Dourado H., Santos J., Reis Jr N., Melo A., 2012, The Effects of Atmospheric Turbulence on Peak-to-Mean Concentration Ratio and its Consequence on the Odour Impact Assessment Using Dispersion Models, Chemical Engineering Transactions, 30, 163-168.
The present work evaluates the use of two regulatory atmospheric dispersion models (AERMOD and CALPUFF) and two CFD models (LES-Dynamic Smagorinsky and LES-Wale) to assess odour impact. Average concentration results are compared with experimental wind tunnel (WT) data. P/M concentration ratio results estimated from the regulatory models through a power law scaling factor are compared with the P/M concentration predicted by LES results. CFD/LES results showed good agreement when compared to wind tunnel results, both for the mean and fluctuating flow and concentration patterns. AERMOD and CALPUFF underestimated the highest concentration levels when compared to CFD/LES results and WT measurements. Peak to mean (P/M) concentration ratio estimated by the regulatory models through the use of a power law relating the P/M concentration ratio to short-to-large-term averaging time ratio were underestimated when compared to CFD/LES observed P/M. Results indicate CFD/LES can be a viable tool for studying fluid flow characteristics that affect odour impact assessment.