Rapid filling in pipe systems with column separation

A numerical exploration is used to identify three distinct sources which may give rise to column separation during rapid pipeline filling. Numerical experiments show that a knee point followed by a 'V'-shaped profile or a flow restriction, such as a partially closed valve, both may induce column separation. Moreover, this paper shows that pressure spikes arising from the two previous cases could themselves induce column separation in other parts of the system. Physical interpretations of the events captured by the model are provided to better understand this somewhat surprising phenomenon. The study shows that the complex course of events resulting in and from column separation are often quite non-intuitive, and that numerical studies are a necessary condition of even proposing an effective experimental study. © BHR Group 2012 Pressure Surges 11.