Development of fuel-coolant interaction analysis code

JASMINE-pre is a thermohydraulics simulation code specifically developed for the prediction of pre-mixing process in FCIs. It consists of a newly developed melt model and a two-phase flow model ACE3D. The melt model has three components, jet, pool and particles. The jet and pool are modeled one-dimensionally in the vertical and radial direction, respectively, while the particles are modeled with Lagrangian grouped-particle concept. Molten jet breakup in non-boiling and boiling conditions were simulated to test the basic capability of JASMINE-pre code. The calculation results showed that the code can simulate the molten jet breakup and multiphase mixing with and without steam generation. (author)