This paper will describe modifications made to the FRAPCON-3 and FRAPTRAN fuel performance codes and models that impact reactivity initiated accident (RIA) analyses. The modified models include an upper bound empirical and best estimate release models for fast transients, and a revised fuel failure model that accounts for ductile and brittle failure. Because experimental data exists for discrete test conditions, the codes and models are used to interpolate and to some extent, to extrapolate these test conditions. An upper bound empirical model for release is used to establish new recommended release fractions for long-lived and short lived (radioactive) isotopes for RIA events in Regulatory Guide 1.183 . A best estimate release model is used in FRAPTRAN 1.4 based on grain boundary gas concentrations from FRAPCON-3.4 to predict release for RIA events. Code and model predictions will be compared to failure and release data from RIA tests to demonstrate accuracy.
Revised: January 20, 2012 |
Published: August 1, 2009
Citation
Beyer C.E., P.M. Clifford, K.J. Geelhood, and J.C. Voglewede. 2009.Regulatory Analysis of Reactivity Transients. In OECD/NEA Workshop on Nuclear Fuel Behaviour during Reactivity Initiated Accidents, September 9-11, 2009, Paris, France. Issy-Les-Moulineaux:Nuclear Energy Agency.PNNL-SA-66908.