After running a water age analysis, the water age results from a hydropneumatic tank looks incorrect. The results indicate a water age older than the model run itself.Problem ID#: 73745
Hydropneumatic tanks are generally only used in transient analyses. While they can be used in WaterCAD as well, you will also likely need to use a small hydraulic time step (selected in the Steady State/EPS solver calculation options), since a hydropneumatic tank typically cycles relatively quickly. By using a smaller time step, the results should appear more accurate.
How are surge tanks and hydropneumatic tanks used in WaterGEMs and WaterCAD models?