核反应堆严重事故下气溶胶动态吸湿增长机理研究  

Dynamic Hygroscopic Growth Mechanism of Aerosol under Severe Nuclear Reactor Accident

作　　者：王竞弘 于明锐 于溯源[1] 彭威[3] WANG Jinghong;YU Mingrui;YU Suyuan;PENG Wei(Key Laboratory for Thermal Science and Power Engineering of Ministry of Education,Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China;China Nuclear Power Engineering Co.,Ltd.,Beijing 100840,China;Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education,Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学能源与动力工程系热科学与动力工程教育部重点实验室,北京100084 [2]中国核电工程有限公司,北京100840 [3]清华大学核能与新能源技术研究院先进反应堆工程与安全教育部重点实验室,北京100084

出　　处：《原子能科学技术》2023年第11期2077-2085,共9页Atomic Energy Science and Technology

基　　金：国家重点研发计划(2020YFB1901401);国家自然科学基金(52176158)。

摘　　要：核电站发生严重事故之后,安全壳内可溶性气溶胶会在高湿度环境下发生吸湿增长现象,并以改变气溶胶粒径、密度的方式显著影响原有的气溶胶动力学行为。为了描述吸湿平衡时间等气溶胶吸湿增长的过程参量,表征吸湿增长过程时间尺度,本研究依据气溶胶吸湿的非平衡态过程构建了气溶胶动态吸湿模型,综合考虑吸湿过程中蒸汽质量守恒、能量守恒关系以及表面蒸汽压对气溶胶吸湿增长行为的影响,分析了气溶胶粒径变化率、吸湿平衡时间等吸湿过程参量。结果表明,在高湿度工况下,吸湿增长行为对小粒径颗粒的影响尤为显著。同时,吸湿过程中粒径变化率与时间呈对数变化规律,而吸湿平衡时间与粒径呈近似线性变化特征。After a severe accident in a nuclear power plant,the nuclear fuel and fission products inside the core will leak into the nuclear reactor containment vessel in the form of radioactive solid particles,and disperse in the containment space to form aerosols.These aerosols are important carriers of radioactive materials,and are also the key source items of radioactive fission products released into the environment under serious accidents.Besides,serious accidents in nuclear reactors are often accompanied by the loss of coolant accidents in primary pipe sections,resulting in a high-temperature and humid environment with relative humidity close to saturation in the containment.Under such accident conditions,the soluble aerosol in the containment vessel will undergo hygroscopic growth.The particle size will increase significantly due to the absorption of water vapor,and the particle density will also change significantly.Then the kinetic properties of aerosols will change,thus affecting the natural removal,migration and evolution of aerosols in the original containment,which is of great significance for the study of radioactive removal in the containment after serious accidents in nuclear power plants.In order to describe the process parameters of aerosol hygroscopic growth,such as hygroscopic equilibrium time,and characterize the time scale of hygroscopic growth process,an aerosol dynamic hygroscopic model based on the non-equilibrium process of aerosol hygroscopic growth was constructed,considering the relationship between vapor mass conservation and energy conservation during hygroscopic process,as well as the influence of surface vapor pressure on aerosol hygroscopic growth behavior.The aerosol dynamic hygroscopic model takes into account the mass conservation between the vapor phase and the energy change caused by vapor condensation.The surface vapor pressure of the particles was determined by the Kelvin effect and the solute effect.Based on the aerosol dynamic hygroscopic model,the parameters of the hygroscopic pr

关 键 词：核反应堆严重事故 气溶胶 吸湿增长 机理模型 

分 类 号：TL364.4[核科学技术—核技术及应用]