Initial Size Distributions of Aerosols

The use of digital computer programs to determine the size distribution of an aerosol as a function of time requires knowledge of the initial size distribution. This paper presents the results of an analytical investigation made to determine whether an aerosol produced as an instantaneous source approaches a self-preserving shape. For high number density aerosols, calculations indicate that the initial size distribution rapidly approaches a self-preserving shape which can be represented by a log-normal distribution with a standard geometric deviation between 1.34 and 1.40. This log-normal distribution is utilized to calculate a pseudo-initial particle size distribution for use as the initial condition in digital computer programs.