摘要
为了研究开放式非能动空冷余热排出系统特性,本文基于CFD方法建立了系统的数值计算模型,从余排系统内外流道的温度场、速度场、传热百分比和换热系数等角度分析了热辐射发射率和隔热层热阻等因素对自然循环传热能力的影响。本文的研究工况范围是:3×10^(3)≤Re≤9×104,6×10^(6)≤Ra≤3×109,8.89×10^(-7)≤Bo≤1.02×10^(-4)。计算结果表明:加热通道内存在对流换热的热入口效应和辐射换热的端部效应。热辐射不直接传热给空气,但是改变了壁面间对流换热百分比。系统内的自然循环由上升和下降通道间的密度差驱动,随着隔热层热阻的变化,当热阻小于1.46×10^(-3) K/W,自然循环驱动力快速下降,压力容器壁面传热恶化。
To study the characteristics of the passive open-ended air-cooling residual heat removal system,a computational fluid dynamics-based numerical calculation model of the system was established.The influences of the radiation emissivity and thermal resistance of the thermal insulation layer on the natural circulation heat transfer of the residual heat removal system were analyzed considering the local temperature field,velocity field,heat transfer share,and heat transfer coefficient.The conditions were as follows:3×10^(3)≤Re≤9×104,6×10^(6)≤Ra≤3×10^(9),8.89×10^(-7)≤Bo≤1.02×10-4.The calculation results indicated the existence of heat entrance effects on convective heat transfer and open-ended effects on radiative heat transfer in the heating channel.Thermal radiation did not directly transfer heat to the air but influenced the portion of convective heat transfer between the walls.The natural circulation in the system was driven by the density difference between the ascending and descending channels.With the change in the thermal resistance of the insulation layer,at a thermal resistance of R c<1.46×10-3 K/W,the driving force of the natural circulation rapidly decreased,and the heat transfer on the pressure vessel wall deteriorated.
作者
邹文重
温济铭
胡相杰
于沛
李丽娟
ZOU Wenzhong;WEN Jiming;HU Xiangjie;YU Pei;LI Lijuan(China Nuclear Power Engineering Co.,Ltd.,Beijing 100840,China;College of Nuclear Science and Technology,Harbin Engineering University,Harbin 150001,China)
出处
《哈尔滨工程大学学报》
EI
CAS
CSCD
北大核心
2023年第7期1175-1180,共6页
Journal of Harbin Engineering University
关键词
空冷
余热排出系统
数值模拟
自然循环
温度场
速度场
热辐射
发射率
air-cooling
decay heat removal system
numerical analysis
natural circulation
temperature field
ve-locity field
heat radiation
emissivity
