Effective thermal conductivity and microstructure design of fully ceramic microencapsulated fuel pellet based on finite element calculations

Abstract

Abstract: To study the thermal conductivity of a fully ceramic microencapsulated (FCM) pellet, the sphere method was used to predict the effective thermal conductivity of the multilayered tri-isotropic (TRISO) particle by finite element method. Meanwhile, the effective thermal conductivity of the FCM pellet was calculated by a multi-scale equivalent representative volume element method and optimized by adjusting the content and distribution of TRISO particles. The simulation results showed that the effective thermal conductivity of the TRISO particle and FCM pellet can be predicted quickly and accurately by using the sphere method and the multi-scale equivalent method, and the effective thermal conductivity of the TRISO particle can be improved byadjusting the thickness of the SiC layer.An FCC-stacked microstructure using TRISO presented to makethe FCM pellet possesse higher content fuel particles and exhibits improved heat conduction performance.

Key words: FCM, TRISO particles, thermal conductivity, finite element method

CLC Number:

TB303

ZHANG Xu-dong,DENG Jun-kai, MA Da-yan, CAO Hui-ying, ZHANG Rui-qian, TANG Rui. Effective thermal conductivity and microstructure design of fully ceramic microencapsulated fuel pellet based on finite element calculations[J]. Journal of Lanzhou University of Technology, 2022, 48(2): 9-15.

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