用于生物气溶胶质谱检测的泵送逆流虚拟切割器研究OA北大核心CSTPCD

Single particle aerosol mass spectrometer(SPAMS)can provide high time resolution and high sensitivity characteristics of particle size distribution and mass spectrometry composition data,and is widely used in the fields of atmospheric aerosol detection and atmospheric scientific research.In the atmospheric environment,sedimentation causes the concentration of large micron-sized parti-cles in the air to be much smaller than that of small sub-micron-sized particles,and there is an order of magnitude difference in the number of particles.In the detection of single particle aerosol mass spectrometry,particles are accelerated through aerodynamics and empowered,which makes small particles fly faster than large particles.This ultimately leads to a significant reduction in the detection probability of single particle mass spectrometry when analyzing large particles such as bioaerosols.Therefore,how to separate large particles from small particles has become the key to improving the effective detection of bioaerosol large particles by SPAMS.This study designed a pumped counterflow virtual impactor(PCVI).Through 3D modeling,computational fluid dynamics(CFD)simulation,actual experimental testing and detection of algae aerosol,the implementation principle,data simu-lation,and performance verification and practical application.It is combined with SPAMS to form a PCVI-SPAMS system with cutting capabilities for fine particles.Algae bioaerosol detection has con-firmed that the developed PCVI can effectively remove particles with a minimum particle size of less than 2 μm,successfully segment the background of small particles,and achieve expected results.