【作者】 景恒森； 张昊春； 张冬； 邓超；

【Author】 JING Hengsen;ZHANG Haochun;ZHANG Dong;DENG Chao;Harbin Institute of Technology;

【机构】 哈尔滨工业大学能源科学与工程学院；

【摘要】 钠冷快堆作为第四代核能系统的核心堆型,其复杂流道内的热工水力特性直接影响系统能效与安全性。本研究基于热力学第二定律中的熵产分析方法,通过Fluent软件对钠冷快堆内典型流道的热工水力行为开展数值模拟研究,主要内容包括:(1)建立单圆管钠流动模型,验证其准确性,利用UDF功能自编程计算熵产率,分析不同发展高度处的熵产分布特性,并通过无量纲熵产Ns、总熵产S、Bejan数Be和Ep等参数评估不可逆性损失;(2)构建带绕丝燃料棒束模型,分析其流场温度和速度分布,讨论不同流速条件下的熵产机制及分布规律,评估热流不可逆性特征。研究结果表明,钠在复杂流道中的能量耗散呈明显的非均匀性与多尺度特征。本文的分析结果可为钠冷快堆的热工优化设计与能量效率提升提供理论依据与工程参考。更多还原

【Abstract】 As a core reactor type in Generation Ⅳ nuclear energy systems,the sodium-cooled fast reactor(SFR) exhibits complex thermal-hydraulic behavior within its flow channels,which directly affects system efficiency and safety.In this study,numerical simulations were conducted using Fluent based on the entropy generation analysis derived from the second law of thermodynamics to investigate the thermal-hydraulic characteristics in typical SFR channels.The main contents include:(1) establishing a single circular tube model for liquid sodium flow and verifying its accuracy;using a user-defined function(UDF) to calculate entropy generation rates;analyzing entropy generation distributions at different developing sections;and evaluating irreversibility through dimensionless entropy generation number Ns,total entropy generation S,Bejan number Be,and performance evaluation criterion Ep.(2) Constructing a wire-wrapped fuel rod bundle model to analyze temperature and velocity fields,discuss entropy generation mechanisms under various flow velocities,and evaluate thermal irreversibility characteristics.The results reveal that energy dissipation in sodium flow exhibits pronounced spatial nonuniformity and multiscale features.The findings provide theoretical guidance and engineering reference for optimizing thermal-hydraulic design and improving energy efficiency in sodium-cooled fast reactors.更多还原