CONTROL ROD OF WATER-COOLED PRESSURIZED-VESSEL REACTOR Russian patent published in 1998 - IPC

FIELD: nuclear power engineering. SUBSTANCE: control rod has shell accommodating neutron absorber pile. The latter is built up of two parts one of which is made of material entering in reaction with neutrons ((n,α)), such as boron carbide. Other part first introduced in reactor core is made of dysprosium base material and its length is found from mathematical expression including length of neutron absorber pile and efficiencies of rods having different characteristics. According to mentioned expression, length of dysprosium base material part makes it possible to produce rod ma maximal mass considering variation in its absorbing capacity due to increase in specific content of dysprosium base material whose density is much higher than that of boron carbide. EFFECT: improved mass of control rod. 5 cl, 4 dwg