Detailed Parametric Bifurcation Analysis of Advanced Heavy Water Reactor

摘要

The parametric bifurcation analysis of one node lumped parameter model for the Advanced Heavy Water Reactor (AHWR) is done in this work. The model available for BWR is adopted for the dynamical study of AHWR. This model includes point reactor kinetics equation for neutron balance in reactor core and one node parameter model is considered for fuel and coolant thermal hydraulics. The nonlinearity only due to reactivity is considered in the present model; nonlinearities due to heat transfer process between fuel-clad as well as fuel-coolant are neglected. The system loses its stability via Hopf bifurcation near the stability boundary as the system parameters are varied. The two types of the Hopf bifurcation have been observed here, supercritical Hopf bifurcation and subcritical Hopf bifurcation. The stability of the limit cycle can be detected by Floquet theory as well as by Lyapunov coefficient. The stability of observed limit cycles in this work has been analyzed by First Lyapunov coefficient. The stability maps have been plotted for different parameter combinations. In various parametric spaces, Hopf bifurcation points are observed and limit cycles (if they exist) of the solution for Hopf bifurcations are plotted. The oscillations in power level are shown for different initial conditions as well as wide range of parameter values. MATCONT code is used here for the study which is a bifurcation package tool for MATLAB.