Comparison of discrete, discrete-sectional, modal and moment models for aerosol dynamics simulations

Abstract

An open source software (Aerosol and Air Quality Research Lab-Aerosol Dynamics Model, AAQRL-ADM) used for aerosol dynamics simulations is developed by including four models: discrete, discrete-sectional, method of moments, and modal. First, the mathematical description of these models as well as the effects of aerosol dynamics available in the software are reviewed, and a modal model is developed to use multiple modes to represent particle size spectrum. Second, the design of a working principle and user graphical interface (GUI) of AAQRL-ADM is described. Third, the models in AAQRL-ADM are validated by investigating the evolution of particle size distribution (PSD) in considering the effects of coagulation, condensation, and nucleation. Next, the trade-off between simulation accuracy and numerical efficiency is discussed for all of the four models, and a guide to choosing the appropriate aerosol dynamic model in practical simulation is presented. Finally, discrete-sectional, moment, and modal models are used to investigate the particle size distribution in a furnace aerosol reactor along a streamline, coupled with the velocity and temperature profiles. AAQRL-ADM is provided free of charge for the use of public researchers.

Copyright © 2020 American Association for Aerosol Research

EDITOR:

• Nicole Riemer

Acknowledgments

The computing of the discrete and modal models was performed using the facilities of the Washington University Center for High Performance Computing (CHPC), which is partially funded by grant NCRR 1S10RR022984-01A1.

Funding

This work was supported by a grant from the National Science Foundation, SusChEM: Ultrafine Particle Formation in Advanced Low Carbon Combustion Processes; CBET 1705864. H.Z. was supported by the Natural Science Foundation of Beijing [Grant No. 3184051]. High Performance Computing (CHPC) is partially funded by grant NCRR 1S10RR022984-01A1.

Notes

1 As described in the introduction of the discrete model, the total number of discrete size needed in the condensation case is estimated as (100 nm/0.68 nm)³ ∼ 3.2 × 10⁶.