Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Numerical simulation of flow and pollutant dispersion in an urban intersection using k-ϵ turbulence model
Submission Author:
Tomaz Antônio Lisboa e Silva , SP
Co-Authors:
Tomaz Antônio Lisboa e Silva, Fernanda Capucho Cezana
Presenter: Tomaz Antônio Lisboa e Silva
doi://10.26678/ABCM.COBEM2023.COB2023-1476
Abstract
The dispersion of pollutants in urban intersections is a complex problem that can be influenced by a series of factors, such as building geometry, wind direction and speed, traffic density, and the location of pollution sources. Traffic density can significantly affect pollutant dispersion, and it is directly affected by the number of cars present in an urban area. This factor is important to understanding how to reduce pollutant concentrations. In this paper, the finite volume method together with a non-structured polyhedral mesh was used, in which it solved the mass, momentum and chemical species conservation equations, using the Ansys Fluent© 23.0 computational code. Combined with the k-ϵ turbulence closure model, which is one of the most widely used models for analyzing pollutant dispersion in urban areas. The method's validation was carried out using the DAPPLE model-based boundary conditions, and the initial model comparisons and velocity profiles (without incorporating cars). This step was crucial to ensure the necessary reliability and relevance of both the quantitative and qualitative results. Following the successful validation of the method, the study proceeded to examine the impact of cars on the flow and dispersion of carbon monoxide at the intersection. This study utilizes a numerical simulation with a low computational cost, along with a high-performance mesh, and provides data for future research in the area, which can aid in making informed decisions about implementing pollution control measures. These measures may include adjusting traffic light timing and restricting vehicle traffic during peak hours. Furthermore, it is worth mentioning that this topic has a direct impact on the lives of people who live and work near these areas. Exposure to high levels of air pollution can lead to respiratory, cardiovascular, and neurological problems, among others. Therefore, it is crucial to improve the air quality of cities. To achieve this goal, the use of numerical approaches, such as computational fluid mechanics studies (for example, Reynolds-Averaged Navier-Stokes methods), is a valuable tool to aid urban planners make informed decisions on how to reduce air pollution in urban areas and protect public health.
Keywords
Pollutant dispersion, Urban intersection, RANS, Computational Fluid Dynamics
