VAPOR-FILM-UNIT MODEL AND HEAT-TRANSFER CORRELATION FOR NATURAL-CONVECTION FILM BOILING WITH WAVE MOTION UNDER SUBCOOLED CONDITIONS

This report presents a heat transfer model and correlation of natural- convection film-boiling heat transfer with interfacial wave motion und er subcooled conditions. First, the vapor-film-unit model developed fo r saturated film boiling in our previous report was extended to subcoo led film boiling along inclined and vertical flat-plates and also arou nd horizontal cylinders of large diameter. Next, based on the vapor-fi lm-unit model, a general form of heat transfer correlation of film boi ling with wave motion was developed. Comparison with experimental data showed that the present heat transfer model and correlation can predi ct the effects of the fluid properties, liquid subcooling, wall superh eat, the geometry and the size of the heat transfer surface on film-bo iling heat transfer with wave motion.