- ACTIVE ZONE OF A LEAD-COOLED FAST REACTOR

摘要

The active area of the reactor, the fuel element and the fuel assembly for producing the active area, is intended for use in a high-speed reactor having a nitride fuel, and a liquid metal coolant primarily in the form of molten lead and its alloys. A problem to be solved by the present invention is to create an active region having a void reactive effect and effective output flattening according to the radius of the active region. Wherein the active region comprises homogeneous uranium-plutonium nitride fuel, wherein the mass fraction of the fuel in the active region is at least 0.305 and comprises three portions: a central portion, a middle portion, and a peripheral portion, Forming fuel assemblies comprising fuel elements having geometrically identical shells but having fuel columns of different heights in the central portion, the middle portion, and the peripheral portion of the active region, wherein the radial distribution of the fuel over the volume of the active region Is a step-like shape in the longitudinal section. The radius of the central portion of the active region is 0.4 to 0.5 of the effective radius of the active region while the height of the fuel column in the fuel elements of the fuel assembly at the central portion is greater than the height of the fuel column within the fuel elements 0.5 to 0.8 of the height of the fuel column. The height of the fuel columns forming the stepped intermediate portion (with at least one step) for a diameter in the range of 0.5 to 0.85 of the effective diameter of the active region is dependent on the fuel elements arranged in the fuel assembly in the periphery of the active region Lt; RTI ID = 0.0 0.55 / RTI