Kinetics of Periodic Cascade Boosters from the Standpoint of Their Speed of Operation and Safety

A system of equations is formulated governing the kinetics of a reactor that is adequate for the purpose of describing transient neutron phenomena in a periodic cascade booster and includes all groups of delayed neutrons. An analytical solution of these equations for the case of constant neutron multiplication coefficient keff (booster with no reactivity modulation) is used. The calculations show that periodic cascade boosters have substantial advantages over single-section boosters. The main advantage is that cascade boosters make it possible to increase the depth of subcriticality of the setup, intensify the fast pulse sharply, and decrease the background fission intensity manyfold. In principle, pulse parameters acceptable for practice can be achieved in a cascade periodic booster even without including the reactivity modulation factor. This means that using the cascade principle in periodic boosters will make them safer and improve their pulse parameters.