Miniature Condensation Particle Counter

The concentration and size of atmospheric particles are critical parameters to evaluating the dynamics of aerosol processes, and to understanding aerosol cloud interactions . Especially important are highly time-resolved measurements aloft, for this is our only direct glimpse into the three-dimensional profile of atmospheric aerosols. In the past these vertical profiles were obtained with aircraft capable of large payloads. Now, much smaller platforms and unmanned aerial vehicles are used. Continued three-dimensional mapping of atmospheric aerosols requires correspondingly smaller instrumentation than now available. We propose a miniature electrical mobility sizing system that uses a new approach to provide instantaneous 1-2Hz) snapshots of the ambient aerosol size distribution in the 10nm to 500nm size range. Our approach builds on our experience with the parallel plate mobility separator of Brookhaven’s Fast Imaging Mobility Spectrometer, but uses a different approach to image the particles, so as to provide the same capability in 10- to 20-fold smaller package. Our new approach relies on a new type of focusing and condensational growth cell. This component will be designed, fabricated and tested in our Phase I project. We will examine the accuracy and precision of the new approach through calibration studies with mono- dispersed particles. Additionally, we will explore an innovative means to further shrink the size of the critical mobility size selection component. Commercial applications span a wide range of industrial and laboratory research uses for which rapid measurements of aerosol size distributions are needed. It could potentially replace many scanning mobility particle sizing systems, which have become standard aerosol equipment in laboratories and industry.