Validation of the MELCOR 1.8.5 and SCDAP/RELAP5 codes and review of the MAAP models. Validation problem Quench-6

Validation analyses were performed within the scope of the validation matrix defined previously (see Report UJV--11658-T). This comprised the following steps: (i) Setting up a set of quantitative parameters to evaluate the codes; (ii) performing the validation analyses and their evaluation; (iii) assessment of severity of the differences identified and identification of the probable causes of the discrepancies; (iv) identification of realistic approaches to quality improvement of analyses as made possible by the existing code versions; and (v) proposal and initiation of activities aimed at additional improvement of the codes within the CSARP programme. The report deals with the validation problem Quench-6, whose aim it was to recalculate the problem defined for ISP-45 with the code distributed within the CSARP programme, i.e. SCDAP/RELAP5 Mod. 3.3. (P.A.)