Film-Boiling Heat Transfer

Abstract

Publisher Summary Heat exchange processes, accompanied by film boiling, are widespread in such fields of technology as metallurgy, during thermal treatment of metals; radioelectronics, in temperature control of electronic equipment, and power production. Processes of heat and mass transfer for film boiling in channels, especially, for turbulent flow arc extremely complicated. The studies performed permit an understanding of the main features of these processes. In some special cases, these studies provide experimental data and techniques needed for the quantitative calculations of heat transfer and hydraulic losses. A complex of experimental studies of the structure and mechanism of two-phase flows for film boiling in channels is needed in order to develop further theoretical studies. A mathematical model consisting of a system of one-dimensional equations for each of the phases seems to be the most promising one for calculating heat transfer and hydrodynamic losses for film boiling in channels. In order to obtain a complete mathematical model, it is necessary to find from the experimental data (and in some cases, analytically) relations for the coefficients included in the model. To obtain these relations for all the modes of film boiling in channels and for conditions of mode changeover is one of the main tasks of further studies. Further experimental studies depend for their success on the methods of measuring temperature fields, velocity fields, quality, and interface configurations.