抄録
We added models for the particle size distribution and non-local radiation heat transfer into a fuel-coolant interaction (FCI) simulation code JASMINE that was developed at Japan Atomic Energy Agency (JAEA) to extend the applicability of the code for ex-vessel melt coolability assessment. Also, modifications were made in the models related to melt particle generation and re-agglomeration of settled melt particles. The modified code was tested by simulating melt jet breakup experiments, namely selected cases of ALPHA/GPM series with alumina-zirconia mixture and steel melt by JAEA, and FARO experiments with urania-zirconia mixture by Joint Research Center (JRC) Ispra. Simulation results showed that the code reproduces the experimental results well for the cases with a deep subcooled water pool where the melt breaks up completely. On the other hand, significant underestimation of heat removal from the melt and overestimation of agglomeration of settled melt was encountered for conditions with the water pool at saturation temperature. The melt agglomeration behavior in the simulation was sensitive to model parameters on the agglomeration criterion and heat transfer depending on conditions.
