ABSTRACT
This chapter reviews the published information on low-quality and subcooled film boiling. In particular, the review focuses on the heat transfer mechanism in the inverted annular and slug flow regimes, and the minimum film boiling temperature. The chapter discusses the literature on inverted annular and slug flow film boiling, particularly as it pertains to loss-of-coolant accident analysis. Slug flow film boiling is usually encountered at low flows and void fractions which are too high to maintain inverted annular film boiling but too low to maintain dispersed flow film boiling. Although the development will eventually lead to more accurate and universal methods of predicting post-dryout heat transfer, lack of experimental verification of the proposed interfacial equations limits the use of current post-dryout models. Due to the lack of water data, studies using cryogenic and refrigerant fluids and studies on pool boiling have been extensively employed to extract parametric trends and correlations.
