SOME CALCULATION FEATURES OF TRANSIENT BEHAVIOR OF THE REACTOR

To analyze the features of calculating the transient behavior of fast breeder reactors, both using the classical system of kinetic equations and using the system of partial neutron transfer equations, computational studies of the test model of the MET1000 reactor developed under the Generation-IV project were carried out. As transient processes, displacements (dumping) of control rods were simulated with the assessment of reactivity effects in the specified reactor through the solution of stationary problems, i. e. through the use of an asymptotic estimate of the reactivity obtained from solving stationary homogeneous neutron transfer equations and from processing by the Inverse Solution of the Kinetics Equation method of solving a transient problem. Test calculations were performed in the 26th and 28th group approximations using the ABBN-93 and ABBN-RF libraries and eight groups of delayed neutrons. It is shown that the features of the determination of both calculation and measurement of the effects of reactivity and efficiency of control rods in Fast Breeder Reactors are associated with the presence of both instantaneous and delayed neutrons in the reactor, with the working region of the neutron spectrum and with a change in the shape of the neutron flux in the process of introducing perturbation.