Abstract
In this study, the effects of aerosol dynamics on the aerosol optical properties were analytically investigated using an approximated expression for the overall extinction coefficient (bext), which was valid for a wide range of particle size. The processes of both coagulation and condensation in the continuum region were considered using the moment method, with an overall extinction coefficient obtained from the harmonic mean between the overall particle extinction coefficient of the Rayleigh scattering and geometric scattering regions. The derived analytical expressions were compared with the asymptotic expressions of the extinction coefficient, which showed that the obtained expressions ultimately approached the asymptotic expressions. Subsequently, this study showed a simple and straightforward method for estimating the changes in the extinction coefficient and visibility of polydispersed aerosols during aerosol dynamic processes. The accuracy of the approximated overall coefficient was dependent on a given aerosol refractive index and size parameter. Usually, the error was less than 8% for an average size parameter range of 0-80.
| Original language | English |
|---|---|
| Pages (from-to) | 904-916 |
| Number of pages | 13 |
| Journal | Journal of Aerosol Science |
| Volume | 39 |
| Issue number | 10 |
| DOIs | |
| State | Published - Oct 2008 |
Bibliographical note
Funding Information:This study was supported by the National Research Laboratory (NRL) Program (no. R0A-2006-000-10221-0) funded by Korea Science and Engineering Foundation (KOSEF). C. H. Jung was supported by 2007 academic funds of Kyungin Women's College.
Keywords
- Analytic expression
- Asymptotic expression
- Coagulation
- Condensation
- Continuum region
- Extinction coefficient