Failure Fraction Calculation of the TRISO-Coated Particle Using X-Ray Computed Tomography

Libing Zhu,Yu Zhou,Jianxun Zhao,Xiangang Wang,Xincheng Xiang,Jariah Mohamad Juoi

doi:10.1155/2021/2420526

Abstract

The geometrical shape of the TRISO-coated particle is closely related to its performance and safety. In this paper, models were set up to study the failure fraction of TRISO particle, considering the real asphericity induced by manufacturing uncertainties. TRISO is simplified as a pressure vessel model, and micro X-ray CT was employed to detect the real geometrical shape. Key geometrical parameters, thickness and volume of the real particle, were then obtained with the 3D measurement method and input into PANAMA code (a German code for fuel performance simulation). Release fraction of fission gas and failure fraction of the TRISO-coated particle were revised with the aforementioned parameters with more accuracy and compared with those of the spherical particle. Obvious increment of failure fraction of the particle is found, which may contribute to the release of fission products.

Highlights

Tri-structural isotropic (TRISO) particle is the core fuel form for the Generation-IV, high temperature gas-cooled reactor as well as very high temperature reactor, molten salt reactor, and gas-cooled fast reactor due to its ability to retain fission product during severe accident condition at temperature up to 1600°C
TRISO-coated particle is simplified as a pressure vessel (PV) model, only considering the silicon carbide (SiC) layer because the SiC layer is the main stress holder and fission gas retention barrier
Pressure Vessel Model. e following equation deduction of PANAMA shows the theoretical relationship between failure fraction and geometrical parameters used in this paper, reproduced from references [9, 10]

Summary

Introduction

Tri-structural isotropic (TRISO) particle is the core fuel form for the Generation-IV, high temperature gas-cooled reactor as well as very high temperature reactor, molten salt reactor, and gas-cooled fast reactor due to its ability to retain fission product during severe accident condition at temperature up to 1600°C. If the stress of the SiC layer exceeds the tensile strength of it, the pressure vessel will fail

Methods

Results

Conclusion