Fission Product Release and Survivability of UN-Kernel LWR TRISO Fuel

Journal Article · Wed Jan 01 04:00:00 EST 2014 · Journal of Nuclear Materials

DOI:https://doi.org/10.1016/j.jnucmat.2013.10.034· OSTI ID:1134636

Besmann, Theodore M ^[1]; Ferber, Mattison K ^[1]; Lin, Hua-Tay ^[1]

---

1. ORNL

A thermomechanical assessment of the LWR application of TRISO fuel with UN kernels was performed. Fission product release under operational and transient temperature conditions was determined by extrapolation from range calculations and limited data from irradiated UN pellets. Both fission recoil and diffusive release were considered and internal particle pressures computed for both 650 and 800 m diameter kernels as a function of buffer layer thickness. These pressures were used in conjunction with a finite element program to compute the radial and tangential stresses generated with a TRISO particle as a function of fluence. Creep and swelling of the inner and outer pyrolytic carbon layers were included in the analyses. A measure of reliability of the TRISO particle was obtained by measuring the probability of survival of the SiC barrier layer and the maximum tensile stress generated in the pyrolytic carbon layers as a function of fluence. These reliability estimates were obtained as functions of the kernel diameter, buffer layer thickness, and pyrolytic carbon layer thickness. The value of the probability of survival at the end of irradiation was inversely proportional to the maximum pressure.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: NE USDOE - Office of Nuclear Energy
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1134636
• Journal Information: Journal of Nuclear Materials, Journal Name: Journal of Nuclear Materials Journal Issue: 1-3 Vol. 448; ISSN 0022-3115
• Country of Publication: United States
• Language: English