多孔弥散微封装燃料元件多场耦合性能分析  

Analysis for multi-physics coupling performance of prismatic dispersed microencapsulated fuel

作　　者：李晨曦 李权[1] 黄永忠[1] 赵波[1] 王浩煜 刘仕超 李垣明[1] 陈平[1] LI Chenxi;LI Quan;HUANG Yongzhong;ZHAO Bo;WANG Haoyu;LIU Shichao;LI Yuanming;CHEN Ping(Science and Technology on Reactor System Design Technology Laboratory,Nuclear Power Institute of China,Chengdu 610213,China)

机构地区：[1]中国核动力研究设计院核反应堆系统设计技术重点实验室,四川成都610213

出　　处：《火箭推进》2024年第4期110-116,共7页Journal of Rocket Propulsion

基　　金：中国科协青年人才托举工程;核技术研发课题(HNKF202316(48));四川省杰出青年科技人才项目(2024NSFJQ0036)。

摘　　要：高温气冷堆是核热推进的主力候选堆型之一,燃料元件的性能直接决定了反应堆的性能,高温气冷堆的燃料元件形式众多,高安全性的弥散微封装燃料在高温气冷堆中具有极高的应用前景。因此,有必要针对高温气冷堆用弥散微封装燃料开展研究。提出将TRISO燃料颗粒弥散于SiC基体的多孔弥散微封装燃料的设计方案,并基于有限元分析软件COMSOL建立了三维热流固耦合分析模型,初步实现了该燃料元件性能分析,开展了不同冷却剂流量下的燃料元件热力行为分析。结果表明:流量越高,燃料元件最高温度越低,分别为1 340、1 250、1 180 K,远低于SiC材料熔点,无熔化风险;六棱柱内部的温度分布相对均匀,而六棱柱6个角处的温度分布相对不均匀;基体最大主应力出现在冷却剂流道周围,最大主应力最大值为95.6 MPa,其余位置整体最大主应力较小,最大主应力低于SiC材料断裂强度。High-temperature gas-cooled reactors are one of the main candidate reactors for nuclear thermal propulsion.The performance of the reactor is mainly influenced by the performance of the fuel element.There are many forms of fuel elements in high-temperature gas-cooled reactors,and high safety dispersed microencapsulated fuels have extremely high application prospects in high-temperature gas-cooled reactors.Therefore,the analysis for microencapsulated fuels for high-temperature gas-cooled reactors is needed.A prismatic dispersed microencapsulated fuel with TRISO particles dispersed in SiC matric was proposed in this paper.Based on the finite element analysis software COMSOL,a three-dimensional thermal-fluid-solid coupling analysis model was established to initially realize the performance analysis of the fuel element and carry out experiments under different coolant flow flux.The results show that the higher the flow rate,the lower the maximum temperature of the fuel element,which is 1340 K,1250 K and 1180 K respectively.The temperature is far lower than the melting point of SiC material and there is no risk of melting;the temperature distribution inside the hexagonal prism is relatively uniform,while the temperature distribution at the six corners of the hexagonal prism is relatively uneven.The maximum principal stress of the matrix appears around the coolant flow channel,with a maximum value of 95.6 MPa.The overall maximum principal stress at other locations is smaller,and the maximum principal stress is lower than the fracture strength of the SiC material.The prismatic dispersion microencapsulated fuel performance analysis method and research conclusions established in this article can provide guidance and reference for the subsequent design of this type of gas-cooled reactor fuel elements.

关 键 词：棱柱型 多孔弥散微封装燃料 多场耦合 

分 类 号：TL35[核科学技术—核技术及应用]