Numerical Research on Irradiation-Thermal-Mechanical Coupling Behavior of FCM Fuel

User defined subroutines were coded under the calculation frame of ABAQUS software, and then, the irradiation-thermal-mechanical coupling behavior simulation method of fully ceramic micro-capsuled（FCM） fuel was preliminary established. With this simulation method, the in-pile behaviors of TRISO particle were modeled. Compared with the BISON calculation results, the validity of this simulation method was tested. Subsequently, the irradiation-thermal-mechanical coupling behavior of FCM fuel was modeled. The simulation results showed that the temperature distribution and stress distribution of FCM fuel exhibited a strong non-uniformity. The fission gas release had a strong effect on the mechanical performance of FCM fuel. The hoop stresses and temperature distribution of FCM fuel were not sensitive to transient power increasing.