APPLICATION OF THE WIENER-HERMITE FUNCTIONAL METHOD TO A LINEAR FEEDBACK MODEL OF POINT REACTOR KINETICS DRIVEN BY RANDOM REACTIVITY NOISE

The Wiener-Hermite Functional (WHF) method is applied to a linear feed back model of point reactor kinetics in a second-order approximation. The neutron kinetics model is driven by Gaussian reactivity white nois e under stable reactor operating conditions. It contains explicitly on e group of delayed neutrons. In addition to the instantaneous negative power-reactivity feedback, the case of a positive feedback is include d with a Green's function which has the characteristics of a narrow-ba nd resonance filter. A first-order perturbation calculation is applied to solve approximately the system of non-linear integral equations re sulting in the frequency domain for the determination of the neutron s teady-state value and the power spectral density (PSD) of the neutrons . Under certain conditions the appearance of a (small) harmonic peak c an be observed in the PSD. (C) 1997 Elsevier Science Ltd.