Published May 1974 | Version v1
Report

Temperature distribution around a plutonium spot in the ATR fuel pin

  • 1. Power Reactor and Nuclear Fuel Development Corp., Tokyo (Japan)

Description

The behavior of mixed oxide fuel (PuO2 - UO2) in accidental power excursion is important for the safety of thermal reactors. In ATR (Advanced Thermal Reactor), the thermal effect of a PuO2 spot on cladding must be taken into consideration to ensure the integrity of fuel pins. This effect becomes maximum when the spot exists on the periphery of a fuel pellet adjacent to cladding. Calculation of temperature distribution was made by the iteration method. For the PuO2 spot, its hemisphere is taken, which exists on the periphery of a pellet with the flat face facing the inner wall of cladding. It was found that the existence of a PuO2 spot has large influence on the region near the inner surface of cladding as compared with the outer surface. With zircaloy-2 cladding, 300 μm may be the maximum permissible radius of the PuO2 hemisphere for maintaining the integrity of pins under calculated conditions. (Mori, K.)

Additional details

Publishing Information

Imprint Title
Semi-annual progress report of Power Reactor and Nuclear Fuel Development Corporation, Tokai Works
Imprint Pagination
p. 40-47.
Report number
PNCT--831-74-01