Simulação computacional e comparação experimental de uma bolha de ar em uma coluna de água

Abstract

In off-shore petroleum industry, after separation of the petroleum-gas-water mixture, the water from this separation must pass through a flotation process, in a way that allows the water to return to the maritime environment in adequate purity conditions. The present essay has the purpose of developing a method of numerical analysis of the gas bubble rise in water, to obtain correlations that assist in the flotation process understanding. The characteristic equations will be solved using the software ANSYS/FLUENT, which uses finite volume solving method. For the gas-liquid interface, the Volume of Fluid (VOF) method will be used to model the hydrodynamical interaction state. A parameter variation analysis was performed in order to understand and study the best combination of factors for the multiphase simulation of bubble rise in water. The simulation results were compared to each other, according to the different parameters from simulations, besides the comparison to experimental data obtained in NUEM laboratory. It is concluded that the use of small time steps generates data that cannot be seen in the experiments, due to the differences between the time-steps of image capture, besides evaluating that the Level-Set function brings calculation inconsistences, summing errors during the simulation.