Effects of Fission Heat and Fuel Swelling on the Thermal-mechanical Behaviors of Dispersion Fuel Elements

Abstract

Thermal-mechanical behaviors of dispersion fuel elements were investigated through the finite element method. A representative plate element was developed for the thin fuel plate considering both the heat transfer conditions on its boundaries and the mutual actions of large numbers of fuel particles immersed. This research focuses on the thermal elastoplastic behaviors of the metal matrix. It was found that the thermal stresses could be of rather high level due to the high temperature working conditions, and that the temperature field was not homogeneous because of the fission heat; Irradiation induced swellings might further enhance the Mises stresses and the equivalent plastic strains very strongly. The heat transfer coefficients might have a large impact on the temperatures and the thermal-mechanical behaviors as well.

Keywords:

• dispersion fuel element
• metal matrix particle composite
• thermal-elastoplastic analysis
• fission heat
• swelling
• heat transfer

ACKNOWLEDGEMENTS

The authors acknowledge the support of the Natural Science Foundation of China (10772049), the Natural Science Foundation of Shanghai (06ZR14009), The Pujiang Scholar Program and The Natural Science Foundation of Shanghai post-doctor.