FP distribution analysis results by severe accident analysis code

The FP distributions inside the RPV, PCV, and R/B were evaluated using MAAP and SAMPSON codes. Table 1. shows the analysis results of distribution of Cs and Sr, which are the representative FP nuclide. The large uncertainties in the analysis results of both codes are caused by variations of FP models and chemical form of FP nuclide considering evaluation model.

Table 1縲FP (Cs and Sr) Distribution analysis results (deposition amount at the time of 6 days after the accident) (unit: kg)
Area Unit 1 Unit 2 Unit 3
Cs Sr Cs Sr Cs Sr
Inside the RPV 10ス90 0.4ス0.7 20ス150 13ス33 38ス110 11ス46
Inner wall of D/W 6ス29 0.2ス0.3 Approx. 0.9 0.2ス0.4 less than 0.1- 1 less than 0.1
S/P underwater 26ス74 0.4ス2 27ス130 3ス4 57ス140 1ス6
Release to environment less than 0.1-4 less than 0.1 less than 0.1-6 less than 0.1-0.4 less than 0.1-4 less than 0.1

シサReferenceシ IRID Completion report for "Improvement of recognition regarding the internal PCV condition of the reactor vessels using severe accident progression analysis and actual plant data" シス