弥散型板状燃料元件跨尺度耦合特性计算与分析  

Calculation and Analysis of Multiscale Coupling of Dispersion Plate-type Fuel

作　　者：向烽瑞 贺亚男 巫英伟[1] 秋穗正[1] 苏光辉[1] Xiang Fengrui;He Yanan;Wu Yingwei;Qiu Suizheng;Su Guanghui(School of Nuclear Science and Technology,Xi’an Jiaotong University,Xi’an,710049,China)

机构地区：[1]西安交通大学核科学与技术学院,西安710049

出　　处：《核动力工程》2024年第S2期93-101,共9页Nuclear Power Engineering

基　　金：中核集团领创科研项目。

摘　　要：弥散型板状燃料两相弥散材料的多尺度特点对其性能研究提出了挑战。为准确分析与评价U_(3)Si_(2)/Al弥散型板状燃料在堆内的性能,在已有的U_(3)Si_(2)/Al弥散型芯体的等效物性、行为模型基础上,针对等效芯体较为复杂的蠕变特性,建立其蠕变衰减系数模型以准确模拟两相复合材料的蠕变行为。同时,构建了三维燃料板模型、一维颗粒球模型,并提出了将三维燃料板模型与一维颗粒球模型耦合的跨尺度耦合方法,以在宏观分析的同时,获取燃料芯体各部位微观颗粒行为。基于跨尺度多物理场耦合分析工具,开展针对弥散型燃料的多物理场分析,并对燃料颗粒的尺寸与体积份额的影响进行了评估。结果显示,增加颗粒的尺寸和体积份额只略微提高燃料中心温度,影响可忽略;当体积份额从30%提升到40%时,燃料颗粒应力增加11.6%。The multi-scale characteristics of two-phase dispersion materials in dispersion-type plate fuel pose challenges to its performance research.To accurately analyze and evaluate the in-pile performance of U_(3)Si_(2)/Al dispersion-type plate fuel,based on the existing equivalent physical properties and behavior model of U_(3)Si_(2)/Al dispersion fuel meat,the creep attenuation coefficient model was established to accurately simulate the creep behavior of two-phase composites,particularly focusing on the complex creep characteristics of the equivalent fuel meat.Additionally,a three-dimensional macroscopic fuel plate model and a one-dimensional sphere model were constructed,and a multi-scale coupling method was proposed to couple these models,enabling simultaneous simulation at both scales.Based on the multi-scale multi-physics coupling analysis tool,the multi-physical field analysis of U_(3)Si_(2)/Al dispersion-type fuel was conducted,and the impact of fuel particle size and volume fraction was evaluated.The results inidcate that increasing the particle size and volume fraction only slightly increases the central temperature of the fuel;however,when the volume fraction increases from 30%to 40%,the fuel particle stress increases by 11.6%.

关 键 词：弥散型板状燃料 等效蠕变 跨尺度耦合 微观燃料颗粒 

分 类 号：TL333[核科学技术—核技术及应用]