AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Towards Accurate Calculation of Particle Size Distributions from Fast-SMPS Measurements
ISHARA JAYASURIYA, Meilu He, Suresh Dhaniyala, Clarkson University
Abstract Number: 363 Working Group: Instrumentation and Methods
Abstract The Scanning Mobility Particle Sizer (SMPS) is one of the most popular instruments for aerosol experimental research. The SMPS enables measurements at very high resolution and accuracy and over a reasonably broad size range. While the SMPS can theoretically provide size measurements with an uncertainty of ~1%, such accuracies are difficult to obtain during practical operation. In particular, when the SMPS is operated over a finite scan-time, the non-idealities in the behavior of the scanning-DMA, the response of the CPC, and the transport of particles between the DMA and the CPC must be accurately accounted for. While several theoretical approaches for the above identified non-idealities have been proposed, the practical deployment of these approaches requires experimental identification of critical system parameters. In this study, the response of a fast scan SMPS system is modeled to understand the importance of different system parameters on the instrument performance, and experimental approaches to obtain the necessary system parameters are established. The system modeling approach and related experiments will be discussed and the implications for accurate sizing of ultrafine particles with fast scanning will be detailed.