Comparison of neutronics calculations in a loss-of-flow accident

Results of a study of the accuracy of point kinetics reactivity predictions for loss-of-flow transients in a CRBR model are presented. Neutronics calculations were driven by realistic material and temperature histories representative of the thermal-hydraulic feedback which occurs in this type of transient. Reactivity solutions from 3 point kinetics variations and the quasistatic method are compared. One variation is found to be superior to the others for these transients; its prediction at power burst conditions is low by approximately $0.35. Accurate quasistatic neutronics calculations are found to have small CPU requirements relative to the time required for thermal-hydraulic calculations with SAS