热辐射特征参数对快堆锥形顶盖空间换热特性影响的研究  

Study on the Influence of Thermal Radiation Characteristic Parameters on Roof Slab Space Heat Transfer Behaviors in Fast Reactor

作　　者：冯佳琪 陆道纲[1,2] 张钰浩 于宗玉[1,2] FENG Jiaqi;LU Daogang;ZHANG Yuhao;YU Zongyu(China Institute of Atomic Energy,Beijing 102413,China;China Academy of Engineering Physics,Beijing 621900,China)

机构地区：[1]华北电力大学核科学与工程学院,北京102206 [2]非能动核能安全技术北京市重点实验室,北京102206

出　　处：《核科学与工程》2024年第1期55-62,共8页Nuclear Science and Engineering

摘　　要：池式钠冷快堆的钠池内充满高温液态钠,其上方覆盖有氩气,高温液态钠主要通过辐射换热及对流换热的方式向快堆主容器上部结构及氩气空间传递热量,其换热特性及其影响因素十分复杂。辐射发射率及液态钠蒸发形成的气溶胶层对主容器上部结构的热工水力特性会造成一定影响。因此,为保证主容器上部结构在不同温度载荷下的安全性与稳定性,十分必要获取不同辐射发射率及不同气溶胶层分布下的温度分布。本研究建立大型池式钠冷快堆主容器上部锥形顶盖空间(以下简称“锥顶盖”)数值计算模型,开展数值模拟计算,得到不同发射率及气溶胶层厚度影响下锥顶盖的温度场。研究结果表明,发射率越高,锥顶盖斜肩及氩气空间温度越高;当气溶胶层存在于靠近钠液面的高度范围时(0~0.2 m),增加其厚度可使氩气空间局部温度升高,但对锥顶盖斜肩温度影响有限。发射率增高53%,则辐射换热量增加31.47%,格拉晓夫数(Gr)减少19.29%,辐射换热效果增强,自然对流效果减弱;气溶胶层高度由0增加到0~0.1 m时,对辐射换热量的吸收增加22.68%,格拉晓夫数(Gr)减少19.29%,气溶胶层高度由0~0.1 m增加到0~0.2 m时,透过气溶胶层的辐射换热量减少了0.04%,格拉晓夫数(Gr)增加了0.9%,辐射换热效果减弱,自然对流效果加强。This study investigates the complex heat transfer characteristics and influencing factors of the sodium pool in the pool-type sodium-cooled fast reactor(SFR),which is filled with hightemperature liquid sodium and covered with argon gas.Heat is mainly transferred to the reactor vessel superstructure and argon space by radiation and convection.The presence of radiation emissivity and the aerosol layer,resulting from the evaporation of liquid sodium,affects the thermal and hydraulic characteristics of the main vessel superstructure.Therefore,to ensure the safety of the reactor vessel superstructure under different temperature loads,it is crucial to determine the temperature distribution under different radiation emissivity and aerosol layer conditions.In this study,numerical simulations of the roof slab of the reactor vessel upper part in the pool-type SFR were conducted to determine the temperature field of the roof slab under the influence of different emissivity and aerosol layer thickness.The results show that increasing the emissivity of the radiation heat exchange by 53%increases the temperature of the roof slab sloping shoulder and argon space by 31.47%,while decreasing the Grashof number(Gr)by 19.29%,thereby enhancing the radiative heat exchange effect and weakening the natural convection effect.Furthermore,increasing the aerosol layer thickness in the height near the sodium surface(0~0.2 m)increases the local temperature of the argon space.However,the effect on the temperature of the roof slab sloping shoulder is limited.Increasing the height of the aerosol layer from 0 to 0~0.1 m decreases the radiation heat through the aerosol layer exchange by 22.68%,while decreasing the Gr by 19.29%.However,increasing the height of the aerosol layer from 0~0.1 m to 0~0.2 m only slightly decreases the radiative heat through the aerosol layer exchange by 0.04%and increases the Gr by 0.09%,weakening the radiative heat exchange and enhancing the natural convection effects.

关 键 词：快堆锥形顶盖空间 辐射换热 自然对流 发射率 吸收系数 

分 类 号：TL433[核科学技术—核技术及应用]