Sampling charged particles with cascade impactors. Final report, April 1977-September 1978

Technical Report · Mon Jan 01 04:00:00 EST 1979

OSTI ID:5643645

Farthing, W E; Hussey, D H; Smith, W B; Wilson, Jr, R R

The report discusses three sets of experiments which demonstrate that a cascade impactor sampling a charged aerosol may yield a particle size distribution measurement that deviates from the time distribution. The distributions indicated more large particles and fewer small particles than actually existed, due to the particles' attraction to the grounded impactor plates (stages). Although higher charge levels produced larger deviations from the true size distribution, the magnitude of the deviation and the corresponding correction factor for any given charged aerosol are unpredictable. Also, the error was smaller if glass fiber substrates were used as collection surfaces instead of bare metal. For electrostatic precipitators operating at normal charging conditions (an electric field of 400,000 V/m and a current density of 0.0003 A/sq m/s), the size distribution (measured by the lower stages of an Andersaen cascade impactor with glass fiber substrates) was not significantly different from the true size distribution.

• Research Organization: Southern Research Inst., Birmingham, AL (USA)
• OSTI ID: 5643645
• Report Number(s): PB-290897
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AEROSOLS
AIR POLLUTION CONTROL
CASCADE IMPACTORS
COLLOIDS
DESIGN
DISPERSIONS
DISTRIBUTION
ELECTROSTATIC PRECIPITATORS
EQUIPMENT
LABORATORY EQUIPMENT
PARTICLE SIZE
PERFORMANCE TESTING
POLLUTION CONTROL
POLLUTION CONTROL EQUIPMENT
SAMPLING
SIZE
SOLS
SPATIAL DISTRIBUTION
TESTING