System and method for measuring overall average scattering characteristic of aerosol particles

Abstract

The invention provides a system and a method for measuring the total average scattering characteristic of aerosol particles. According to the measuring system, an inner cavity of an outer shell is used as a measuring area; an inner shell is arranged in the measuring area, the inner cavity serves as a sample pool, a pair of window sheets are arranged on the front and rear side walls, and aerosol particles are pumped into and out of an air inlet and an air outlet in the front and rear ends of the bottom; a laser light source emitted by a laser is arranged in the measuring area; laser beams in atleast four polarization states are formed through modulation of a polarizing prism and a first wave plate rotating wheel; a laser beam enters the sample pool through a small-hole diaphragm and the window sheet on the front side of the inner shell; scattered light formed after interaction with aerosol particles pumped from the air inlet is detected by a scanning polarization analysis module to obtain full Stokes parameters, and a laser beam transmitted after interaction with the aerosol particles goes out of the sample pool through the window sheet on the rear side of the inner shell, is reflected by a reflector and then is absorbed by a light trap. According to the invention, the requirement of in-situ nondestructive measurement of the total average scattering characteristic matrix full matrix element of the aerosol particles can be met.

Description

technical field [0001] The invention relates to the technical field of measuring the scattering characteristics of aerosol particles, and more specifically relates to a system and method for measuring the overall average scattering characteristics of aerosol particles. Background technique [0002] Aerosol particles affect planetary weather, climate, and geothermal balance through direct and indirect radiation effects, and can also reduce visibility and affect human health. The scattering characteristics of aerosol particles have always been a research hotspot. The research and detection of aerosol characteristics can play a positive role in weather forecasting, climate simulation prediction, environmental monitoring, and remote sensing applications. [0003] The scattering properties of particulate matter are usually measured with a nephelometer. Existing particle scattering characteristic nephelometers can be divided into four categories, in the form of array detectors, s...

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Problems solved by technology

However, most of these scattering nephelometers can only measure part of the matrix elements of the scattering characteristic matrix of aerosol particles, usually the first and second items of the matrix, and there are 16 elements in the scattering characteristic matrix; although O. The scanning polarization turbidity meter developed by et al. can measure the full matrix elements, but the device needs to collect, crush, aerosol samples and other pretreatments, and then spray them into the measurement area from the nozzle, which will destroy the aerosol collagen Some shapes, particle size distributions, and newly generated aerosols are obviously different from the source area of ​​aerosol collection, and in-situ measurement cannot be realized

At present, there is no scattering nephelometer that can simultaneously meet the requirements of in-situ non-destructive measurement of the overall average scattering characteristic matrix of aerosol particles and the full matrix elements.

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