Aerosol Aspiration Efficiency of Blunt and Thin-Walled Samplers at Different Wind Orientations

The measured aerosol aspiration efficiency of a thin-walled probe and 5 blunt (thick-walled) samplers was used to compare the aspiration efficiency calculated using the models developed by Belyaev and Levin (1972, 1974) and by Vincent and his colleague (1987, 1995). At 0° wind direction, the model developed by Belyaev and Levin agrees quite well with the experimental value for both the thin-walled probe and the blunt samplers. In this case, the blunt sampler body diameter ( D b ) was used to replace the inlet diameter ( D i ) for the calculation of the Stokes number (St). At 90° and 180° wind directions, the model developed by Vincent and his colleague agrees fairly well with the experimental value. This study shows that the model developed by Belyaev and Levin, at 0° wind direction, can be modified to calculate the aerosol aspiration efficiency by using personal samplers as area samplers. For the model developed by Vincent and his colleague, in addition to personal sampler application, at 90° and 180° wind directions their model can also be used to estimate the aspiration efficiency of area samplers.