This paper presents the results of comparison of experimental and CFD studies of slug flow in a vertical 90° bend using validated models. For the experimental part, Electrical Capacitance Tomography (ECT), Wire Mesh Tomography (WMS), and high-speed videos were used to monitor an air-silicone oil mixture flowing in a vertical 90o bend. The ECT probes were mounted before the bend whilst the WMS was positioned either immediately upstream or immediately downstream of the bend. The downstream pipe was maintained horizontal whilst the upstream pipe was maintained vertical. The bend (R/D = 2.3) was made of transparent acrylic resin. Parallel to the experiments, simulations were carried out for same experiment set-up using the commercial software package Star-CD and Star-CCM+. The condition was simulated with the Volume of Fluid (VOF) model. The simulation predictions were validated against the experimental data. A reasonably good agreement was observed for the results of the experiment and CFD.
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