Korea Atomic Energy Research Institute

Korea Hydro Nuclear Power Co., Ltd.

Do-Hee Hahn

Tae-Joon Kim

Sung-Ho Kim

Jong-Hyuk Baek

Tae-Kyu Kim

Ji-Young Jeong

Jun-Hwan Kim

Woo-Gon Kim

Yeong-Il Kim

Chan-Bock Lee

Ser Gi Hong

Chang-Hee Han

Sang Ji Kim

A liquid-metal cooled fast reactor core having a nuclear fuel assembly constituted of nuclear fuel rods with varying cladding thicknesses in reactor core regions, in which: the nuclear fuel assembly () of a liquid-metal cooled fast reactor includes nuclear fuel assemblies (and) in inner, middle and outer reactor core regions, respectively, and is installed in a hexagonal duct () with nuclear fuel materials (--and-) surrounded by respective claddings (--and-), and the claddings (--and-) of a nuclear fuel rod () in the inner reactor core region, a nuclear fuel rod () in the middle reactor core region and a nuclear fuel rod () in the outer reactor core region are formed at different thicknesses. The reactor core can flatten power distribution using a single-enrichment nuclear fuel in the liquid-metal cooled fast reactor.

Liquid-metal-cooled fast reactor core comprising nuclear fuel assembly with nuclear fuel rods with varying fuel cladding thickness in each of the reactor core regions

Provided is a method of manufacturing a high strength ferritic/martensitic steel. The method includes melting a ferritic/martensitic steel, hot-working the melted ferritic/martensitic steel, normalizing the hot-worked ferritic/martensitic steel at a temperature of about 1050&#xb0; C. to about 1200&#xb0; C., tempering the ferritic/martensitic steel at a temperature of about 600&#xb0; C. or less, and leaving MX precipitates while preventing a MCprecipitate from being precipitated, and cold-working and thermal-treating the ferritic/martensitic steel in a multistage fashion, and precipitating MCprecipitates. Through the above described configuration, the high strength ferritic/martensitic steel that prevents a ductility from being deteriorated even in a high-temperature environment may be manufactured.

Manufacturing method of high strength ferritic/martensitic steels

A water leakage-acoustic sensing method in a steam generator of a sodium-cooled fast reactor, the method including: calculating a standard deviation and an average of an octave band by octave band analysis of an input signal sound received from at least one predetermined acoustic sensor; comparing the calculated standard deviation and the calculated average of the octave band, and determining a size of the octave band based on a comparison result; calculating an average of standard deviations of the octave band recomposed by the determined size and normalizing the average of standard deviations; applying a predetermined weight, established by a predetermined neural network learning algorithm, to the normalized average of standard deviations; and generating leakage determination data based on the average of standard deviations to which the weight is applied.

Water leakage-acoustic sensing method and apparatus in steam generator of sodium-cooled fast reactor using standard deviation by octave band analysis

Growing community of inventors

Daejeon, South Korea

Do-Hee Hahn