[2D15-21] FP Chemical Behavior

[2D20] FP chemistry in a high temperature region of LWR under a severe accident

(6)Improvement of ruthenium release model from a nuclear fuel under a LWR severe accident

*Jiazhan Liu¹, Naoya Miyahara¹, Shuhei Miwa¹, Masahide Takano¹, Masahiko Osaka¹ (1. JAEA)

Keywords:Ruthenium, Mo-Ru-Pd-Rh alloys , Vaporization, Diffusivities

To improve the ruthenium (Ru) release model from a nuclear fuel in a severe accident, the oxidation and vaporization behaviors of Ru from Mo-Ru-Pd-Rh alloys were investigated. A mass transfer theory between bulk atmosphere and the surface of the alloy was applied for the Ru release model. The diffusivities of vaporizing RuO_x in air and argon gas could have been derived experimentally.