Escoamento anular isotérmico de óleos pesados e água em bifurcações angulares: modelagem e simulação.

Abstract

The oil transport in pipes and connections is dependent on its viscosity and requires much energy for pumping. The Core-Flow technique is gaining prominence due to cost and simplicity on the transportation of heavy oils and ultra viscous. In the present work we studied the transport of heavy oils and ultra viscous steady and using Cartesian coordinates pipe connections or not fitted with 'T' and 'Y'. We evaluated different turbulence models (κ-ε, RNG κ-ε-, κ-ω, SST and SSG Reynolds Stress) together with the mixture model, considering the gravitational effect without chemical reactions occurring during flow properties and physical-chemical constants. We adopted the application Ansys CFX 13 for obtaining results. The results show that the mathematical model showed agreement with the experimental data. By applying the proposed model to a horizontal pipe in there the Core Flow eccentric along the pipeline. The same effect occurs in the main pipe before the fork joints "T" and "Y", obtaining the stratified flow pattern in the early primary and secondary branches and, in some cases, a possible formation of the annular pattern. Among the models evaluated in this study, the SSG turbulence model was the best adapted to the experimental pressure drops. It was observed that there is a reduction in pressure drop with increasing thickness of the annular water. Obtained for the slope of 75 º a pressure drop in the main duct nearest the experimental values. For inclinations of the main and secondary branches, has a pressure drop 6 times the pressure drop of the main duct.