ABSTRACT
One of the most important potential severe accident sequences for any pressurized water reactor is a loss of coolant accident, or V-sequence, in one of the interfacing systems. This chapter addresses the retention and transport of fission products in the reactor coolant system (RCS) in V-sequence scenarios. The differences in cesium iodide retention in the various regions of the RCS are as great between the Modular Accident Analysis Program (MAAP) and Source Term Code Package (STCP) models as to indicate that considerable work is required to improve the understanding of the processes and bring the two methodologies into closer agreement. Discussion of fission product retention in the various regions of the RCS incorporates data from MAAP analyses, as well as a published Nuclear Regulatory Commission-sponsored analysis of a V-sequence that used the STCP.
