Author(s): Detlef Aigner; Hans-B. Horlacher
Linked Author(s): Hans-B. Horlacher
Keywords: Pipeline; Air bubble; Transient flow; Numerical simulation
Abstract: During transient conditions in long-distance pipelines, like pump failure, the internal pressure can drops below atmospheric pressure with the effect of water column separation at geodetic high points. In order to prevent this, high points along the pipeline are usually aerated by air inlet valves. These geodetic high points are shaped in huge bends with large radius of curvature. The air sucked in form big bubbles at the top of these bends. In computer codes the air bubbles are assumed to behave like a surge tank with air which could dampen transient. This damping effect depends on the transient behaviour of the air bubbles. In this paper the transient behaviour of air bubbles at bends of long-distance pipelines is investigated by 1d and 3d numerical simulations and the results are compared with measurements performed at real systems.
Year: 2009