Phase I: Review of EU-APR1400 PECS core catcher operation, relevant phenomena and methods for their analysis.
- Deion of the phenomena, available experimental data and analysis methodologies (including their validation and verification status) for:
o Jet breakup and fragmentation.
o Formation of debris particles.
o Liquid melt spreading under water after melt jet impingement on the pool bottom, including the effect of melt eruption.
o Debris agglomeration in case of incomplete solidification of the melt jet.
o Formation of porous particulate debris bed.
o Spreading of particulate debris in the pool by large scale flow structures.
o Spreading of particulate debris bed.
o Coolability of the debris bed.
- To provide the report on the results of above
Phase II: Preliminary assessment of the EU-APR1400 PECS performance in debris bed formation, spreading and coolability.
- Developing new models and using available methods for analysis of relevant phenomena (see deion of Phase I above) in order to asses EU-APR1400 PECS core catcher performance in debris bed formation, spreading and coolability.
- Preliminary analyses and calculation of the phenomena with the assumptions and reference scenario. The analysis shall include assessment of characteristics and uncertainties in particle bed formation when molten corium jet enters the near-saturated water pool in the cavity:
o Jet breakup and fragmentation.
o Formation of debris particles.
o Liquid melt spreading under water after melt jet impingement on the pool bottom.
o Debris agglomeration in case of incomplete solidification of the melt jet.
o Formation of porous particulate debris bed.
o Spreading of particulate debris in the pool by large scale flow structures.
o Spreading of particulate debris bed.
o Coolability of the debris bed.
o Bounding case analysis.
-Technical meeting with KHNP
- To deriver preliminary analysis report and calculation sheets based on the results of Task 2.1
Phase III: Continuation of the assessment of the EU-APR1400 PECS performance in coolability of corium debris.
- To carry out continuation of the necessary analyses and assessments of the EU-APR1400 PECS performance in coolability of corium debris (specific scope of the work to be decided based on the results of the Phase II).
- To deriver final report and calculation sheets based on the results of Task 3.1.
- Technical meeting with KHNP
