温度对撞击器内颗粒沉积粒径影响的研究
STUDY ON THE INFLUENCE OF TEMPERATURE ON THE SIZE OF PARTICLES DEPOSITED IN IMPACTOR
彭慧 1池辉 2徐聪 1尹招琴 1包福兵 1凃程旭1
作者信息
- 1. 中国计量大学计量测试工程学院,杭州 310018
- 2. 福建省计量科学研究院,福州 350003
- 折叠
摘要
微颗粒的性质几乎与颗粒的粒径紧密相关,为研究气溶胶粒子特性,需获取颗粒粒径分布信息.惯性撞击器是一种基于惯性原理实现大气中不同粒径颗粒沉积分离的装置,在实际使用过程中,经历复杂多变的环境.文章利用拉格朗日多相(LMP)模型对撞击器内的气-固两相流动进行数值模拟,使用有限体积方法(FVM)研究了在绝热和换热两种情况下,气溶胶温度变化(-40℃～60℃)对颗粒沉积率的作用,并分析其对颗粒粒径分离的影响.结果表明:在壁面绝热情况下,随着气溶胶温度的升高,颗粒沉积位置由冲击板中心向边缘发散,颗粒收集效率逐渐降低,颗粒收集数量减少;在气溶胶和壁面换热情况下,随着气溶胶温度的升高,大颗粒沉积位置由冲击板中心向边缘发散,颗粒收集效率降低,小颗粒正好相反.此外,不同气溶胶温度下的颗粒收集效率曲线存在一个交点,交点两侧大小颗粒的收集效率随温度的变化情况相反.通过研究温度对撞击器颗粒收集的影响,可以对颗粒分径结果进行修正,获得更精确的粒径分布.
Abstract
The properties of microparticles are almost closely related to the particle size.In order to study the characteristics of aerosol particles,it is necessary to obtain particle size distribution information.The inertial impactor is a device based on the principle of inertia to realize the deposition separation of particles of different sizes in the atmosphere.During actual use,it experiences complex and changeable environments.In this paper,the Lagrangian multiphase(LMP)model is used to numerically simulate the gas-solid two-phase flow in the impactor.The effect of aerosol temperature variation(-40℃～60℃)on the particle deposition rate was investigated using the finite volume method(FVM)under both adiabatic and heat transfer conditions,and its effect on particle size separation was analyzed.The results show that:under the condition of wall adiabatic,as the temperature of the aerosol increases,the particle deposition position diverges from the center of the impact plate to the edge,the particle collection efficiency decreases,and the number of particle collection decreases gradually;in the condition of aerosol and wall heat transfer,as the temperature of the aerosol increases,the deposition position of large particles diverges from the center of the impact plate to the edge,and the collection efficiency of particles decreases,while the opposite is true for small particles.In addition,there is an intersection point in the particle collection efficiency curves at different aerosol temperatures,and the collection efficiency of large and small particles on both sides of the intersection point changes oppositely with temperature.By studying the influence of temperature on the impactor particle collection,the results of particle diameter separation can be modified and more accurate particle size distribution can be obtained.
关键词
惯性撞击器/气溶胶温度/颗粒沉积/颗粒收集效率/拉格朗日多相模型Key words
inertial impactor/aerosol temperature/particle deposition/particle collection efficiency/Lagrangian multiphase model引用本文复制引用
基金项目
国家自然科学基金(11972335)
福建省能源计量重点实验室开放基金(NYJL-KFKT-2022-03)
出版年
2024
NETL
NSTL
维普
万方数据