UNCLASSIFIED
The Green continuous-action cloud chamber has been placed in
operation and calibrated.
It was found suitable for measuring aerosol
pares concentrations, regardless of particle size or size distribution,
in the approximate range of 5 X 10+
particles/cc to 2 X 10° particles/cc,
with an accuracy of 5.2% standard deviation when a total of 200 particles
is counted.
ORNL - 1656
~-
ELECTROSTATIC PRECIPITATOR FOR MEASURING PARTICLE-SIZE
DISTRIBUTION IN AEROSOLS.
Bernard G. Saunders and R. L. Quinn, 8 February 1954.
'
UNC LASSIF IED
(U)
This report summarizes the work accomplished in developing an
electrostatic precipitator for the determination of particle-size dis-
under a microscope in order to determine, the size distribution.
The object
of this project was to develop an instrument that would operate semi-
automatically by indicating the particle distribution electrically.
The
scheme was to collect the charge-bearing particles on a series of
collector plates.
Particles of each size range would fall on @ particular
plate and impart charges at a measurable rate.
Thus, a comparison of the
beam currents would give the size vs number distribution.
A precipitator designed to meet this objective has been partially
built and tested.
Laminar flow of the smoke in the system was obtained.
Under a given condition of laminar flow, the smoke stream can be seen to
bend in an are and diverge like a spectrum, as anticipated.
It was hoped
that the performance of the precipitator could be checked by measuring
the diameters of the particles collected in various locations.
Samples
were collectec on the plates for a variety of operating conditions.
Electron
photo-micrographs were made of the particles.
At this reporting, none has
been obtained which is sharp enough to permit measurement.
Before further
progress can te made, the problem of obtaining satisfactory micrographs
must be studied.
ORNL - 1657
-
ROTATING PRISM FOR USE WITH CLOUD CHAMBERS.
Bernard G. Saunders, 15 February 1954.
UNCLASSIFIED
~(U)
The use of a rotating prism is indicated when one wishes to
-observe moving cloud-chamber droplets and to measure their velocities.
UNCLASSIFIED
WNRO
ee
ae pe eee
Devices of this sort have been constructed by other laboratories.
Their operation depends on the Cepositing of particles by electrostatic
means along a plate at distances corresponding to the particle size.
Such
devices have heretofore required that the deposited particles be counted
ee
tribution in smokes.
: