Problem

How can I model a Vent Pipe or stand pipe in HAMMER?

Solution

The Surge Tank element is a good way of modeling a vent pipe or stand pipe in HAMMER, as it simulates water in a vertical pipe/tank with a free water surface.

If the lateral pipe connecting between the main pipeline and the main storage of the surge tank is not vertical, you can model it explicitly as pipes and junctions to account for the change in elevation/slope. Consider what the hydraulic impact of this connecting "standpipe" would be and how pressure waves would interact. If is stays pressurized, then it should act like a normal pressure pipe element would, in which case using pipes and junctions should be acceptable. If the pipe lengths are short, you may need a small calculation timestep as explained here. Or, consider a simplified approach with a single pipe that accounts for losses through the whole length - as long as negative or sub-atmospheric pressure is not a consider, modeling of the details of the slope of this pipe may not be necessary to simulate.

See below article for a note on what happens if the surge tank becomes empty during the transient simulation.

See Also

What happens when a tank becomes empty or full?

Modeling Reference - Surge Tanks