模型的单汽泡生长数值模拟研究

核态沸腾换热在传热传质方面有着重要的作用，其发生机理和传热传质过程仍是研究的重点。随着实验手段的提高，微液层模型得到了广泛的关注。通过对微液层中传热传质的分析，建立了微液层厚度与热流密度和气化率之间的关系。利用界面扩散法对汽液相界面进行追踪，并在汽泡与加热壁面之间构建微液层模型，研究在核态沸腾条件下，微液层的变化对汽泡生长和加热壁面温度分布的影响。结果表明，数值模拟得到的汽泡生长过程和加热壁面温度分布与实验结果吻合得很好，初步验证了模型的正确性。并通过数值模拟，进一步分析了汽泡生长过程中微液层、干性区域和汽泡底部半径的变化规律以及壁面温度的分布情况。

Numerical Simulation of Single Bubble Evolution Based on Microlayer Model

Nucleate boiling heat transfer plays an important role in the heat and mass transfer. The mechanism and the heat and mass transfer of nucleate boiling are still the focus of the study. With the improvement of experimental methods, the microlayer model was confirmed and received extensive attention. The diffusion interface method was used to track the phase interface. Through the research on the heat and mass transfer in microlayer, the correlation of the microlayer thickness with the heat flux and gasification rate was established. The partial differential equation of the microlayer model was introduced at the bottom of the bubble. The effect of the change of the microlayer on the bubble evolution and the temperature distribution of the heating wall was studied in the condition of nucleate boiling. The results show that the bubble evolution process and the heating wall temperature distribution are in good agreement with those of the experiment, which indicates the accuracy of the model. Furthermore, the variation law of the microlayer, the dry zone and the bottom radius of the bubble and the heating wall temperature distribution were analyzed.