Research On Aerosol Detection Method And System Structure Design Based On Angle Scattering Method

Research on the impact of changes in the atmospheric environment is an important research field that is highly concerned and urgently to be strengthened in the future sustainable development of our country.In response to the needs of real-time monitoring and component analysis of atmospheric particulate matter,this thesis carries out the detection method of atmospheric aerosol particulate matter based on the angular scattering method and System design research.First of all,on the basis of analyzing the light scattering theory and several methods of approximately solving the light scattering,the thesis studies the theoretical model of measuring particle size by the angle scattering method,and analyzes the different scattering angles and lighting angles.The relationship between the amount and the particle size,and the selection method of the optimal detection scattering angle and lighting angle is proposed.Secondly,according to the theoretical model of angular scattering particle detection,a measurement system based on the angular scattering particle detection principle is designed,and the modular design of the system’s functional modules is completed;the ray tracing simulation based on Monte Carlo method is used to simulate atmospheric aerosol particles.The light energy analysis of Mie scattered detection light uses SolidWorks modeling software to design and model the mechanical structure of each optical module to realize the selection of system light source and photodetector and the design of mechanical structural parts;further,to reduce the system The assembling error of each module during assembly reduces the interference of external vibration and other factors on the stability of the system.The structure of the system light source module,detection module and light trap module is optimized to improve the detection accuracy and stability of the system.Finally,the prototype of the angular scattering particle detection system was trial-produced and preliminary tests were carried out.Through the test of the system’s ability to detect scattered light of atmospheric particles of different sizes and attributes,the feasibility of the system design was preliminarily verified.