The diffusion charging sensor (DC), photoelectric aerosol sensor (PAS) and condensation particle counter (CPC) are real-time particle instruments that have time resolutions <10s and are suitable for field use. This paper shows how the relative fraction of nuclei mode particles (D≤50nm) in ambient combustion aerosols can be determined, along with the coverage degree of the respective accumulation mode particles with a modal diameter of ∼100nm. Main tools for interpretation are the diameter of average surface DAve,S (obtained from CPC and DC measurements) and PAS/DC versus DAve,S scatter plots. Compared to the scanning mobility particle sizer (SMPS), which is a standard instrument for aerosol particle size distribution measurements, the presented method has a limited accuracy, but is substantially faster. Additionally, it is experimentally less demanding than SMPS measurements, especially for field applications.
Bibliographical noteFunding Information:
Funding support for the mentioned CRC E-43 project is sponsored by the following US Institutions: Coordinating Research Council (CRC), Department of Energy/National Renewable Energy Laboratory (DOE/NREL). Co-sponsors are the Engine Manufacturers Association, Southcoast Air Quality Management District, California Air Resources Board, Cummins Inc., Caterpillar Inc. and Volvo Inc.
- Diesel exhaust
- Diffusion charging
- Urban aerosol