Simulação numérica tridimensional da evaporação de gotas em meios porosos usando um modelo de escala de poros

• Autor(a) principal: Sartim, Rafael
• Data de Publicação: 2007
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/3890
• topic: Porous media; Droplets evaporation; Pore network models; Meios porosos; Evaporação de gotas; Modelo de escala de poros; Engenharia Sanitária; Materiais porosos; Evaporação; 628

The experimental work and the mathematical modeling of the impact and evaporation of droplets in porous surfaces, are a subject of great interest in innumerable industrial applications as, petroliferous, textile, nourishing, and in inkjet printing technology. Another point of interest would be in environmental applications, as the release of hazardous liquids into the atmosphere during environmental accidents where it is necessary to identify and to quantify the caused environment impact. Experimental results presented by Reis et al. (2003) indicate that the previous approach underestimates the importance of the capillary transport of liquid during the drying process. Thus, one becomes important to develop a model that is capable to incorporate the complete importance of the capillary transport of liquid during the evaporation. In addition, the scale of the problems of evaporation of droplets is very small that questions the applicability of the models that incorporate a macroscopic approach due its representatives of the characteristics of the process. This suggests applications of models that represent the transport of mass in microscopically level, incorporating effect with the random of the porous medium on the vapor transport and liquid during the phase distribution. This work aims at to supply these deficiencies of the current models through the development of a three-dimensional model capable to predict the evaporation of droplets in porous media by means of a model of scale of pores. The assessments of the results is based on the experimental data of Reis et al. (2003) and Reis et al. (2006). As result, the model mainly got good precision in the distribution of liquid phase in the evaporation of the water droplet, while it was behaved in satisfactory way in the prediction of the drying of the droplet of dietyl malonate. About the evaporation rate, its behavior presented certain discrepancy in comparison with the experiments which becomes questionable some considerations about the physical characteristics implementation in the model.