Frequency-Dependent Nodal Analysis of Boiling Water Reactor Stability

A general spatial kinetics model has been developed for boiling water reactor (BWR) stability analysis utilizing nodal analysis, a commonly used technique for analyzing power distributions in large power reactors. Kinetics parameters for use in the kinetics equations have been derived by utilizing self-consistent nodal data and power distribution. Spatial coupling effects on the stability margin have been analyzed for a typical BWR. Various influences on stability are investigated. Spatial kinetics is found to have substantial effects on the stability margins for density wave oscillations.