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This work presents a non-steady state and three-dimensional mathematical modeling to predict moisture transport (based on the Langmuir-Type Model) inside the vegetable fiber-reinforced composite materials. The numerical solutions of the governing equations have been obtain using the finite-volume method. The model was apply for vegetable fiber-reinforced polymer composites. Emphasis to the geometrical dimension effect of the composite in the water absorption process was given. Results of the average moisture content, free and entrapped water molecules concentration kinetics and free and entrapped water molecules concentration distributions inside the material along the process are shown and analyzed. In the distributions of the analyzed properties, it was observed that the geometric dimensions of the composite has influence in the water absorption process.

In the scenery of the oil industry, the remaining resources associated with light oils have an increasingly smaller share in the natural energy resources available to man, and in return the importance of resources associated with heavy oils has increased significantly. One of the drawbacks of this type of oil is associated with its low mobility due to the high viscosity in reservoir conditions, making the transport in pipelines very difficult, especially through pumping methods that require high powers. Thus, the development of new techniques and optimization of some existing technologies, aiming at the commercial use of heavy oil accumulations plays an important role. A viable technique that has been used is the core annular flow, in which small amounts of water are injected close to the pipe wall, lubricating the oil core, reducing friction and decreasing the pressure drop during the flow. In this sense, this work aims to perform, numerically, an energetic and hydrodynamic analysis of a heavy oil-water two-phase flow, using the core-flow technique, in curved pipes, in the Ansys CFX software. Results of the velocity, pressure, and volume fraction distribution of the involved phases are presented and analyzed. It was observed that the proposed mathematical model was able to accurately represent the analyzed phenomena and that a reduction factor in the pressure drop of 28.4 was obtained as compared to the heavy oil single-phase flow.

Hidrociclones são equipamentos usados em processos de separação óleo-água. São considerados eficientes, compactos, seguros, de simples construção e manutenção, e baixo custo, quando comparados a outros equipamentos de semelhante aplicação. Diante disso, este trabalho tem como objetivo analisar numericamente o processo de separação da mistura óleo-água em um hidrociclone, quanto ao seu aspecto fluidodinâmico. Para a solução numérica das equações governantes utilizou-se o software Ansys CFX. Resultados dos campos de pressão e fração volumétrica da fase óleo, e do desempenho de separação do equipamento são apresentados e analisados. Dos resultados obtidos verificou-se que as maiores pressões ocorrem próximo as paredes e entrada do equipamento, que as maiores frações volumétricas do óleo ocorrem na região central e próximo a saída do hidrociclone, e que este equipamento apresentou uma eficiência de separação superior a 99,8%.