Modelling of the diffusion flame established around multiple droplets

Detalhes bibliográficos
Ano de defesa: 2019
Autor(a) principal: Rafael Pereira Bianchin
Orientador(a): Fernando Fachini Filho
Banca de defesa: Márcio Teixeira de Mendonça, Wladimyr Mattos da Costa Dourado, Fernando Marcelo Pereira
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: eng
Instituição de defesa: Instituto Nacional de Pesquisas Espaciais (INPE)
Programa de Pós-Graduação: Programa de Pós-Graduação do INPE em Combustão e Propulsão
Departamento: Não Informado pela instituição
País: BR
Link de acesso: http://urlib.net/sid.inpe.br/mtc-m16c/2019/01.31.14.03
Resumo: A simplified model for the combustion of multiple droplets is presented under the consideration of unitary Lewis numbers, infinitely fast chemistry and potential flow, and also the assumption that the flame is in the transient region (i.e., sufficiently far from the droplets). The extinction conditions are determined from the Large Activation Energy Asymptotics and studied for several configuration of droplets in axisymmetric geometry. It was found that the critical Damköhler number of extinction decreases monotonically with time, showing that the flame becomes more stable with time. It was also seen that the forced convection makes the flame less stable, but the addition of other droplets does not affect the extinction, which always occur around the largest droplet, unless a smaller droplet is added in the upstream region of a larger droplet, in which case the extinction can occur around the smaller droplet if the convection is sufficiently strong.