Estudo da transferência de massa de poluente no topo de um dossel urbano

• Ano de defesa: 2015
• Autor(a) principal: Cezana, Fernanda Capucho
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Doutorado em Engenharia Ambiental; Centro Tecnológico; UFES; Programa de Pós-Graduação em Engenharia Ambiental
• Palavras-chave em Português: Mass exchange; Transfer velocity; Urban canopy; Buildings with different heights; Simulação numérica; Simulação das grandes escalas (LES); Transferência de massa; Velocidade de transferência; Prédios de diferentes alturas; Dossel urbano; Massa - Transferência - Velocidade; Poluentes; Edifícios; Engenharia sanitária; 628
• Link de acesso: http://repositorio.ufes.br/handle/10/10326

The objective of this work was to investigate the mass exchange process through the top of the urban canopyby two methodologies, i.e, direct numerical simulation (DNS) and large-eddy simulation(LES).Three different configurations were usedtoobtaining the DNS data: two over a regular aligned array and one over a staggeredarray. The winddirections for the simulations over the regular array were 45º and 0º. The third simulation has a 45º forcing direction to a staggered array. In all cases buildings havethe same height and the scalar source is located withinthe urban canopy. For thealignedarray and 0º forcing direction the scalar source above the canopy was usedas well.LESsimulation was performed over astaggered array of buildings with different heights andwith different source locations. It was found that for a more realistic array of buildings (buildings with different heights)the flow and dispersion of pollutants become more complexthan they are in the case of buildings with uniform heights.It wasconclude that thevertical scalar transfer through a surface located at a meanheight ofthe obstacles is influenced by both effects turbulent and advective, whereas the turbulent component dominatesthe verticalflux throughthe top of thearray of buildings with uniform heights. Thus, the parameterization of the transfer velocity on the top of the urban canopy will be strongly influenced by different transfer process occurring on it, depending on the configuration used.