Abstract In this paper, a combined photographic and thermal study of interfacial behaviour during boiling of liquid Nitrogen (LN2) over the water surface is reported. As a phenomenon, film boiling behavior is observed and the same is compared with the available correlations in literature. Apart from boiling, during experiments of LN2 drop over water of low temperature, icing has been observed which changes the overall interfacial activities. Rayleigh-Taylor instability (RTI) based criterion has been used to differentiate between regimes which are no bubbling, moderate and vigorous bubbling, based on the release of nitrogen vapor (N2) from the entrapped liquid layers. No bubbling behavior is observed when the equivalent diameter of the LN2 drop is lesser than the critical wavelength and the generated vapor flux during boiling is sufficient to levitate the drop. The N2 vapor cloud generated over the drop is also characterized by optical measurement to relate opacity and temperature. At the end, the phenomenon of sub-surface boiling is also reported through experiments of LN2 boiling over base fluids other than water.

中文翻译：

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了解液-液接触面中氮沸腾过程中的界面行为

摘要 本文报道了液氮 (LN2) 在水面上沸腾过程中界面行为的组合摄影和热学研究。作为一种现象，观察到薄膜沸腾行为，并将其与文献中可用的相关性进行比较。除了沸腾之外，在 LN2 滴在低温水中的实验中，还观察到结冰，这改变了整体界面活动。基于瑞利-泰勒不稳定性 (RTI) 的标准已被用于区分无鼓泡、中等和剧烈鼓泡的状态，基于氮蒸气 (N2) 从夹带的液体层中的释放。当 LN2 液滴的等效直径小于临界波长并且沸腾期间产生的蒸汽通量足以使液滴悬浮时，不会观察到起泡行为。在液滴上产生的 N2 蒸气云也可以通过光学测量来表征不透明度和温度。最后，还通过LN2在除水以外的基液上沸腾的实验报道了次表面沸腾现象。