Techniques for the Determination of Particle Growth Factors in Real Time

Abstract

A technique developed by Snider and Petters in 2008 is used to determine hygroscopic growth factors of aerosol particles. Simultaneous measurements from two optical particle-size spectrometers are used, where one measures the particles in the ambient atmosphere, and the other after drying them out. From 826 July 2019, aerosol data was collected west of Boca Chica Airfield, Florida. The Naval Postgraduate Schools Aviation Facility Twin Otter aircraft, equipped with a forward scattering spectrometer probe (FSSP), passive cavity aerosol spectrometer probe (PCASP), and an aerosol and precipitation spectrometer (CAPS) was used to measure dry and ambient aerosol particles. Comparisons of particle diameters at different ambient relative humidities (RH) were used to estimate the aerosol growth factors (GF). In general, the calculated GF increased as RH increased. GF values obtained varied wildly and ranged from 0.2 to 12.5 between 27 and 95 percent RH, but averaged into 5 percent RH ranges, they ranged from 2.0 to 5.5. Using wind direction as an indication of the source of the aerosol suggests some of the variability may be attributed to the aerosol composition.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 2020
Accession Number
AD1114599

Entities

People

  • Coriandre T. Johnson

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Accuracy
  • Aircrafts
  • Atmospheric Attenuation
  • Chemistry
  • Electromagnetic Radiation
  • Forward Scattering
  • Growth Factors
  • High Energy Lasers
  • Laser Beams
  • Lasers
  • Light Scattering
  • Light Sources
  • Materials
  • Measurement
  • Optical Properties
  • Particle Size
  • Refractive Index
  • Scattering
  • Thermodynamic Properties
  • United States

Fields of Study

  • Environmental science

Readers

  • Aerosol Science/Aerosol Physics
  • Criminal Law