Research On Measurement Technology Of Particle Sizing And Concentration Based On Backscattering

Particles exist in everywhere in the nature,and it is closely related to people's production and life.With the continuous development of science and technology,the study of particle is becoming more and more deeper.The particle size and concentration are regarded as the important parameters of particles which become the main research object.This thesis designed the experiment of using light backscattering method to measure particle size and concentration,measured the particle size distribution and concentration of polystyrene particle system dispersed in homogeneous medium.This paper is based on the Mie scattering theory,deduced and calculated Mie scattering coefficient an,bn and scattering angle function ?n,?n in detail,and obtained the relationship between the scattering intensity and particle size distribution curve.And PT Algorithm was used in non-binding mode,and made a simulation experiment on measurement range of particle size of polystyrene particle system scattering in the water.The simulation result showed that the selection of upper and lower bound for particle size measurement range has much effect on the inversion result,and the reasonable measurement range of particle size was determined.RED TIDE USB650 fiber optic spectrometer was choosed to carry out the secondary development work of the spectrometer through the spectrum development platform OmniDriver,and explored the experiment of measuring the particle size distribution of light backscattering on standard polystyrene particles whose average particle size is 8?m,coordinating with Tungsten halogen light source with HL-2000 and optical fiber reflective sensor with R-series,as a result,the experimental result has a deviation of 0.5?m with the standard particle size.This thesis deduced the theory relationship between backscattering intensity and particle concentration in the section for using light backscattering method to measure particle concentration.R6350 photomultiplier tube was selected as the light backscattering detector and chooses UV LED of the best response spectrum of type R6350 as light source in order to improve the detection limit of the particle concentration.The experiment that of calibrate and measure polystyrene particles were carried out,the result of the relative error of measurement is 7.9%.The measurement technology of light back-scattering particle size and concentration has advantages of receiving and sending in the direction and not affected by extreme concentration.It has a broad development prospect in environmental monitoring,particles production,petrifaction and other fields.