Nuclear reactor with reactivity control - and power distbtn cont by burnable reactor

摘要

Reactor core initially has excess reactivity so that a specified reactor power level is obtainable over a given period. At least one fuel rod of a bundle contains reactor poison for the purpose of controlling the excess reactivity. Poison density and disposition is selected so that the poison is self-shielding, with its control effect falling proportion to the reactivity fall in the core, so that it is consumed by the end of the operating period. Fuel in the immediate vicinity of the poison has a larger fission cross-section than that of similar fuel further from the poison.