2-PHASE FLOW IN POROUS-MEDIA WITH PHASE-CHANGE - POST DRYOUT HEAT-TRANSFER AND STEAM INJECTION

Two-phase flow processes thought to be important to in-core severe acc ident progression are reviewed. Two-dimensional dryout processes are t reated and the conclusion is reached that one-dimensional dryout limit s are adequate for predicting the onset of core melting. Post-dryout c onsiderations are used to justify study of heat transfer at a steam-wa ter interface. Steam injection into cold flowing water in a porous med ia is used to generate the steam-water interface. It is shown that all important characteristics of the interface can be predicted well enou gh for engineering purposes.