air pollution, air dispersion modelling, wind tunnel, human health
Air pollution has been a pressing issue since the last few decades thus, the study of pollutant dispersion using wind tunnel is significant. This paper provides a comprehensive investigation into air pollution and its effects on human health, and strategies for their control and monitoring. A detailed analysis of air dispersion modeling, atmospheric boundary layer, wind gradient, Gaussian plume dispersion modelling, and the influential factors like stack height, wind velocity, meteorological parameters and presence of canyons affecting pollutant dispersion is done. It is found that increasing the stack height, building step-up canyon configuration, increasing wind velocity to a critical level would result in greater pollutant dispersion and lower downwash to receptors. Additionally, the effect of temperature, turbulence, humidity on the pollutant dispersion and the height of boundary layer.
The research further extends into how wind tunnels play a significant role in environmental studies. It thoroughly examines the fundamental concepts and applications of different types of wind tunnels, that includes subsonic, transonic, supersonic, and hypersonic wind tunnels. Furthermore, the paper describes design components of environmental subsonic wind tunnels which can be categorized into closed-circuit and open-circuit wind tunnel. It further describes how to optimize wind tunnel designs by assessing pressure losses and the power requirement. Further, the report focuses on how laminar and turbulent wind flow rates affect the formation of wake and the lift , drag forces. It was concluded that at adverse pressure gradient, boundary layer separation occurs that enhances the drag coefficient. To determine the total force acting on an object in wind tunnel, pitot tubes are used to measure static and total pressure at different points along the wind flow across the object to determine the pressure distribution coefficient which in accordance with Bernoulli’s equation for conservation of mass and continuity equation calculates the lift and drag coefficients at varying Reynold’s number (turbulence). Additionally, a comparative evaluation between computational fluid dynamics and wind tunnels is presented, describing their distinct roles and applications in environmental research. The results showed wind tunnel is still important to validate the results of CFD modelling.
Faculty of Applied Science & Technology (FAST)
© Ridhima, Gia My Nguyen
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Original Publication Citation
Nguyen, G.& Ridhima, R. (2023). Air dispersion modelling and wind tunnel [Unpublished]. Faculty of Applied Science & Technology, Sheridan College.
Ridhima, Ridhima and Nguyen, Gia My, "Air Dispersion Modelling and Wind Tunnel" (2023). Featured Student Work. 4.