Grantee Research Project Results
2013 Progress Report: A compact, low-cost, network accessible, optical particle counter for the real time measurement of submicron aerosol particle size distributions
EPA Grant Number: R835139Title: A compact, low-cost, network accessible, optical particle counter for the real time measurement of submicron aerosol particle size distributions
Investigators: Bertram, Timothy H
Institution: University of California - San Diego
EPA Project Officer: Chung, Serena
Project Period: February 1, 2012 through January 31, 2015
Project Period Covered by this Report: February 1, 2013 through January 31,2014
Project Amount: $250,000
RFA: Developing the Next Generation of Air Quality Measurement Technology (2011) RFA Text | Recipients Lists
Research Category: Early Career Awards , Air Quality and Air Toxics , Air
Objective:
The objective of this proposal is the development of a miniature, wireless optical particle counter (OPC) capable of measuring and transmitting submicron aerosol particle number and size distributions to a remote server in real-time. The proposal aims to provide the framework for significant improvements in the spatial and temporal resolution of continuous aerosol particle measurements on the city scale, while dramatically improving the availability of these data in real time.
Progress Summary:
Year 2 work has focused on the continued development and characterization of the blue diode optical particle counter. We are now working on Version 2 of the blue diode OPC. The redesign of the cavity was done to: 1) increase the solid angle of light scattered in the forward direction from particles in the beam path, and 2) replace the low sensitivity PIN diode with a high sensitivity PMT. This has resulted in a slightly larger optical cavity than V1 20cm in length. The new optical design is coupled with a new set of laser diode drivers that are more stable than V1, ultimately permitting detection of smaller peak heights that are associated with particles of diameter closer to 200 nm. We have broadened our efforts in this specific area to properly constrain the error associated with optical detection of ambient aerosol, with specific attention to: 1) particle size resolution, 2) impact of particle refractive index on retrieved size distributions, 3) impact of ambient RH, and 4) impact of coincidence counting on total number concentrations.
Journal Articles:
No journal articles submitted with this report: View all 1 publications for this projectRelevant Websites:
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.