Reconciling Gaussian plume and Computational Fluid Dynamics models of particulate dispersion

Joseph, G. M. D.; Hargreaves, D.M.; Lowndes, I. S.

Abstract

Computational Fluid Dynamics (CFD) is increasingly used to model particulate dispersion in situations where Gaussian Dispersion models are inappropriate or inaccurate. However, there is evidence which indicates that many CFD models under-predict lateral plume spread. This paper aims to address this by imple- menting a strategy which incorporates wind direction variability into CFD models using a formulation which is also used in the UK-ADMS plume spread module. In the present work, a series of CFD simulations are run at various wind angles. The outputs from these simulations are weighted using a Gaussian probability density function and combined to produce a plume. The standard k−ε model has been employed to solve the RANS equations of the flow field for stable, neutral and unstable atmospheric stabilities, coupled with the Lagrangian Particle tracking model to model dispersion. By comparing the CFD accretion profiles to UK-ADMS dry deposition results, it is observed that the proposed modelling methodology produces lateral spreading of the plume which is comparable to that obtained using UK-ADMS. However, the Lagrangian integral time scale constant, c L , which governs the influence turbulence has on the dispersion, must also be modified to bring absolute values of accretion rates in line with those observed in UK-ADMS.

Citation

Joseph, G. M. D., Hargreaves, D., & Lowndes, I. S. (2020). Reconciling Gaussian plume and Computational Fluid Dynamics models of particulate dispersion. Atmospheric Environment: X, 5, Article 100064. https://doi.org/10.1016/j.aeaoa.2020.100064

• Journal Article Type: Article
• Acceptance Date: Jan 18, 2020
• Online Publication Date: Feb 6, 2020
• Publication Date: 2020-01
• Deposit Date: Jan 22, 2020
• Publicly Available Date: Feb 19, 2020
• Journal: Atmospheric Environment: X
• Print ISSN: 2590-1621
• Electronic ISSN: 1352-2310
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 5
• Article Number: 100064
• DOI: https://doi.org/10.1016/j.aeaoa.2020.100064
• Keywords: dispersion; CFD; Gaussian Plume; particulates
• Public URL: https://nottingham-repository.worktribe.com/output/3780724
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S2590162120300034
• Additional Information: This article is maintained by: Elsevier; Article Title: Reconciling Gaussian plume and Computational Fluid Dynamics models of particulate dispersion; Journal Title: Atmospheric Environment: X; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.aeaoa.2020.100064; Content Type: article; Copyright: © 2020 Published by Elsevier Ltd.