Abstract:
This thesis presents the experimental results of flow pattern in co-current vertical upward gas-liquid flow in narrow rectangular channels. The rectangular test sections (103 mm in length) made of plexi glass have different channel widths of 20, 40, 60 mm and different gap widths of 1, 2 3 mm. The working fluids, used to investigate the effect of viscosity on flow pattern transitions are air-water, air-aqueous glycerol solution 20% (by weight) and air-aqueous glycerol solution 40% (by weight). The comparisons between the experimental data and the predicted data,based on the available model, are also presented. Bubbly, cap-bubbly, slug, churn and annular flow are found in the present experiment. However the bubbly flow is observed only in 40?3 mm rectangular test section with air-water as the working fluid. Considering the effects of various relevant parameters on flow patterns, it is found that as the channel width and gap size increase, at constant liquid superficial velocity, all flow pattern transitions occur at higher gas superficial velocity. As the liquid viscosity increases, bubbly-slug and (cap-bubbly)-slug flow transition occur at lower gas superficial velocity while slug-churn and churn-annular transition occur at higher gas superficial velocity. The shapes of the air-water flow transitions of both predicted and observed have a good agreement.