Aerodynamic particle size measurement by laser-doppler velocimetry

doi:10.1016/0021-8502(80)90030-0

Journal of Aerosol Science

Volume 11, Issue 2, 1980, Pages 139-150

https://doi.org/10.1016/0021-8502(80)90030-0 Get rights and content

Abstract

A method of measuring the aerodynamic diameter of aerosol particles is presented. Particles are accelerated in a converging nozzle and their velocity is measured near the exit with a laser-Doppler velocimeter. Nozzle parameters and flow conditions are chosen so that the particle velocity depends primarily on aerodynamic diameter.

Experimental studies utilizing a test nozzle are reported. Particles of a known diameter in the range from 0.5 to 11.3 μm were accelerated under various flow conditions. Particle velocities were measured near the nozzle exit. The measurements demonstrated the feasibility of determining particle size from particle velocity.

Theoretical studies of the test nozzle showed that it was possible to accurately calculate the particle velocities. Additional theoretical investigations showed that aerodynamic diameter can be determined from particle velocity if the particle motion is not too ultra-Stokesian. A nozzle configuration and flow rate are proposed for the measurement of the aerodynamic diameter of atmospheric aerosol in the range from 0.5 to 10 μm.

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^☆: Particle Technology Laboratory Publication No. 392.

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Aerodynamic particle size measurement by laser-doppler velocimetry☆

Abstract

Particle size measurement by Doppler-shifted laser light - a test of Stokes-Einstein relation

J. appl. Phys.

Generation of monodisperse aerosol standards

Envir. Sci. Tech.

Measurement of the size distribution of liquid and solid aerosols by Doppler shift spectroscopy

J. Colloid Interface Sci.

Aerosol beam spectrometry

Nature

The Mechanics of Aerosols

Aerosol measurement by laser-Doppler spectroscopy

J. Aerosol Sci.

Deposition and retention models for internal dosimetry of human respiratory tract

Hlth Phys.