Presentation of the results of exploratory containment iodine chemistry calculations for Phebus FPT-0 (Benchmark exercise and realistic calculations)
The results of the exploratory containment iodine chemistry calculations related to the first Phebus-FP test (benchmark exercise for explaining the reasons for code inconsistencies and realistic calculation for test preparation) are reported. The code benchmark results show that: (i) mechanistic codes (INSPECT and LIRIC) are in agreement for molecular iodine concentration in the gaseous phase, whereas empirical codes (IODE and IMPAIR) are in disagreement because they model differently HOI disproportionation and use different radiolytic constant values (iodide/iodate radiolysis); (ii) the molecular iodine concentrations in the gaseous phase are 10 to 100 times higher at acid pH (pH = 5) than at neutral pH (pH = 7); (iii) the presence of organic radicals in water does not change the concentrations of inorganic iodine species. The iodine mass distribution in the containment differs from one code to another, but all codes predict that the iodine concentration in the gaseous phase is high enough to be detected by the instrumentation expected to be used.
Bibliographic Reference: EUR 15701 EN (1994) 60 pp., FS, free of charge
Availability: Available from Joint Research Centre, Publication Department, I-21020 Ispra (Va.) (IT)
Record Number: 199410698 / Last updated on: 1995-03-21
Original language: en
Available languages: en