American Association for Aerosol Research - Abstract Submission

AAAR 38th Annual Conference
October 5 - October 9, 2020

Virtual Conference

Abstract View


Model for Competitive Condensation of Supersaturated Vapor on a Soot Aggregate

ELLA IVANOVA, Alexei Khalizov, Gennady Gor, New Jersey Institute of Technology

     Abstract Number: 118
     Working Group: Carbonaceous Aerosol

Abstract
Atmospheric soot is a major pollutant for the environment. It is the second most significant factor behind global warming, after the greenhouse effect of carbon dioxide. Also, soot has a negative impact on human health. In order to assess these negative impacts of soot on both climate and human health one has to know the microstructure of soot aggregates, which are influenced on their optical properties.

Soot is made of small particles, which are fractal aggregates. However, experiments show that the condensation of vapors on aggregates often causes their restructuring to globules. It was showed that restructuring can be induced by a very small amount of condensate, if the coating material is not distributed uniformly over the aggregate surface of monomers, but located in the gap between them.

In this work, we consider the model for competitive condensation of supersaturated vapor on a soot nanoparticle aggregate: condensation of liquid between monomers or on their surface. Previously, it was shown that it is possible to predict the condensation outcome based on a single dimensionless parameter chi. This parameter chi contains information about the diameter of monomer spheres in the aggregate, the supersaturation of condensing vapor, and also the molar volume and surface tension of the condensate. The main goal of this work to consider different profiles of the condensed liquid between monomers and estimate how does it affect the model for competitive condensation of supersaturated vapor on a soot aggregate. All calculations were numerical. Also, this work is the basis for the process of modeling the restructuring of soot aggregates.