熔盐堆下舱室非能动冷却系统的优化设计  

Optimal design of passive cooling system for the reactor lower cavity of molten salt reactor

作　　者：梅牡丹[1,2] 周翀 傅瑶 邹杨[1,2] 王纳秀 MEI Mudan;ZHOU Chong;FU Yao;ZOU Yang;WANG Naxiu(Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海应用物理研究所,上海201800 [2]中国科学院大学,北京100049

出　　处：《核技术》2024年第8期107-118,共12页Nuclear Techniques

基　　金：中国科学院战略性先导科技专项(No.XDA02010000)、中国科学院上海应用物理研究所堆芯模块化理论与比选研究(No.SINAP-QYJS-202202)资助~~。

摘　　要：熔盐堆下舱室非能动冷却系统是确保反应堆安全运行的重要保障,其结构设计是热工水力设计中的重要一环,其功能是保证熔盐堆下堆舱所有设备在反应堆正常运行时不超温,同时在事故工况下,能够最大程度地导出堆芯衰变热。基于一种热功率为153 MWt的百兆瓦级熔盐堆的概念设计,建立了熔盐堆下堆舱的1/4结构模型,使用ANSYS FLUENT 20.1软件进行下堆舱三维流场与温度场的数值模拟,通过优化下舱室非能动冷却系统的结构布局、空气环腔的结构尺寸、隔热板上保温棉厚度以及进风管的入口位置,使得下舱室内双通道非能动空冷系统的热屏蔽效果最好,且在事故工况下导出堆芯衰变热最多。结果表明:改变空冷系统中空气环腔的结构尺寸对下堆舱热屏蔽结果的影响很小;在空冷系统的中间隔板上增加保温棉可以显著降低侧面混凝土墙的温度;冷却系统的进风管入口位置距离空冷环腔顶端越近热屏蔽效果越好。据此最终设计出了一种新型的下舱室内双通道非能动空冷系统,达到了153 MWt熔盐堆下堆舱的屏蔽冷却的设计要求。为未来大功率熔盐堆下舱室内非能动余热排出系统的工程优化设计提供了重要参考。[Background]The passive cooling system for the reactor cavity of the molten salt reactor(MSR)is an important guarantee to ensure the safe operation of the reactor,is one of the four engineered safety features for the MSR,and its structure design is an important part of the thermal hydraulic design.[Purpose]This study aims to find out a suitable passive reactor cavity cooling system(RCCS)to meet the requirements of thermal shielding design for the lower reactor cavity of the MSR,and maximize the removal of reactor core decay heat under accident conditions.[Methods]Firstly,based on the design parameters of a 153 MWt MSR,a 1/4 geometric model of the lower reactor cabin of this MSR was established.Then,ANSYS FLUENT 20.1 software was employed to conduct threedimensional numerical simulation of the flow filed and temperature filed for the lower reactor cabin,the influence of thermal shielding of the lower cavity was analyzed by changing the structure and layout of the passive RCCS,the structure sizes of the passive RCCS with double channel,the thickness of thermal insulation cotton on the intermediate thermal shielding plate and the position of the air inlet pipe.Finally,a new and suitable structure of passive RCCS was proposed after step-by-step improvements for a 153 MWt MSR.[Results]The simulation results show that the optimized new-style passive air-cooling system with a double channel in the lower reactor cavity is the best among the three structures.Changing the width of the RCCS has little effect on the thermal shielding results of the lower reactor cabin whilst increasing the thickness of thermal insulation cotton on the intermediate thermal shielding plate of the RCCS can significantly reduce the temperature of the inner surface of the concrete wall.The closer the inlet position of the air inlet pipe is to the top of the RCCS,the better the thermal shielding effect.Based on above results,a new-style passive air-cooling system with double channel in the lower cavity is designed to completely dsatisfy the requir

关 键 词：熔盐堆下舱室 双通道非能动冷却系统 热屏蔽设计 结构优化 计算流体力学 

分 类 号：TL334[核科学技术—核技术及应用]