摘要
钠冷快堆作为第四代核反应堆的代表性堆型,其堆芯热工水力特性直接影响反应堆的安全运行。针对钠冷快堆燃料组件结构复杂、传统计算流体动力学(Computational Fluid Dynamics,CFD)模拟计算量大的问题,本研究采用多孔介质模型开展堆芯热工水力分析。研究以中国实验快堆(China Experimental Fast Reactor,CEFR)为对象,建立了包含81个六边形燃料组件的计算模型,并将组件内复杂结构转化为多孔介质模型的阻力系数。为提高计算精度,采用分区建模方法将堆芯划分为4个特征区域,同时运用共轭传热方法对组件间隙流动(盒间流)及其周边结构进行精细化建模。结果表明,多孔介质模型能够准确预测堆芯热工水力特性,压力降计算误差仅为0.7%,且计算效率较传统CFD方法显著提升。此外,盒间流对冷却剂整体流动分布的影响较小,在正常稳态工况下可忽略不计。本研究为钠冷快堆堆芯设计优化提供了重要参考。
[Background]Sodium-cooled fast reactors(SFRs)represent a critical advancement in fourth-generation nuclear technology,where accurate thermal-hydraulic characterization is vital for ensuring operational safety and efficiency.The complex geometry of SFR fuel assemblies presents significant challenges for conventional Computational Fluid Dynamics(CFD)approaches.[Purpose]This study aims to develop and validate an optimized porous media methodology to facilitate efficient yet precise CFD analysis of SFR core thermal-hydraulics.[Methods]The investigation examined the China Experimental Fast Reactor(CEFR)core configuration,comprising 81 hexagonal fuel assemblies.Firstly,the porous media model integrated anisotropic permeability tensors to account for directional flow resistance effects induced by wire-wrap spacers.Momentum source terms were calibrated using experimental pressure drop data.Then,the computational domain was divided into four distinct regions to accommodate spatial variations in power distribution and coolant flow patterns.Additionally,to explore the influence of inter-wrapper flow(IWF)on the core's thermal-hydraulic state,modeling was performed on the inter-wrapper flow and its surrounding components.Finally,the conjugate heat transfer method was employed to calculate the inter-wrapper flow,and results were compared with the conventional CFD approach.[Results]Comparison results demonstrate that the porous media model successfully predicts core thermal-hydraulic behavior with a maximum deviation of 0.7%in pressure drop compared to experimental benchmarks,and computational efficiency is significantly enhanced relative to full-resolution CFD.The inter-assembly gap flow contributes minimally to the total coolant redistribution,confirming its negligible impact on overall core performance.[Conclusions]The proposed porous media model offers a computationally efficient yet accurate alternative for SFR core analysis,demonstrating strong potential for engineering applications.The findings indicate that inter-assembly gaps can be safely disregarded in large-scale simulations without substantial loss of accuracy.This work provides valuable insights for optimizing SFR core design and improving safety assessments.
作者
孙雨琛
陈广亮
赵强
田逸之
李梦来
SUN Yuchen;CHEN Guangliang;ZHAO Qiang;TIAN Yizhi;LI Menglai(School of Nuclear Science and Technology,Harbin Engineering University,Harbin 150001,China)
出处
《核技术》
北大核心
2025年第7期151-160,共10页
Nuclear Techniques
基金
国家自然科学基金(No.51909045)
中国核工业集团公司青年人才研究项目(No.CNNC2019YTEP-HEU01)资助。
关键词
钠冷快堆
堆芯
热工水力
多孔介质
高效
Sodium-cooled fast reactor
Reactor core
Thermal-hydraulic
Porous media
High efficiency
