Summary
Out information from the limited amount of observations about the capture of airborne particles by cloud and precipitation drops reveals that this complex scavenging phenomenon depends on various, the dropletparticle collisions simultaneously driving micromechanisms. Theoretical models attempt to treat these processes in combination.
A major task of the study reported here was to describe the responsible scavenging interactions as part of a microdynamical simulation model for particle and drop size spectra. Using for this purpose the theory of nonlinear stochastic collisions we show that key properties (such as size dependence, relaxation, etc.) associated with particle scavenging are predicted satisfactorily with meteorologically representative input data.
Zusammenfassung
Die aus Beobachtungen gewinnbare Information über das Einfangen von luftgetragenen Teilchen durch Wolken- und Niederschlagstropfen zeigt klar, daß dieses komplexe Auswaschphänomen von mehreren, gemeinsam für die Tropfen-Teilchenkoflisionen verantwortlichen Mikromechanismen abhängt. In theoretischen Modellen versucht man, diese Prozesse kombiniert zu behandeln.
Kernpunkt der theoretischen Untersuchungen, die hier vorgestellt werden, war es, die verantwortlichen Wechselwirkungen in einem mikrodynamischen Simulationsmodell für Größenspektren von Teilchen und Tropfen zu beschreiben. Hierfür wurde die entsprechende Theorie nichtlinearer stochastischer Kollisionen verwendet. Die Rechnungen liefern, daß wichtige Eigenschaften (wie Größenabhängigkeit, Relaxation usw.), die mit dem Teilchenauswaschvorgang zusammenhängen, bei Annahme meteorologisch repräsentativer Eingabedaten zufriedenstellend bestimmt werden können.
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Herbert, F., Beheng, K.D. Scavenging of airborne particles by collision with water drops —model studies on the combined effect of essential microdynamic mechanisms. Meteorl. Atmos. Phys. 35, 201–211 (1986). https://doi.org/10.1007/BF01041812
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DOI: https://doi.org/10.1007/BF01041812