Improvement on the plasma excitation probability of aerosol particles based on aerodynamic lens

Abstract

Aerodynamic lenses can increase the local particle number density of the aerosol beam. The particle number density of aerosol has an important effect on the excitation probability and spectral intensity of laser-induced plasma. Therefore, aerodynamic lenses have the potential to improve the identification efficiency of Laser Induced Breakdown Spectroscopy (LIBS) in aerosol real-time monitoring. In this study, the effects of an aerodynamic lens on laser excited aerosol particles were developed by experiments and simulations. The process of aerosol beam passing through an aerodynamic lens was simulated by using the CFD software FLUENT. The simulation results show that the setup can increase the aerosol concentration by three orders of magnitude. The Aerosol Focusing-Laser Induced Breakdown Spectroscopy (Aerosol Focusing-LIBS) experimental setup is established. The experimental and simulation results are in good agreement. And the experimental results show that the laser excitation probability has increased by about 5 times, the average intensity of the excitation spectrum has increased by about 3 times.