Investigation of film boiling at a liquid-liquid contact

In the present effort, film boiling of liquid nitrogen (LN2) on top of liquid water is numerically inves-tigated. Along with the volume of fluid based interface capturing method, the Hertz-Knudsen-Schrage based mass transfer model is used. Simulations have been performed on a two-dimensional domain, and the effects of single-mode and multimode disturbances on film boiling characteristics are studied. The film boiling characteristics and hydrodynamics involved are discussed and compared qualitatively with previous numerical studies of film boiling on a flat plate. The temperature and the velocity field of all three phases are obtained, and their temporal variation in the entire domain is presented. The evapora-tion rate of LN2 is found to increase with the increase of water temperature and increase in LN2 pool height. The water phase is disturbed throughout the film boiling, and the temperature and the velocity effects observed in the water phase are discussed. Simulations with low and high amplitude initial distur-bances are also performed. The evaporation rate for higher amplitude initial disturbances is observed to be more than the case with smaller amplitude initial disturbances. The numerically obtained results are validated by previously reported experimental studies, and some qualitative trends are compared with experiments performed in the present study. (C) 2022 Elsevier Ltd. All rights reserved.