Preliminary Multi-Physics Performance Analysis and Design Evaluation of UO2 Fuel for LBE-Cooled Subcritical Reactor of China Initiative Accelerator Driven System

Guan Wang,Di Yun,Long Gu

doi:10.3389/fenrg.2021.732801

Abstract

The China initiative Accelerator Driven System (CiADS) and the corresponding lead-bismuth eutectic (LBE) cooled subcritical reactor, as the research subject of one of the major national science and technology infrastructure projects, are undertaken by the Institute of Modern Physics-Chinese Academy of Sciences (IMP-CAS). And in the first phase, UO2 fuels will be loaded in the subcritical core to test the coupling technology and achieve a long-term steady operation. A brief description of CiADS subcritical reactor, fuel assembly and fuel element are presented here, and a multi-physics performance analysis and design evaluation of CiADS UO2 fuel are carried out by means of the FUTURE code. FUTURE is a fuel performance analysis code to evaluate the synergy of phenomena occurring in the fuel element and their impact on the fuel design improvement for the liquid metal fast reactor, which was developed jointly by IMP-CAS and Xi’an Jiaotong University (XJTU). In this paper, the FUTURE code was modified and updated focusing on characteristics of CiADS fuels. Relocation and densification models were added. Results of the hottest fuel element, mainly concerning the thermo-mechanical behaviors, are discussed concerning both fuel and cladding performance on the basis of indicative design limits. According to the preliminary design, the CiADS UO2 fuel exhibits good performance, and the main safety parameters are far below the indicative limits. The Fuel Cladding Mechanical Interaction (FCMI) is not very serious, and the permanent cladding strains and Cumulative Damage Fraction (CDF) are small and even negligible thanks to the low level of fuel temperature and corresponding stress. However, some critical issues may still exist, especially on LBE corrosion near the coolant inlet, where protective oxide layers are very thin from BoL to EoL. The modeling is useful for providing feedback to the conceptual design of the CiADS LBE-cooled subcritical reactor and the update of FUTURE code.

Highlights

With human activities rapidly increasing and the development of society, energy and environment issues are more and more serious
The Belgian Nuclear Research Centre has been committed to the long-term development of MYRRHA (Multi-purpose hybrid research reactor for high-tech applications), which is the world’s first large-scale Accelerator Driven Subcritical system (ADS) that consists of an leadbismuth eutectic (LBE)-cooled fast reactor (LFR) that can operate in both critical and subcritical dual-modes driven by a highpower linear accelerator (Abderrahim et al, 2001)
The corresponding fuel design parameters presented above have been inputted into the FUTURE code, while neutronics analysis of the China initiative Accelerator Driven System (CiADS) subcritical reactor fuel pin has been carried out by means of the Monte Carlo code

Summary

Introduction

With human activities rapidly increasing and the development of society, energy and environment issues are more and more serious. The Accelerator Driven Subcritical system (ADS), which was originally proposed by Rubbia et al (1995), has been receiving increased attention as a potential technology for both energy production and nuclear waste transmutation (Wade 2000). The concept of ADS systems is based on coupling three main parts, including particle accelerator, heavy metal target and a subcritical reactor. The Belgian Nuclear Research Centre has been committed to the long-term development of MYRRHA (Multi-purpose hybrid research reactor for high-tech applications), which is the world’s first large-scale ADS that consists of an LBE-cooled fast reactor (LFR) that can operate in both critical and subcritical dual-modes driven by a highpower linear accelerator (Abderrahim et al, 2001). CiADS (Zhan and Xu 2012; Xu, He, and Luo 2015; Peng et al, 2017) is devoted to establishing an experimental and demonstration ADS facility globally

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Conclusion