Accession Number : AD0777502

Title :   Freezing Water with Sized AgI Particles. III: Experimental Procedure, Results, and Conclusions.

Descriptive Note : Research and development technical rept.,


Personal Author(s) : Gerber,Hermann E.

Report Date : MAR 1974

Pagination or Media Count : 72

Abstract : The experimental objective of this study is to determine the relationship between the sizes of thermal AgI particles and the particles' ability to activate ice by freezing. That relationship is essential to determine the efficiency of the generator output, which in turn is required for a reasonable guess of the outcome of cloud seeding experiments. The following sections of this paper describe in detail the experimental design of the particle size-activity measurements. Included are the techniques to generate uncoagulated thermal AgI particles, to collect the particles as a function of their size on the collecting foil of the Goetz Aerosol Spectrometer, to activate the particles on the foil in the cold chamber which properly simulates the freezing mechanism of ice nucleation, and to record the nucleation events as a function of activation time and temperature. The experimental results are compared to the theoretical predictions.

Descriptors :   *Silver iodide, *Freezing, *Cloud seeding, *Particle size, Aerosols, Ice, Data processing, Condensation nuclei, Calibration, Theory

Subject Categories : Atmospheric Physics
      Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE