ABSTRACT
Fission product transport processes in the primary coolant system (PCS) of a PWR depend on the prevai1ing flow and temperature fields. In turn, the self-heating fission products on deposition and revaporization, may affect the prevailing flow and temperature distributions. Thus, thermal hydraulic and fission product transport processes are coupled and should be so modeled.
Simultaneous treatment of the fission product transport, thermal hydraulics, and material transport processes has been modeled in the EPRI-sponsored SIAM code, which couples the codes CORMLT, PSAAC, and RAFT which, respectively, treat core degradation, PCS thermal hydraulics, and PCS aerosol transport. Calculation proceeds in a coupled manner at each time step, simultaneously in these three codes. The time dependent fission product release to the containment is calculated. Validation of parts of the SIAM code has been performed by comparison to measured aerosol transport data.
