R-113池沸腾气泡行为的可视化及传热机理

利用ITO透明加热膜和高速摄影仪，对制冷工质R-113在压力为0.1 MPa的池沸腾的气泡行为进行了可视化研究.利用高速摄影仪观察得到了不同热通量下气泡的生长、脱离以及相邻气泡之间的合并情况.实验结果表明，随着热通量的升高，气泡的脱离时间减小，而加热壁面的汽化核心密度增大.文中给出了气泡的脱离时间、脱离直径以及汽化核心密度随热通量的变化曲线.在实验过程中，并没有观察到气泡底部的微液层在蒸干过程中有液体补充.最后，利用动态微液层模型对R-113的池沸腾换热曲线进行了预测，并将预测结果和实验结果进行了对比，结果显示，预测结果与实验结果符合较好.

Bubble dynamics and heat transfer mechanism of pool boiling of R-113

An experimental study was performed to observe bu bble behaviors and heat transfer mechanism of pool boiling of refrigerant R-113 at pressure 0.1 MPa.A transparent heater was used to observe bubble behavior o n the entire heater surface with a high-speed camera placed beneath the heater surface.The departure diameter, departure time of bubbles and nucleation density at different heat fluxes were obtained. As a bubble grew up, the dryout area of microlayer under the bubble could be obs erved.It was also observed that there was no liquid recruit into the microlayer in the experiment.Even at a very high heat flux, vapor stem could not be observe d, and the periodic generation and growth of primary vapor bubble is dominant. The relationship between nucleation density and heat flux was given.Based on the experimental results, boiling curve for R-113 was predicted by using the dynam ic microlayer model.As a result, the agreement between the predictive result bas ed on the dynamic microlayer model and the experiment data for boiling curve of R-113 is excellent.