"A technique is investigated for counting water droplets formed in a vertical plate steady flow thermal diffusion chamber designed to count cloud condensation nuclei. The counting technique utilizes light scattering. The light source is a He-Ne laser. The detector is a photomultiplier tube. The technique differs from that used in instruments manufactured by Bausch and Lomb, Royco, Climet, etc., in that the aerosol is not passed through a capillary tube. Instead, the viewed volume is optically defined.
It was found that in the configuration tested, the viewed volume is not well enough defined for use with polydisperse aerosols, although the apparatus as tested is useful for sizing and counting monodisperse aerosols. The investigation also indicates that the most likely way to improve the performance would be to use a thin rectangular slit as an optical stop, rather than the circular aperture tested"--Abstract, page ii.
Alofs, Darryl J.
Stampfer, J. F.
Mechanical and Aerospace Engineering
M.S. in Aerospace Engineering
National Science Foundation (U.S.). Atmospheric Sciences Section
University of Missouri--Rolla
vi, 36 pages
© 1973 Duane Burton Bush, All rights reserved.
Thesis - Open Access
Optical detectors -- Design
Atmospheric nucleation -- Measurement -- Instruments
Print OCLC #
Electronic OCLC #
Link to Catalog Record
Bush, Duane Burton, "An optical detector of water droplets within a thermal diffusion chamber" (1973). Masters Theses. 3367.