标准气溶胶发生系统的建立与性能评估

针对气溶胶测量仪器校准和实验室气溶胶光学特性研究的需求,搭建了一套标准气溶胶发生系统,并对其性能开展了测试研究.系统采用恒定流量的雾化器产生气溶胶,经过扩散干燥管干燥以及电荷中和器带电中和后,产生标准气溶胶粒子.利用氯化钠样品对系统的性能进行了测试,结果表明,当样品溶液浓度增加时,系统雾化产生粒子的数浓度和粒径均随之增加;当载气气压增加,系统雾化产生粒子的数浓度随之增加,而粒径随之减小.在测试时间内,系统发生的多分散气溶胶粒子的几何平均粒径波动小于1%,总粒子数浓度波动小于2%,单分散气溶胶粒子数浓度的稳定性好于4%.

Development and performance evaluation of a standard aerosol generation system

We report on the development of a standard aerosol generation system for calibrating aerosol instrument and studying aerosol optical properties. The performance evaluation of the system was carried out with laboratory generated standard aerosol particles. The aerosol generation system consisted of a constant output atomizer to nebulize aqueous solution of aerosol samples, two silica gel diffusion dryers to dry the aerosol sample, and a neutralizer to generate standard polydispersed aerosol. The observed data indicated that the concentration and size of aerosol particles increased consistently with the increasing of aqueous solutions concentration. When the flow pressure increased, the particle concentrations kept on rising but the size decreased. During continuous operation, the deviations of the geometric mean size and total number concentration of polydispersed aerosol were smaller than 1% and 2%, respectively, and the stability of the concentration of monodisperse aerosol under different conditions was better than 4%.