Hi all, I am currently working on a water pipeline project and am investigating a pipe burst scenario at a pump station with the aim of producing a flow rate entering the pump room in the event of a burst. For simplification and what has been used previously on similar jobs is to model the burst as an orrice of a certain size dependant on how large the mainline pipe is. Being a bi-directional pipeline, this pump station could experience either gravity flow dwon from a reservoir, or pumped flow from another pump station. My question has to do with modelling the head loss accross the orifice. The pipe under investigation is a DN600 ductile iron pipe, to be investigated with a DN250 orifice in a burst scenario. Previously the orifice as been modelled as a minor loss with a K factor of approximately 2.7. But I am questioning the accuracy of this as I cannot find reference to such a value. Can anyone provide any justifcation for this assumption. I will be happy to provide any additional information if needed.