SCALING BEHAVIOR OF PHYSICAL PARAMETERS DESCRIBING AGGLOMERATES

Scaling relations for mass, surface and radius of fractal-like agglomerated particles are derived, and partly corroborated experimentally. Mass corresponds to the number of primary particles forming an agglomerate. The surface measure is the attachment coefficient for neutral molecules or atoms to aerosol particles as measured with the epiphaniometer. The mobility equivalent radius Rz obeys fractal scaling laws under certain conditions. Scaling of the attachment coefficient with mass (or radius) is different in the free molecular regime and the continuum regime. The friction coefficient is proportional to the attachment coefficient, as shown by theory and experiment. © 1990.