Study of subcooled film boiling on a horizontal disc: Part 2 - Experiments

Experiments were performed to study subcooled film boiling of performance liquid PF-5060 (made by 3-M Company) on a horizontal copper disc. The experiments were performed for two regimes of film boiling involving departing vapor bubbles (low subcooling) and nondeparting vapor bubbles (high subcooling). By employing high speed digital camera, data were obtained for temporal variation of bubble height, bubble shape and bubble growth rate over one cycle. Heat flux data were deduced from temperatures measured with thermocouples embedded in the solid. The results from the numerical model are compared with experimental data and are found to be in general agreement. Particle Tracking Velocimetry (PTV) experiments were performed for a configuration of non-departing vapor bubbles to study the flow field in the liquid phase. The PTV experiments point to the existence of natural convection flow in the liquid phase and is in qualitative agreement with the predictions available in the literature.