氡子体气溶胶多孔撞击式采样器的设计与实现  

Design and implementation of a porous impingent sampler for radon progeny aerosoll

作　　者：谭至宇 陈凌[1] 程卫亚[1] 陈亮平[1] 马天赐 TAN Zhiyu;CHEN Ling;CHENG Weiya;CHEN Liangping;MA Tianci(China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《核技术》2023年第5期51-59,共9页Nuclear Techniques

摘　　要：氡子体气溶胶粒径是氡子体内照射剂量转换系数关键参数,研制氡子体气溶胶粒径测量装置开展对环境氡子体气溶胶粒径分布测量是必要的。惯性冲击器是一种广泛应用的颗粒物分级采样器,本文分析了几类常见的惯性冲击器,基于空气动力学理论与相关研究基础,设计了一种切割粒径为1μm的多孔撞击式采样器。利用计算流体动力学(Computational Fluid Dynamics,CFD)分析软件Fluent以及离散相模型对多孔撞击式采样器结构的收集板直径、收集板与内壁距离、喷嘴距离、喷嘴与收集板距离、喷嘴高度等设计参数进行模拟与分析,得到了一组优化设计参数,并在实验室用GRIMM11-D空气动力学粒度仪进行了标定。结果表明:多孔撞击式采集器的喷嘴距离(D)、喷嘴高度(T)、喷嘴到收集板的距离(S)与喷嘴直径(W)的关系在D/W=1.5~3.5、T/W=1~5、S/W=1范围内,实验标定结果为d_(p50)=(1±0.07)μm,σ_(g1)=1.33,σ_(g2)=1.35与CFD数值模拟的结果基本吻合,该冲击器切割粒径满足实际应用需求。[Background]Aerosol particle size of radon progeny is the key parameter of the radiation dose conversion coefficient in radon progeny.It is necessary to develop a measuring device for the aerosol particle size of radioactive aerosol to measure the aerosol particle size distribution of environmental radon progeny.Inertial impactor is a kind of widely used particulate classification sampler.[Purpose]This paper aims to design and implement an impactor applicable to radon progeny aerosol with a cutting size of 1μm.[Methods]First of all,several kinds of inertial impactors were analyzed on the basis of aerodynamic theory,the design parameters of the impaction sampler structure,such as the diameter of the collecting plate,the distance between the collecting plate and the inner wall,the distance between the nozzle and the collecting plate,the height of the nozzle,were simulated by using computational fluid dynamics(CFD)analysis software Fluent and discrete phase model.Then,based on simulation results,a set of optimized design parameters were obtained and a porous impingent sampler was implemented for radon progeny aerosol.Finally,this impactor was calibrated by a GRIMM11-D aerodynamics particle size analyzer in a laboratory.[Results]The optimized design parameters show that the nozzle distance D,the nozzle height T,the distance S from the nozzle to the collecting plate,and the nozzle diameter W have relationship of D/W=1.5~3.5,T/W=1~5,S/W=1.The experimental calibration results of designed porous impingent sampler are basically consistent with that of CFD numerical simulation with d_(p50)=(1±0.07)μm,σ_(g1)=1.33,σ_(g2)=1.35,and the cutting particle size of the impactors meets the practical application requirements.[Conclusions]This paper focuses on the design of an impactor sampler.Through simulation and comparison tests with ELPI+instrument,the effective cutting of 1μm particle size is realized,which provides convenience and ideas for the further optimization design and online particle size fractional measurement of

关 键 词：氡子体 惯性冲击器 参数设计 模拟验证 

分 类 号：X837[环境科学与工程—环境工程]