管内の乱流城におけるエアロゾル粒子沈着 －垂直管内の沈着－

抄録

A sampling line used for collecting aerosol particles for dust monitoring generally consists of vertical, horizontal and bent pipes. To estimate the aerosol deposition onto the sampling line as accurately as possible is required for proper evaluation of aerosol concentration. This paper describes the derivation of the reasonable equation of particle deposition velocities onto the vertical pipe wall, where a free flight model by Friedlander et al. and a turbulent particle diffusivity by Lin et al. were used. In particular, a problem concerned with the starting point of free flight of particles is eliminated, and the introduction of Brownian diffusivity for smaller particles and a correction factor to the assumed lag between fluid and particle motions, in the turbulent core of the flowing fluid, for larger particles makes the deposition velocity equation applicable for the whole range of particle size and fluid Reynolds number.