[2I08-17] SiC

[2I12] The feasibility study on SiC composite fuel cladding for the Accident Tolerant Fuel to the existing PWR plants

(1)Evaluations of influence on core neutronics characteristics

*Kazuya Yamaji¹, Kazuki Kirimura¹, Shinya Kosaka¹, Shinichiro Yamashita² (1. Mitsubishi Heavy Industries, Ltd., 2. Japan Atomic Energy Agency)

Keywords:accident tolerant fuel, SiC composite, fuel cladding, PWR, neutronics characteristics

We evaluated neutronics characteristics of PWR core with SiC cladding fuel (the Accident Tolerant Fuel) by using the MHI core design code system GalaxyCosmo-S. In this study, we compared critical boron concentration, local power peaking, reactivity worth etc. between SiC and conventional Zircaloy cladding fuel cores. In the SiC cladding fuel core, shutdown margin is decreased because fuel temperature is higher due to lower heat conductivity of cladding material. The shutdown margin can be improved by control rods expansion and other characteristics do not significantly change. In the view point of neutronics, feasibility of the SiC cladding fuel core was confirmed.