AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Evaluation of a Personal Diffusion Battery
DONNA VOSBURGH, Timothy Klein, Maura Sheehan, T. Renee Anthony, Thomas Peters, University of Wisconsin-Whitewater
Abstract Number: 721 Working Group: Instrumentation and Methods
Abstract A four-stage personal diffusion battery (pDB) was constructed to measure submicron particle size distributions. The pDB consisted of a screen-type diffusion battery, solenoid valve system, and electronic controller. A data inversion spreadsheet was created to solve for the number median diameter (NMD), geometric standard deviation (GSD), and particle number concentration of unimodal aerosols using stage number concentrations from the pDB combined with a handheld condensation particle counter (pDB+CPC). The limitations of the pDB+CPC inversion spreadsheet were determined by calculating simulated distributions.
The pDB+CPC with inversion was challenged with propylene torch exhaust and incense exhaust using timings of 80 seconds per measurement cycle and 240 seconds per measurement cycle. The pDB+CPC with inversion measured five of the 12 polydispersed aerosol runs with the acceptable criteria. Three of the runs that did not fall within the acceptable criteria were below the lower limit of the pDB+CPC with inversion. They successfully solved the NMD to 16 nm, a NMD constraint, alerting the operator to the issue. The ratio of the nanoparticle portion of the aerosol (RNano) was calculated for the twelve runs to determine the ability of pDB+CPC with inversion to measure only the nanoparticle portion of the aerosols. The RNano was from 0.87 to 1.01 when the inversion did not solve to a constraint and from 0.06 to 2.01 when the inversion did solve to a constraint. Future work is needed to evaluate the pDB+CPC response to multimodal aerosols.