Simulação do Transporte de Escalares Dentro e Acima de um Dossel Florestal Amazônico

Abstract

The Parallelized Large-Eddy Simulation Model (PALM) was used to better under stand the turbulent exchanges of a passive scalar above and within a forest region located in central Amazonia. A set of simulations were implemented in weak and strong wind conditions, in the development of a diurnal and nocturnal boundary layer, totaling four simulations. A passive scalar source has been introduced into the forest floor. The simulations reproduced the main characteristics of turbulent flow and passive scalar transport between the forest and the atmosphere. Notably, strong and weak wind conditions presented different turbulence structures that led to different scalar exchange patterns both inside and outside the forest. These results show how the passive scalar concentration is influenced by the wind speed at the top of the tree canopy and how the stability conditions influence the efficiency of turbulent transport of scalars in forest regions. Furthermore, higher wind speeds are related to stronger sweep and ejection regimes, generating more intense plumes that are capable of reducing passive scalar concentration within the forest canopy.