Flow Morphologies in Straight and Bent Horizontal Pipes

Abstract

Two-phase flows in pipes develop characteristic patterns or flow morphologies. Their transport between process units and plant components often involves short pipes, large pipe diameters, as well as bends and curvatures. The prediction of the predominantly undeveloped flow morphologies in such systems is challenging and subject to high uncertainties due to lacking experimental data and universal engineering models. In this work, comprehensive experimental studies were conducted in horizontal straight and bent pipes of 50 mm and 200 mm diameter. Wire-mesh sensors were applied at characteristic positions to obtain the gas–liquid distributions with high spatiotemporal resolution. Subsequently, a fuzzy classification method is applied to assign a flow pattern to characterize the flow conditions. As this assignment is fuzzy, we introduce an advanced concept of a color-coded flow map visualization for further analyses. As a result, we analyze the effect of pipe curvatures on the flow morphology and its downstream recovery.