AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Simulation of SOA Formation Using Gas-Wall Process Free Model parameters in the Presence of Inorganic Salts Containing Electrolytes under Various NOx Levels
SANGHEE HAN, Myoseon Jang, University of Florida
Abstract Number: 666 Working Group: Aerosol Chemistry
Abstract The Gas-Wall Process (GWP) is known to large impact on the prediction of Secondary Organic Aerosol (SOA) yields due to the bias of the semiempirical model parameters obtained from the chamber studies. Recently, our research team launches the GWP model using the Quantitative Structure Activity Relationship (QSAR) to predict the impact of chemical structure on GWP under the various humidity conditions. Our laboratory’s research efforts have also improved the state-of-the science-art via the development of the UNIfied Partitioning-Aerosol phase Reaction model (UNIPAR), which features partitioning in multiphase and emerging chemistry in the aerosol phase. However, the model parameter in the preexisting UNIPAR inherits the impact of GWP due to the GWP biased chamber data. In this study, the GWP model integrated with QSAR is applied to the UNIPAR model to improve the model parameters. The resulting model parameters are applied to various SOA systems that are produced via the photooxidation of different hydrocarbons under varying NOx, inorganic seed aerosol, and humidity conditions. The impact of GWP on SOA formation is also evaluated by comparing the predicted SOA mass using the model parameters without GWP and that using the model parameters inheriting GWP. The characteristic time analysis of various processes including partitioning, gas-phase reactions, and aerosol phase reactions suggests that the impact of GWP on SOA formation is relatively small in the presence of the inorganic seeds compared to that without aqueous reactions.