Application of Detached Eddy Simulation to neighbourhood scale gases atmospheric dispersion modelling

• Published in: Journal of hazardous materials Vol. 261; pp. 653 - 668
• Main Authors: Kakosimos, K.E., Assael, M.J.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.10.2013; Elsevier
• Subjects: Air Movements; Air Pollutants; Applied sciences; Chemical engineering; Cities; Detached eddy; Exact sciences and technology; Gas dispersion; Gases; Models, Theoretical; Neighbourhood scale; Pollution; Risk assessment; Safety; Spalart–Almaras; Urban scale; Neighbourhood scale; Detached eddy; Spalart–Almaras; Risk assessment; Gas dispersion; Urban scale; Buildings; Urban area; Risk analysis; Modeling; Spalart―Almaras; Large eddy simulation; Complex terrain; Atmospheric dispersion
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2013.08.018

•A model for the simulation of gases dispersion in urban terrain based on DES-SA.•Successful evaluation of the model according to well-established case studies.•Integration of the model with a new and custom mesh-generation algorithm.•The new model puts forward the possibility of DES to be used in this field as a better alternative of LES and RANS. This paper addresses the current important problem of modelling the dispersion of toxic gases released in the urban terrains (i.e. neighbourhood scale) by the Detached Eddy Simulation (DES). This approach is a resolution that lays between the Reynolds Averaged Navier–Stokes and Large Eddy Simulation models and focuses especially on establishing a better balance between efficiency and accuracy. Herein are presented the theoretical approach of a new model, which is based on the DES and the Spalart–Almaras turbulent closure and a number of validation tests like the flow and the dispersion over and around a single building and an array of buildings. Overall, employed validation metrics were within the acceptable limits and the model demonstrated an acceptable agreement with the experimental datasets which confirms the use of this approach for the modelling and dispersion of gases in complex terrains like a city.