High-resolution method applied to premixing phase of steam explosion

This paper describes the improved version of the general two-dimensional, multiphase flow code ESE. The ESE code has been developed to model the mixing process and interaction of molten core debris with water. In case of a steam explosion, a trigger may produce locally enhanced heat transfer and pressurization and may evolve into a shock propagating through the coarse mixture. The propagation phase of the interaction is not modeled by the code; however, the ESE provides for initial condition evolution in time. The indication of the amount of well-mixed melt at the time of the trigger occurrence can be deduced based on the code's results. The objective of this work is to present the advantages of the high-resolution method applied to a particular set of partial differential equations and to incorporate these advantages into a code that was conceived using less traveled paths, namely, ensemble averaging and use of available data in probabilistic density functions describing momentum and energy cofluctuation tensors